Development of a Solid-Phase Extraction (SPE)...

Research ArticleDevelopment of a Solid-Phase Extraction (SPE) CartridgeBased on Chitosan-Metal Oxide Nanoparticles (Ch-MO NPs) forExtraction of Pesticides from Water andDetermination by HPLC

Mohamed E I Badawy Mahmoud A M El-Nouby and Abd El-SalamM Marei

Department of Pesticide Chemistry and Technology Faculty of Agriculture Alexandria University El-Shatby Alexandria 21545 Egypt

Correspondence should be addressed to Mohamed E I Badawy m eltaheryahoocom

Received 17 March 2018 Revised 31 July 2018 Accepted 2 September 2018 Published 2 October 2018

Academic Editor Valentina Venuti

Copyright copy 2018 Mohamed E I Badawy et al This is an open access article distributed under the Creative Commons AttributionLicense which permits unrestricted use distribution and reproduction in any medium provided the original work is properlycited

The present study aims to prepare two new types of chitosan-metal oxide nanoparticles (Ch-MO NPs) namely chitosan-copperoxide nanoparticles (Ch-CuONPs) and chitosan-zinc oxide nanoparticles (Ch-ZnO NPs) using sol-gel precipitation mechanismand test them new as adsorbent materials for extraction and clean-up of different pesticides from water The design of core-shell was implemented by metal oxide core with chitosan as a hard shell after crosslinking mechanism by glutaraldehyde andthen epichlorohydrin The characterizations of the prepared nanoparticles were investigated using Fourier transform infraredspectrometry (FT-IR) zeta potential scanning electron microscopy (SEM) transmission electron microscope (TEM) and X-raydiffraction (XRD) FT-IR confirmed the interaction between chitosan metal oxide and crosslinking mechanism SEM and TEMexplained that the nanoparticles have a spherical morphology and nanosize of 9374 and 9795 nm for Ch-CuO NPs and Ch-ZnONPs respectively Factorial experimental design was applied to study the effect of pH concentration of pesticide agitation timeand temperature on the efficiency of adsorption of pesticides from water samples The results indicated that optimum conditionswere pH of 7 temperature of 25∘C and agitation time of 25min The SPE cartridges were then packed with Ch-MO NPs andseven pesticides of abamectin diazinon fenamiphos imidacloprid lambda-cyhalothrin methomyl and thiophanate-methyl wereextracted from water samples and determined by HPLC The extraction efficiency of Ch-ZnO NPs was higher than Ch-CuO NPsbut both removed a larger amount of most of tested pesticides than the standard ODS cartridge (C18) The results showed that thismethod achieves rapid and simple extraction in small quantities of adsorbents (Ch-MONPs) and solvents In addition the methodis highly sensitive to pesticides and has a high recovery rate

1 Introduction

Pesticides are widely used in agricultural production toprevent or control pests diseases weeds and other plantpathogens in an effort to minimize or eliminate yield lossesand maintain high quality of products [1 2] Widespreaduses of pesticides with all groups such as organochlorinesorganophosphorus carbamates pyrethroids and neonicoti-noids have resulted in extensive contamination of wateratmosphere and soil as well as agricultural products whicheventually lead to food safety issues [3]Water contaminationwith pesticides is considered a serious problem and may

pose a risk to human health such as acute neurologicaltoxicity neurodevelopmental impairment cancer allergiesneurological disorders and reproductive disorders [2 4ndash6]

Different analytical techniques have been used for samplepreparation and clean-up with differentiation of sensitivityand selectivity [7] which include liquid-liquid extraction(LLE) [8] solid-phase extraction (SPE) [9] solid-phasemicroextraction (SPME) [10] dispersible solid-phase extrac-tion (d-SPE) headspace solid-phase extraction [11] and stirbar sorptive extraction (SBSE) [12] SPE was introduced inthe early 1970s to avoid and minimize the disadvantage ofLLE technique The SPE is a superior extraction and clean-up

HindawiInternational Journal of Analytical ChemistryVolume 2018 Article ID 3640691 16 pageshttpsdoiorg10115520183640691

2 International Journal of Analytical Chemistry

method that uses a solid phase and a liquid phase to sepa-rate the analyte from the sample without impurities beforeanalysis by dint of speed less usage of organic solvent lowcost and ability to obtain a higher preconcentration factor[13 14] Recently advanced materials for SPE extraction havebeen investigated with separation by liquid chromatographyand ultraviolet absorption detection (HPLCUV) [15ndash17]

Some of the most common sorbents in SPE are generallysimilar to those in column liquid chromatography such as theprimary secondary amine (PSA) octadecyl-siloxane (C18)graphitized carbon black (GCB) alumina and florisil PSA isnormally used in the d-SPE to remove interferences such asfree fatty acids sugars and other nonpolar compounds fromthe sample However the most commercial stationary phaseused in SPE is octadecyl-siloxane (C18) used in the reversedphase to extract the nonpolar compounds like pesticides[18 19]

Recently the biopolymer materials have been shown tobe of low cost and good efficiency in removal of various con-taminants from aqueous media Among these biopolymerschitosan (poly-120573-(1997888rarr4)-2-amino-2-deoxy-D-glucose) [2021] has been considered to be one of the most promisingand applicable materials in adsorption applications [22] Theexistence of the two functional groups of hydroxyl (-OH)and amino (-NH2) in its molecular structure contributes tomany possible adsorptions and gives highly powerful removalcapacity of dyes metal ions phenols pharmaceuticals drugsand other pollutants including the pesticides from environ-ment and wastewater [23]

Metal oxide particles have been used in many functions[24] in various polymeric materials to improve the per-manence of the polymeric products [25] In addition thenanoparticles of these products could increase the stiffnesstoughness and service life of polymeric materials [26] Thechitosan-metal oxide complexes in nanostructure form havebeen extensively modified to improve the adsorption capacityof chitosan molecule because of their limited size and a highdensity in their corner or edge surface sites [6] Dehaghiand coauthors synthesized the chitosan-ZnO nanoparticles(Ch-ZnO NPs) for adsorption applications in the removalof pesticide pollutants [25] They found that the 05 g of theCh-ZnO NPs in room temperature and pH 7 removed 99of permethrin insecticide solution (01mgL) Copper-coatedchitosan nanocomposite (Ch-Cu) was prepared and used foradsorption of parathion and methyl parathion insecticidein the batch mode The maximum adsorption capacity ofmalathion was found to be 3226mgg at an optimum pHof 20 The adsorbent was found to remove malathion com-pletely from the spiked concentration of 2mgL in one minin the agricultural run-off samples [24]

Chemical modification promotes crosslinking of thepolymer chains This process consists of joining polymerchains with the help of high reactivity chemicals calledcrosslinking agents generating polymer networksThismod-ification type is only possible by the presence of functionalgroups of high reactivity in the structure of these poly-mers Most notably glutaraldehyde and epichlorohydrin ascrosslinking agents considerably improve the mechanicalstrength the hardness of the chitosan particles and the

chemical stability in acidic media [27 28] Epichlorohydrinwas selected as a convenient base catalyzed crosslinkingagent An advantage of epichlorohydrin is that it does noteliminate the cationic amine function of chitosan but it reactswith hydroxyl groups in chitosan Glutaraldehyde has beenused more frequently since it is less expensive nontoxic andhighly soluble in aqueous solution It is a dialdehyde whosealdehydic groups are highly reactive and can form covalentbondswith functional groups such as primary amine by Schiffbase suggesting that the conjugated aldehyde moieties in thepolymers yield more stable reaction products [29ndash31]

In the current study new chitosan-metal oxide nanopar-ticles (Ch-MO NPs) including chitosan-CuO nanoparticles(Ch-CuO NPs) and chitosan-ZnO nanoparticles (Ch-ZnONPs) were prepared through the crosslinking mechanism byglutaraldehyde and then epichlorohydrin The nanoparticleswere used as a stationary phase in the preparation of SPE car-tridge The SPE cartridges were used in extraction and clean-up of pesticides from water samples The efficiency of theprepared cartridge of adsorption or retention of the differentpesticides including abamectin diazinon fenamiphos imi-dacloprid lambda-cyhalothrin methomyl and thiophanatemethyl was tested at three concentrations of each pesticideThe targeted pesticides are known to have been extensivelyused in agriculture in Egypt The pesticide residues weredetermined by HPLC system This protocol addresses thedetection of trace amounts of these pesticides in water andoptimizes the conditions for SPE technique compared withthe commercial SPE of Supelco Sigma product

2 Materials and Methods

21 Chemicals Low molecular weight of acid-soluble chi-tosan (360 times 105Da and 88 degree of deacetylation)glutaraldehyde (50) epichlorohydrin (99) toluene dim-ethylformamide and ethyl acetate were purchased fromSigma-Aldrich Co (St Louis Missouri USA) HPLC-gradeof acetonitrile methanol and water were purchased fromCarlo-Erba Reagents SAS Co (Chaussee du Vexin 27100Val-de-Reuil France) Zinc oxide (ZnO) red copper (I)oxide (Cu2O) acetic acid nitric acid and sodium hydroxidewere purchased from El-Gomhoria for pharmaceutical andchemicals Co (Adeb Ishak St Manshia Alexandria Egypt)and used without further purification

22 Technical Pesticides Technical grade of abamectin (96purity) was purchased from Merck and Co Inc (Kenil-worth New Jersey USA) Chlorpyrifos methyl (97) waspurchased from Dow Chemical Co (Midland MichiganUSA) Diazinon (90) was purchased from Syngenta Inter-national AG Co (Schwarzwaldallee 215 4002 Basel Switzer-land) Fenamiphos (90) was purchased from Miles IncCo (8400 Hawthorn Road Stilwell Kansas City USA)Imidacloprid (96) was purchased fromBayer AGCo (51368Leverkusen Germany) Lambda-cyhalothrin (97) was pur-chased from Syngenta International AG Co (Schwarzwal-dallee 215 4002 Basel Switzerland) Methomyl (98) waspurchased from EI du Pont de Nemours and Co (Wilming-ton Delaware 19805 USA) and thiophanate-methyl (94)

International Journal of Analytical Chemistry 3

was purchased from Pennwalt Ltd Co (D-221 MIDCTTC Industrial Area Thane Belapur Road Nerul NaviMumbai Maharashtra India) The chemical structures ofthese pesticides are shown in Figure S1

23 Instruments and Equipment High-Performance LiquidChromatography (HPLC) Agilent technology infinity 1260(Germany) equipped with an Agilent variable wavelengthultraviolet detector (VWD) was used The system consistsof a quaternary gradient solvent pump to control the flowrate of the mobile phase and an autosampler for automaticinjection with a 100120583L sample loop a vacuum degasserand a column oven (5-80∘C) Separation was performedon ZORBAX Eclipse Plus C18 analytical column (250 times46mm id 5 120583m particle size) Data were managed usingHP Chemstation software Perkin Elmer FT-IR Spectropho-tometer L160000A with detector LiTaO3 PerkinElmer Inc(Waltham Massachusetts USA) Malvern Zeta-Nano-sizerusing Laser Doppler Micro-Electrophoresis Malvern instru-ment Ltd Co (Enigma Business Park Grove wood RoadMalvern WR14 1XZ UK) UV-visible SpectrophotometerAlpha 1502 (Laxco Inc Bothell WA 98021 USA) scanningelectron microscope (SEM) JSM5300 JEOL Ltd (AkishimaTokyo Japan) transmission electron microscope (TEM)JEOL JEM-1400 (USA) Brukerrsquos X-ray diffraction (XRDUSA) ultrasonic homogenizer HD 2070 with HF generator(GM 2070) ultrasonic converter UW 2070 booster horn (SH213 G) and probe microtip MS 73 Oslash 3mm BANDELINelectronic GmbH amp Co (KG Heinrichstraszlige Berlin Ger-many) hotplate with magnetic stirrer IKA-Werke GmbH ampCo (Breisgau-Hochschwarzwald Germany) oven HeraeusCo (KG-Hanau Germany) and electric balances three andfour digits BL-410SLCD Setra systems Inc (59 Swanson RdBoxborough MA 01719 USA) were used

24 Preparation of Chitosan-Metal Oxide Nanoparticles (Ch-MO NPs) Ch-MO NPs including chitosan-copper oxide(Ch-CuO) and chitosan-zinc oxide (Ch-ZnO) nanoparticleswere prepared according to the method of Dehaghi andothers with minor modifications [25] A weight (4 g) ofchitosan was dissolved in 100mL aqueous acetic acid solution(1 vv) and stirred for 2 h using magnetic stirrer (solutionA) The desired amount of metal oxide (1mol metal ions per1mol amino group of chitosan) was added to the solutionIn the case of Ch-Cu complex Cu2O (709 g) was dissolvedin 20mL diluted nitric acid (2 vv) (solution B) howeverin the case of Ch-Zn complex ZnO (8 g) was dissolved in10mL concentrated nitric acid (solution C) Solution B or Cwas added dropwise to the solution A using a syringe undercontinuous stirring for 2 h until the metal ions conjugatedwith a chitosan polymer After that 12mL of glutaraldehyde(50 vv) as a first crosslinking agent was added dropwiseto the mixture under stirring followed by addition of 8mLepichlorohydrin (99) as a second crosslinking agent undercontinuous stirring The pHwas adjusted to 10 byNaOH (1N)dropwise by syringe under stirring The reaction mixture wasthen sonicated for 15min at a sonication power of 10 kHzand pulses or cycles (9 cycle sec) Finally the solution wasstored in a water bath at 60∘C for 3 h until precipitation The

precipitate was filtered washed with distilled water and driedat 70∘C for 3 h

25 Characterizations of Ch-MO NPs

251 Scanning Electron Microscope (SEM) The samples ofCh-MO NPs were investigated using a JEOL SEM with amagnification of 20000x and acceleration voltage of 19 kVThe dry particles were suspended in ethyl alcohol by soni-cation in dismantling the assembled particles After that theparticles were mounted on metal stubs with double-sidedtape sputtered with gold and viewed in an SEM

252 Transmission Electron Microscope (TEM) TEM obser-vation was performed on a JEOL JEM-1400 electron micro-scope (USA) at accelerating voltage of 120 kV Specimens forTEM measurements were prepared by depositing a drop ofcolloid solution on a 400mesh copper grid coated by anamorphous carbon film and evaporating the solvent in air atroom temperature

253 X-Ray Diffraction (XRD) X-ray diffractograms onpowder samples were obtained using a Brukerrsquos X-ray diffrac-tion (USA) with Cu tube radiation (k = 154184 A) a graphitemonochromator and Lynxeye detector at 30 kV and a currentof 10mAThediffractometerwas controlled and operated by aPC computer with the DIFFRACSUITE software packageMeasurements were taken over an angular range of 099∘ le2120579 le 8999∘ with a scanning step of 005 and a fixed countingtime of 10 s Divergence scattered and receiving radiationslits were 1∘ 1∘ and 02 mm respectively

254 Zeta Potential The surface charge of Ch-MO NPs wasinvestigated by a Malvern Zeta-Nano-sizer instrument Thefixed weight (01gm) of the prepared particles was suspendedin glycerol (50) in isopropanol (vv) and then they weresonicated for 30min The suspension was transferred to zetapotential cell [32]

255 FT-IR Spectroscopy The functional groups of Ch-MONPs was analyzed by FT-IR spectroscopy with KBr discs(5mg of Ch-MO NPs and 100mg KBr pellets) in the rangefrom 4000 to 400 cmminus1 with a resolution of 40 cmminus1 on aPerkin Elmer 1600 FT-IR Spectrophotometer (USA) [20]

26 Kinetic Study The preliminary study was conducted toinvestigate the influence of some factors (pH of the solutiontemperature and agitation time) on the adsorption efficiencyof imidacloprid (as a pesticide example) on Ch-CuO NPsusing full factorial design inMINITAB software v1710 2002(Minitab Inc Co Pine Hall Rd State College PA 16801-3008USA) The three factors were tested at three levels includinglow level high level and medium level coded as -1 +1 and 0respectivelyTheminimumnumber of experimental runs thathave to be carried out for two levels with three factors designis 23 = 8 runs plus 1 run at a center point The experimentswere carried out using 100mg of each type of nanoparticlessuspended in 25mL of imidacloprid solution (25mgL) at 1025 and 40∘C pH 5 7 and 9 and different agitation times


Filter

FilterAdsorbent

Syringe

9 Cm

Filters

Syringe

9 mm

Water

Pesticides

Adsorption

and elution

Addition oforganic solventElutionInjection into HPLC

(methanolacetonitrile)

Adsorbent025 g

Packing with 250 mg of Ch-MO NPs

Addition of filter on upper surface of the

adsorbentCartridge

compressed

40

30

20

10

0

minus10

1 2 3 4 5 6 Min

mAU

Figure 1 A schematic diagram shows extraction and clean-up of pesticides using SPE cartridge packed with Ch-MONPs (Ch-CuONPs andCh-ZnO NPs) This figure is reproduced from Badawy et al (2018) (under the Creative Commons Attribution Licensepublic domain)

(10 25 and 40min) with shaking at 150 rpm The blanksamples were added and placed in the same shaker to avoidloss of evaporation of pesticide or solvent After each timewith different experiments the eluent was determined byHPLC [2 25 33]

27 Solid-Phase Extraction (SPE) of Different Pesticides byCh-MO NPs The prepared nanoparticles were studied assolid matrix materials in SPE cartridge The SPE cartridgewas performed using a plastic syringe column of 09 cmdiameter and 9 cm in length (Figure 1) The column wasfilled up without gaps by compressing a frit on the bottomand then adding 025 g of each Ch-MO NPs and stopcockfrit on the upper [34] We compared these cartridges withthe ODS (C18 Supelco) cartridge as it is the most commonmaterial used in extraction and clean-up of pesticide residuesThree different concentrations (10 50 and 100mgL) ofeach pesticide (abamectin diazinon fenamiphos imida-cloprid lambda-cyhalothrin methomyl and thiophanate-methyl) were prepared by dissolving the tested pesticide ina minimum volume of methanol and then completed to thefinal volume of 20mL with water The prepared solutionswere allowed to pass through the SPE cartridge After thatthe adsorbed amount of each pesticide was eluted by 5mL ofacetonitrilemethanol (11 vv)

28 HPLC Analysis The water phase (effluent) and organicphase (eluent) were collected from SPE cartridge and injectedinto HPLC The summary of the optimum conditions forchromatographic analysis of each pesticides is presented inTable S1 For analysis calibration five standard solutions ofeach pesticide were prepared by dissolving weighed amount

in the mobile phase used for each pesticide and differentquantities (00125-015120583gmL) were injected into HPLC Cal-ibration curves were constructed by plotting the peak areasof compound against the amount injected in 120583g Regressionanalysis of the data (n = 5) for each calibration curve gavethe values of slope along with the intercept and correlationcoefficient Calibration curves were used for the quantifica-tion of the pesticides in water samples The limit of detection(LOD) and limit of quantification (LOQ) for each pesticidewere calculated The LOD is the lowest concentration of theanalyte in a sample that can still be detected by the analyticalmethod but should not be quantified as an appropriatevalue However the LOQ is the lowest concentration ofthe sample that can still be quantitatively detected withacceptable precision and accuracy [35] LOD was defined as3120590S and LOQ was defined as 10120590S where 120590 is the standarddeviation and S is the slope of the calibration curve [36]

29 Statistical Analysis The statistical analysis was per-formed using the SPSS 250 software (Statistical Package forSocial Sciences USA) Analysis of variance (ANOVA) ofthe data was conducted and means property values wereseparated by Student-Newman-Keuls (SNK) test Differenceswere considered significant at p le 005The statistical analysisof adsorption kinetics was investigated by full factorial designusing a MINITAB software v1710 2002 (Minitab Inc CoPine Hall Rd State College PA 16801-3008 USA)

3 Results and Discussion

31 Preparation of Ch-MO NPs The Ch-MO NPs were syn-thesized through combining the sol-gel precipitation and


Table 1 Reaction conditions and characterizations of chitosan-metal oxide nanoparticles (Ch-MO NPs)

Product code Reaction components Mole ratio Productcolor Yield () Particles diameter (nm)

plusmn SEZeta-potential

(mV)

Ch-CuO NPs Chitosan Cu2O Glutaraldehyde 1223 Yellowish-dark 8529 9374plusmn570 +0516

Epichlorohydrin

Ch-ZnO NPs Chitosan ZnO Glutaraldehyde 1423 Yellowish 9167 9795plusmn946 +0086Epichlorohydrin

crosslinking mechanism [27] as illustrated in Figure S2Monodispersedmetal oxide particles were coated by chitosanas the uniform of core or shell layer They were then sequen-tially crosslinked with glutaraldehyde and epichlorohydrinFirstly glutaraldehyde forms the hard-spherical shape ofparticles through reaction with the amino groups of chitosanIn the second stage the epichlorohydrin reacted with thehydroxyl groups to give more hardness for particles andreduce the hydrophilicity of chitosan The final product wasprecipitated by aqueous solution of NaOH (1N) The yieldswere 8529 and 9167 for Ch-CuO NPs and Ch-ZnONPs respectively with a yellowish and dark yellowish colorrespectively (Table 1)

Many research articles prepared and characterized pol-ymer-supported metals and metal oxide nanoparticlesincluding chitosan-ZnO and chitosan-CuO and some ofwhich suggested the previous mechanism of the particleformation [26 37] For example Shrifian-Esfahni et alprepared and characterized Fe3O4chitosan core-shell andthe mechanism investigated hydrogen-bonding formationIn addition the authors indicated the unbonded hydroxylgroups with partial positive charges surrounding nanopar-ticle [37] Therefore we completed this reaction in our studyby crosslinking agent to cover the reactive functional groups(amino and hydroxyl) Recently we prepared chitosan-siloxane magnetic nanoparticles from Fe3O4 functionalizedby siloxane derivatives followed by coating with chitosanthrough a crosslinking mechanism using glutaraldehyde andepichlorohydrin [34]


321 Scanning Electron Microscope (SEM) The SEM wasused to investigate the surface morphology and particle sizeof Ch-CuO NPs and Ch-ZnO NPs as shown in Figures 2(a)and 2(b) respectively The particles in nanocomposites werefound with almost spherical morphology with aggregationsof the nanoparticles Nanoparticles were measured with anaverage size of 9374 and 9795 nm for Ch-CuO NPs andCh-ZnO NPs respectively (Table 1) Dehaghi and coauthorsprepared Ch-ZnO NPs without crosslinking reaction andthey found that the particles size was in a arrange of 58 nm[25] HoweverManikanndan and others prepared the Ch-Cucomplex without crosslinking reactions with an average sizeranging from 20 to 30 nm [38] Gouda and Hebeish loadedCuO NPs into chitosan by using drops of H2O2 (30) andthen stirring with a high-speed homogenizer at 10000 rpmfor 30minThe corresponding CuOchitosan nanocomposite

formed was characterized by using transmission electronmicroscope (TEM) images and they presented a very homo-geneous morphology with a quite uniform particle sizedistribution and a rather spherical shape [39] The particlesize diameters obtained were 10 nm for chitosan nanoparticleand 20 nm for CuOchitosan nanocomposite

322 Transmission Electron Microscope (TEM) TEM pho-tographs of Ch-CuO NPs and Ch-ZnO NPs are presentedin Figures 2(c) and 2(d) respectively It is evident that theparticles are formed with average sizes ranging from 75to 100 nm In addition the nanoparticles of both productsshowed high agglomeration of smaller size nanoparticles andtheir surface was rough and porous because metal oxideparticles were wrapped by chitosan matrix

323 X-Ray PowderDiffraction (XRD) TheX-ray diffractionpatterns of Ch-MO NPs are shown in Figure 3 Figure 3(a)shows the characteristic peaks at 2120579 sim 10∘ and 2120579 sim20∘ due to inter- and intramolecular hydrogen bonds inchitosan molecule [40 41] However these two peaks arevery weak in the spectra of Ch-CuO NPs and Ch-ZnONPs (Figures 3(b) and 3(c) respectively) which suggest alow crystallinity and an amorphous nature of the productsThe weak peaks reflect great disarray in chain alignment ofchitosan with the production of new peaks identifying zincoxide and copper oxideTheX-ray diffraction patterns of Ch-CuO NPs (Figure 3(b)) demonstrated diffraction angles of2358∘ 2608∘ 2998∘3367∘3987∘ 5335∘ and 7780∘ whichcorrespond to the characteristic face centered CuO core withcounts index (260) (415) (240) (458) (255) (149) and(110) respectively [42 43] The diffraction angles observedat 1086∘ and 2034∘ corresponding to count indexes (134)and (250) respectively refer to the chitosan shell The mainpeaks of Ch-ZnO NPs (Figure 3(c)) were at 2120579 = 3091∘3355∘ 3542∘ 4671∘ 5580∘ 6208∘ 6722∘ and 6828∘ whichcorrespond to the (1159) (1023) (1563) (391) (566) (449)(411) and (258) crystal planes respectively These peaks areconsistent with the database in Joint Committee on PowderDiffraction Standards for ZnO (JCPDS file PDFNo 36-1451)[44] In addition two smaller peaks at 2120579 = 7631∘ and 8884∘corresponding to the count (157) and (170) respectivelywere also observed The diffraction angles observed at 1098∘and 2076∘ corresponding to count indexes (211) and (289)respectively refer to the chitosan shell

324 Zeta Potential Zeta potential is the surface chargevalue and it is a key indicator of the stability of colloidal


(a)

(a)

(b)

(b)

(c)

(c)

(d)

(d)

Figure 2 Electron microscopy images of Ch-MO NPs (a) (b) The SEM of Ch-CuO NPs and Ch-ZnO NPs respectively (c) (d) The TEMof Ch-CuONPs and Ch-ZnO NPs respectively Scale bar for SEM measurements was 1 120583m and magnification x20000 at 20 Kv Scale bar forTEM measurements was 100 nm and magnification x40000 at 20 Kv

dispersionsThemagnitude of the zeta potential indicates thedegree of electrostatic repulsion between charged particlesin a dispersion For molecules and particles that are smallenough a high zeta potential will confer stability ie thesolution or dispersion will resist aggregation [32 45] In thepresent study the values were +0516mV for Ch-CuO NPsand +0086mV for Ch-ZnO NPs (Table 1 and Figure S3)indicating a rapid coagulation or flocculation of particlesin suspension at pH 7 and 25∘C It can be noted that thenanoparticles of Ch-CuO NPs have a higher charge (asymp 5-fold) than Ch-ZnO NPsThe positive charge of zeta potentialvalues obtained refers to the surface charge of the particlesThe previous study reported that the Ch-Cu complex has anegative charge (-29 mv) [38] However the Ch-Zn complexhad a positive charge (+266) [46] The low surface chargeof the prepared nanoparticles (Ch-CuO and Ch-ZnO) maybe due to the crosslinking reaction that blocked the hydroxyland amino functional groups The glutaraldehyde blocks theamino groups of chitosan while the hydroxyl groups wereblocked by epichlorohydrin [29 47 48]

325 FT-IR The FT-IR spectra of chitosan and Ch-MONPsare shown in Figure 4The spectrumof pure chitosan exhibitsbands at 3436 cmminus1 due to the stretching vibration mode

of ndashOH and -NH2 groups The peak at 2924 cmminus1 is a typeof C-H stretching vibration while the band at 1655 cmminus1 isdue to the amide I group (C-O stretching along with N-H deformation mode) A band at 1590 cmminus1 is attributedto the NH2 group due to N-H deformation while a bandat 1419 cmminus1 is due to C-N axial deformation (amine groupband) In addition the peak at 1380 cmminus1 peak is due tothe COOminus group in carboxylic acid salt and the band at1160 cmminus1 is assigned to the special broad peak of 120573 (1ndash4)glucosidic bond in polysaccharide unit However the peak at1080 cmminus1 is attributed to the stretching vibrationmode of thehydroxyl group 989-1060 cmminus1 stretching vibrations of C-O-C in glucose units [20]

The FT-IR spectrum of Ch-ZnO NPs exhibits band at3401 cmminus1 due to the combination between -OH and -NH2groups The peak at 2932 cmminus1 is a typical of C-H stretchvibration The band at 1657 cmminus1 is due to the rest of amideI group while a band at 1553 cmminus1 is attributed to the NH2group due to N-H deformation The peak at 1407 cmminus1 is dueto C-N axial deformation (amine group band) In additionthe band at 1067 cmminus1 is attributed to the stretching vibrationmode of the hydroxyl group and the band at 682 cmminus1ascribed to the vibration of O-Zn-O core groups


300

280

260

240

220

200

180

160

140

120

100

80

60

40

20

Inte

nsity

1000 2000 3000 4000 5000 6000 7000 8000 9000

Position (2)

(a)

Inte

nsity

1000 2000 3000 4000 5000 6000 7000 8000 9000

Position (2)

500

450

400

350

300

250

200

150

100

50

(b)

1000 2000 3000 4000 5000 6000 7000 8000 9000

Inte

nsity

Position (2)

1600

1500

1400

1300

1200

1100

1000

900

800

700

600

500

400

300

200

100

(c)

Figure 3 X-ray diffraction (XRD) patterns of chitosan (a) Ch-CuONPs (b) and Ch-ZnO NPs (c)

The spectrum of Ch-CuO NPs exhibits bands at3390 cmminus1 due to the combination between -OH and-NH2 groups The peak at 2924 cmminus1 indicates a C-Hstretching vibration A band at 1583 cmminus1 is attributed to theNH2 group due to N-H deformation and 1410 cmminus1 peakis due to C-N axial deformation (amine group band) A

band at 1380 cmminus1 is due to the COO- group in carboxylicacid salt while the peak at 1070 cmminus1 is attributed to thestretching vibration mode of the hydroxyl group The bandat 682 cmminus1 is attributed to the vibration of O-Cu-O coregroups However the peak at 493 is ascribed to Cu-O bondvibration


Table 2 Experimental design usingMinitab software and standardized effects of temperature pH and time on the adsorption of imidaclopridinsecticide at 25mgL on Ch-CuONPs

Run order Temperature (∘C) pH Time (min) Adsorption () plusmn SE1 10 5 10 1218plusmn0582 40 5 10 3186plusmn1163 10 9 10 6221plusmn0624 40 9 10 8424plusmn0785 10 5 40 1923plusmn1776 40 5 40 2793plusmn2017 10 9 40 9291plusmn1728 40 9 40 10000plusmn0009 25 7 25 8743plusmn098

Chitosan

Ch-CuO NPs

Ch-ZnO NPs

3436

3390

3401

2924

2882

1553

15831410

1407

1067

1070

682

4000 500100020003000

Tran

smitt

ance

()

5855

50

45

40

35

30

25

20

15

10

5

493

1419

2932

2877

16551590 1160

1380

1060

989

10801657

Wavenumber cm-

Figure 4 FT-IR spectra of chitosan (A) chitosan-copper oxidenanoparticles (Ch-CuO NPs) and chitosan-zinc oxide nanoparti-cles (Ch-ZnO NPs)

In comparison with chitosan the broader and strongerpeak shifted considerably to lower wave number at 3390 cmminus1in Ch-CuO NPs and 3401 cmminus1 in Ch-ZnO NPs whichindicates strong attachment of metal oxide to the amidegroups of chitosan molecules (Figure 4) The absorptionpeaks at 2877-2924 in Ch-MO NPs are due to asymmetricstretching of CH2 and CH3 of chitosan polymer and theoverlapping with -NH The absorption peaks at 1583 and1070 cmminus1 in the spectrum of Ch-CuO NPs are attributed tobending vibration of the -NH group and the C-O stretchinggroup but these peaks were observed at 1553 and 1067 cmminus1in spectrum of Ch-ZnO NPs New broad absorption bandsat 682 and 400 cmminus1 were found in the FT-IR spectra of Ch-MONPswhich were ascribed to the vibration of O-Cu-O andO-Zn-O groups [49 50]

33 Kinetic Studies of Adsorption Efficiency of Pesticides byCh-MO NPs Three factors (pH temperature and agitationtime) were studied on the efficiency of Ch-CuO NPs in theadsorption of imidacloprid insecticide at 25mgL The fullfactorial design was used in terms of the experimental runsand the experimental data are shown in Table 2 The resultsindicate that the pH values of 7 and 9 showed the mostsignificant effect on the adsorption efficiency of imidaclopridwith 6221 8424 9291 100 and 8743 for run 3 4 7 8 and

Term

C

A

B

A TemperatureB pHC Time

Factor Name

2571

Pareto Chart of the Standardized Effects(response is Adsorption () = 005)

1 2 3 4 5 60Standardized Effect

Figure 5 Pareto Chart of the standardized effects of pH tempera-ture and time of adsorption (response is adsorption () 120572 = 005)

9 respectively To investigate the main effect of all factorsthe adsorption efficiency was studied using the Pareto chartand the result is shown in Figure 5 The most affecting factoris the pH followed by temperature and then agitation timeThe Pareto chart provides a clear visualization of the factoreffects and indicates that the pHhas themost significant effecton the adsorption at 120572 = 005 however the temperature andagitation time did not show values lower than the referenceline (2571 at 120572 = 005) [2 25] From this analysis theadsorption () can be calculated or predicted according tothe following model (1)

Adsorption () = minus733 + 0479 Temperature

+ 1551 pH + 0413 Time

S = 1628 and

R2 = 8640

(1)

It can be noted that the three factors have a positive signthat means that the adsorption will be increased with anincrease in each factor The factor has a greater correlationfactor denoting the great effects Therefore the pH has agreat effect (coefficient = 1551) on the adsorption followedin the descending order by temperature (coefficient = 0479)


Table 3 Statistical data from regression analysis of different pesticides obtained from the study with analytical HPLC methods

Pesticide Rt (min) plusmn SD As plusmn SD Regression equation R2 LOD (120583gmL) LOQ (120583gmL)Abamectin 7999 plusmn 001 0871 plusmn 000 y = 452345190x-270225 09998 0023 0077Diazinon 7975 plusmn 000 0870 plusmn 001 y = 117760010x+042100 09999 0046 0154Fenamiphos 3374 plusmn 001 0885 plusmn 001 y = 321411453x+089949 09997 0002 0006Imidacloprid 3647 plusmn 000 0853 plusmn 004 y = 472825710x+0794634 09998 0020 0066Lambda-cyhalothrin 10761 plusmn 005 0923 plusmn 005 y = 287416095x+0431849 09999 0012 0040Methomyl 2795 plusmn 003 0953 plusmn 000 y = 497213330x+361685 09997 0018 0059Thiophanate-methyl 4566 plusmn 001 1070 plusmn 000 y = 341234475x+1124269 09997 0024 0081

Rt retention time As peak asymmetry factor R2 linear correlation coefficient LOD limit of detection LOQ limit of quantification

and then the agitation time (coefficient = 0413) In additionthree-dimensional response surface plots are presented inFigure S4 These plots provide useful information about thebehavior of the systemwithin the experimental design whichwas used to understand the main and interactive effects ofthe factors The effect of pH temperature and agitation timeon pesticides adsorption percentage was shown at initialconcentration in Figure S4 rightThe results indicated that theadsorption or retention percentage increased with increasingof the pH and temperature but the optimum adsorptionpercentage was observed at pH 7 and temperature of 25∘CThese results are consistent with the previous study whichreported that the removal rate of pyrethrin increased by anincrease of pH to 8 [25] The adsorption ratio increasedat pH increase and induction time from 10 to 40min butthe optimal adsorption was performed at pH 7 and after25 minutes However the effect of time and temperaturehas proved the previous theory that confirmed that optimaltemperature and induction time are from 25∘C to 40∘C and25 to 40 minutes respectively at the top of the surface plotcurve The contour plots shown in Figure S4 indicate theinteraction between the pH and temperature and confirmedthat the optimum adsorption was found at pH ranging from65 to 9 with the optimal temperature from 25 to 40∘C

34 SPE of Pesticides Using Ch-MO NPs and HPLC AnalysisHPLC analytical methods for the tested pesticides werevalidated by calculating regression equation correlation coef-ficient (R2) peak asymmetry factor (As) LOD and LOQfor each pesticide and the data are presented in Table 3The values of R2 obtained for the regression lines demon-strate the excellent relationship between peak area and theinjected amount of all pesticides (R2 ge 0999) The LODof the pesticides determined by HPLC ranged from 0002to 0046 120583gmL and the LOQ was in the range of 0006 to0154120583gmL The asymmetry factor (As) is an indication forthe peak tailing [51 52] being in the range of 0870 to 1070

The efficacy data of Ch-MO NPs (250mg) in extractionand removal of pesticides from water samples at threelevels (10 50 and 100mgL) is presented in Tables 4 and5 for Ch-CuO NPs and Ch-ZnO NPs respectively andcompared to the standard ODS cartridge (Supelco) (Table 6)The data are presented as a percentage of that extractedby methanol acetonitrile (5050) and that found in waterphase It can be noted that the removal percentages were

decreased with the increase of the concentration Table 4shows the results of cartridge loaded with Ch-CuO NPsAll pesticides were adsorbed into the Ch-CuO NPs withhigh percentages compared to the amount remaining in thewater phase Lambda-cyhalothrin was the highest in removal(9893 9519 and 9266 at 10 50 and 100mgL respectively)followed in the descending order by abamectin (9802 9434and 9231 at 10 50 and 100mgL respectively) Howeverthere is no significant difference between both insecticidesFenamiphos showed 9533 9328 and 9044 and thenimidacloprid with 9378 9039 and 7291 at 10 50 and100mgL respectively However methomyl and thiophanate-methyl showed moderate values (6385-8475) Diazinonwas the lowest pesticide among all the tested pesticides inremoval percentages (7015 3421 and 2144 at 10 50 and100mgL respectively) Ch-CuO NPs demonstrated that noamount of lambda-cyhalothrin was found in water at any ofthe tested concentrations This finding may be due to thefact that the lambda-cyhalothrin has a very low solubilityin water and a highest octanol-water partition coefficientvalue compared to the other tested pesticides [53] followed inthe descending order by imidacloprid thiophanate-methylfenamiphos and abamectin However methomyl indicatedhigh percentages in water (2055 2500 and 3337 at 10 50and 100mgL respectively) This is may be due to the highsolubility of this compound in the water [54]

All pesticides were also adsorbed into the Ch-ZnONPs with high percentage compared to that found in thewater phase and lambda-cyhalothrin was the highest inremoval with 9909 9800 9447 at 10 50 and 100mgLrespectively (Table 5) followed in the descending order byabamectin fenamiphos and imidacloprid However diazi-non and thiophanate-methyl showedmoderate values (6010-9428) Methomyl was the lowest pesticide among all testedpesticides (4140 3851 and 3662 at 10 50 and 100mgLrespectively) These particles proved that the insecticidelambda-cyhalothrin was not detected in water at any ofthe tested concentrations However methomyl showed highpercentages in water (1809 5782 and 6259 at 10 50 and100mgL respectively)

Table 6 shows the recovery of pesticides at 10 50 and100mgL from water using the standard SPE cartridge(C18) obtained from Supelco Diazinon fenamiphos andthiophanate-methyl were the most pesticides extracted fromthis type of cartridge in all tested concentrations However


Table4Effi

ciency

ofCh

-CuO

NPs

inadsorptio

nof

different

pesticidesu

singsolid

phasee

xtractioncartrid

getechniqu

e

Pest

icid

esRe

mov

al(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

ent(

)f

ound

inw

aterplusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9802aplusmn341

9474

aplusmn102

9231

aplusmn023

000

fplusmn000

253

eplusmn047

394

eplusmn009

9802aplusmn455

9727aplusmn135

9625aplusmn013

Diazino

n7015

bplusmn146

3421eplusmn110

2144fplusmn025

1889bplusmn106

1905bplusmn103

2381bplusmn060

8904aplusmn201

5327cplusmn198

4525cplusmn072

Fenamipho

s9533

aplusmn169

9328a

bplusmn099

9044aplusmn104

403

dplusmn018

467

dplusmn015

731dplusmn009

9936aplusmn159

9794aplusmn063

9776

aplusmn032

Imidacloprid

9378aplusmn045

9039

bplusmn061

7291dplusmn030

580

cplusmn028

816

cplusmn009

2596bplusmn096

9958aplusmn022

9975aplusmn049

9887aplusmn058

Lambd

a-cyhalothrin

9844aplusmn101

9514

aplusmn041

9266aplusmn007

000

fplusmn000

000

fplusmn000

000

fplusmn000

9844aplusmn058

9514

aplusmn014

9266bplusmn002

Metho

myl

7715

bplusmn028

7017

dplusmn000

6385eplusmn039

2055aplusmn027

2500aplusmn065

3337

aplusmn234

9770aplusmn048

9516

aplusmn057

9722aplusmn079

Thioph

anate-methyl

8475bplusmn182

7891cplusmn089

7462cplusmn022

514

eplusmn011

819

cplusmn004

2247cplusmn010

8989aplusmn092

8710

bplusmn086

9709aplusmn016

lowastTh

evalues

lowe

rthan

100

meantheno

nextracted

amou

ntof

pesticide

from

Ch-C

uONPsV

aluesa

remeanof

threereplicates

andaregivenas

meanplusmnsta

ndarderrorDifferentletters

inthesamecolumn

indicatesig

nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)


Table5Effi

ciency

ofCh

-ZnO

NPs

inadsorptio

nof

different

pesticidesu

singsolid

phasee

xtractioncartrid

getechniqu

e

Pest

icid

esRe

mov

al(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

ent(

)f

ound

inw

aterplusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9872aplusmn531

9315

aplusmn065

9263aplusmn066

000

eplusmn000

184eplusmn018

251

eplusmn006

9872aplusmn405

9499bplusmn026

9515

bplusmn057

Diazino

n9428bplusmn153

7612

bplusmn114

7255cplusmn122

525

bplusmn047

1808bplusmn025

2301bplusmn036

9954aplusmn172

9415

bplusmn042

9556bplusmn089

Fenamipho

s9521bplusmn353

9333

aplusmn092

8720bplusmn044

434

cplusmn036

442

dplusmn013

752d

eplusmn004

9955aplusmn279

9775a

bplusmn068

9472bplusmn040

Imidacloprid

9690a

bplusmn035

9776

aplusmn068

8847bplusmn061

169dplusmn016

221

eplusmn016

1042c

dplusmn007

9958aplusmn022

9997aplusmn076

9888aplusmn027

Lambd

a-cyhalothrin

9909aplusmn078

9800aplusmn161

9447cplusmn041

000

eplusmn000

000

fplusmn000

000

fplusmn000

9909aplusmn055

9800a

bplusmn100

9447bplusmn020

Metho

myl

4147dplusmn108

3851cplusmn031

3662fplusmn056

1809aplusmn027

5782aplusmn025

6259aplusmn033

5956bplusmn118

9633

abplusmn009

9921aplusmn078

Thioph

anate-methyl

9062cplusmn086

6060bplusmn052

6010

eplusmn022

349

cplusmn004

666

cplusmn014

1234cplusmn007

9411

aplusmn0886726cplusmn038

7244cplusmn018

lowastTh

evalues

lowe

rthan

100

meantheno

nextracted

amou

ntof

pesticide

from

Ch-ZnO

NPsV

aluesaremeanof

threereplicates

andaregivenas

meanplusmnsta


inthesamecolumn

indicatesig

nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)


Table6Effi

ciency

ofsta

ndardODScartrid

ge(Sup

elco)inadsorptio

nof

different

pesticidesu

singSP

Etechniqu

e

Pest

icid

esRe

mov

aleffi

cien

cy(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

entf

ound

inw

ater

()plusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9759aplusmn251

954

a 4plusmn048

4811

cplusmn017

0000eplusmn00

428

eplusmn043

1186

dplusmn065

9759aplusmn251

9972aplusmn045

5997cplusmn034

Diazino

n9936aplusmn205

9628aplusmn043

8765aplusmn028

0000eplusmn000

200

fplusmn004

745eplusmn067

9936aplusmn205

9832

aplusmn042

9510

aplusmn047

Fenamipho

s8420bplusmn304

7828bplusmn046

7860bplusmn041

1445aplusmn065

1654bplusmn029

1696cplusmn025

9865aplusmn184

9482aplusmn056

9556aplusmn045

Imidacloprid

8016

bplusmn103

5126cplusmn045

3120dplusmn119

811plusmnd 011

1390cplusmn014

3684aplusmn023

8827aplusmn098

6516

cplusmn034

6804bplusmn071

Lambd

a-cyhalothrin

9388aplusmn121

7205bplusmn246

51709

cplusmn055

0000eplusmn00

742dplusmn034

1064dplusmn065

9388aplusmn121

7947bplusmn149

6243bplusmn060

Metho

myl

4037

dplusmn063

2820dplusmn046

2335dplusmn108

1187

cplusmn087

1399cplusmn087

2298bplusmn098

5224bplusmn076

4219

dplusmn063

4633

dplusmn096

Thioph

anate-methyl7898cplusmn426

7530bplusmn040

7428bplusmn022

1307bplusmn000

1965aplusmn065

2467bplusmn083

9205aplusmn426

9495aplusmn053

9895aplusmn052

lowastTh

evalueslow

erthan

100

meanthen

onextractedam

ount

ofpesticide

from

stand

ardsolid

phasee

xtractioncartrid

geV

aluesa

remeanofthreer

eplicatesandareg

iven

asmeanplusmnsta


inthes

amecolumnindicatesig

nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)


Table 7 Enrichment factor (EF) of Ch-Si MNPs for adsorption of different pesticides from water sample

PesticidesEF plusmn SE of Ch-MO NPs at three levels of pesticide concentrations (120583gmL)

10 50 100 Mean plusmn SE 10 50 100 Mean plusmn SE 10 50 100 Mean plusmn SECh-CuO NPs Ch-ZnO NPs ODS (Supelco)

Abamectin 822 947 851 873a plusmn 031 828 931 854 871a plusmn 026 819 958 443 740a plusmn 126Diazinon 524 274 175 324b plusmn 085 704 610 593 636ab plusmn 028 742 771 717 743a plusmn 013Fenamiphos 756 735 724 738a plusmn 008 755 735 698 729ab plusmn 014 668 616 628 637b plusmn 013Imidacloprid 739 760 512 670ab plusmn 065 764 822 622 736ab plusmn 049 632 459 219 437c plusmn 098Lambda-cyhalothrin 787 1080 731 866a plusmn 089 793 1113 745 883a plusmn 095 737 818 408 654b plusmn 103Methomyl 934 564 431 643ab plusmn 124 502 310 247 353c plusmn 063 489 227 158 291d plusmn 083Thiophanate-methyl 676 632 597 635ab019 723 485 481 563bc plusmn 066 630 603 594 609b plusmn 009Values are mean of three replicates and are given as mean plusmn standard error Different letters in the same column indicate significant differences according toStudent-Newman-Keuls (SNK) test (Ple005)

methomyl is still less compared to others It can be observedthat the standard SPE cartridge (C18) showed a disparity inextraction efficiency and was the least cartridge comparedwith Ch-CuO NPs and Ch-ZnO NPs in the recovery ofmost tested pesticides including abamectin (recovery of4811-9759) fenamiphos (recovery of 7860-8420) imi-dacloprid (recovery of 3120-8016) lambda-cyhalothrin(recovery of 5170-9388) andmethomyl (recovery of 2335-4037) Unfortunately the SPE has certain limitationsprimarily related to low recovery ie slightly lower sensi-tivity in cases where the SPE column is blocked (blockingthe absorption centers by the samplersquos solid and organiccomponents) [55]

The enrichment factor (EF) of the prepared and standardcartridges is shown in Table 7 EF can be defined as theconcentration of the analyte in organic phase to the originalconcentration in the aqueous phase The results showed thatthe EF of Ch-CuO NPs ranged from 324 for diazinon to873 for abamectin However there is no significant differenceamong the other pesticides The EF of Ch-ZnO NPs rangedfrom 353 formethomyl to 883 for lambda-cyhalothrin It canbe noted that the EF values of the prepared cartridges werehigher than the standard ODS (C18) which had a range of291-743

SPE became one of the most widely used treatmentmethods for various samples [56 57] This technology hasmany advantages including high enrichment factor easyoperation high recovery rapid phase separation low costlow consumption of organic solvents and effective matrixinterference [58] In the SPE process the synthesis of adsor-bents is the fundamental issue since the type and amount ofabsorbance largely determine selectivity sensitivity and fullrecovery In general propertieswith large surface areas activesurface locations and a short propagation path can providea significant number of improvements in extraction kinetics[59] Compared with conventional adsorbents nanoscalemetal oxides have attracted more interest from researchersin recent years given their high surface area and rapidabsorption kinetics Several results confirmed that the Ch-MO NPs were high adsorbent materials and used in SPEtechnique for extraction and removal of different pollutants[24 25] Ch-Zn was prepared and applied for removal

of permethrin at optimum conditions including adsorbentdose agitating time the initial concentration of pesticideand pH on the adsorption [25] The results indicated thatthe weight of 05 g of the bionanocomposite at room tem-perature and pH 7 removed 99 of permethrin solution(25mL 01mg L) using UV spectrophotometer at 272 nmCopper-coated chitosan nanocomposite (Ch-Cu) was foundto have high adsorption efficiency for parathion and methylparathion and maximum adsorption capacity of parathionwas found to be 32260mgg at an optimum pH of 20 [24]This could be attributed to the inherent alkalinity of theadsorbent In addition high adsorption value of malathioncould be explained by acidic hydrolysis of malathion todithiophosphate followed by complexation of copper to formCu (II) dithiophosphate Ch-AgO NPs composite beads werealso optimized to remove maximum permethrin as themodel pesticide with the amount of sorbent agitating timeinitial concentration of pesticide and pH parameters [2]In optimum conditions room temperature and pH 7 theCh-AgO NPs beads recovered 99 of permethrin solution(010mgL) using UV spectrophotometer compared to 50with the pure chitosan

35 Adsorption Isotherm Study Adsorption isothermmodelsare important to determine the efficiency of the adsorp-tion process Adsorption isotherms illustrate the connectionbetween the amount of adsorbed component per adsorbentweight and the concentration of the contaminated com-ponents in the solution Determination of the adsorptionparameters provides useful information which can improvethe adsorption efficiency of the systems In the present studythe adsorption percentages were applied in Freundlich (1)and Langmuir (3) isotherm models as follows to predictwhich model is fit

q = KfC1n (2)

q = qmaxKlC1 + KlC

(3)

where q is adsorption capacity (120583gg) Kf is Freundlichisotherm constant (120583gg) C is concentration of the analyte


(adsorbate) in the solution at equilibrium (120583gmL) n isadsorption intensity qmax is maximum adsorption mono-layer capacity (120583gg) and Kl is Langmuir isotherm constant(mL120583g)

By analyzing the linear correlation coefficient (R2) ob-tained it is possible to identify the isotherm model thatbest represents the experimental data of this study [60]From the values of R2 obtained (Table S2) for the Ch-MONPs it is possible to conclude that both of Langmuir andFreundlich isotherms are fit to this study with R2 gt 092When the experimental data follows the Langmuir modelthis assumes that a monomolecular layer is formed whenadsorption takes place without any interaction between theadsorbed molecules However the data follows the Fre-undlich isotherm which means that the adsorption processtakes place on heterogeneous surfaces and adsorption capac-ity is related to the concentration of the analyte at equilibrium[61] The maximum adsorption capacity (qmax) of Ch-MONPs was observed for all the tested pesticides The Ch-CuO NPs and Ch-ZnO NPs showed the highest adsorptioncapacities (250 times 104 and 100 times 105 120583gg respectively) forthiophanate-methyl compared to 100 times 104 120583gg by usingODS (C18) However the insecticide methomyl showed a low119902max on Ch-CuO NPs and Ch-ZnO NPs (200 times 103 100 times103 120583gg respectively) compared to 286 times 102 by using ODS(C18)

4 Conclusion

Novel Ch-MONPs stationary phases for SPE technique wereprepared and characterized by FT-IR SEM TEM XRD andZeta-Nano-sizer The chromatographic retention behaviorsof seven pesticides on Ch-MO NPs were investigated andcompared with standard ODS (C18 column) The factors ofthe pH temperature and agitation time were studied on theefficiency of these products in adsorption or retention ofimidacloprid insecticide and the results proved that the pHwas the most significant factor It was reported that the Ch-MO NPs are able to remove the selected pesticides at theoptimum condition of agitation time 25min pH 7 and 25∘CCh-CuO NPs and Ch-ZnO NPs exhibited high selectivityfor the tested pesticides as solutes and the extracted amountby these products was more than the ODS in most casesat three levels of concentrations (10 50 and 100mgL inaqueous solution) The new adsorbent nanoparticles behavedas a reversed phase retentionmechanism based on hydropho-bic interaction as well as inclusion interactions and weakhydrophilicity for the polar pesticides such as methomylbased on partitioning and surface adsorption process Thenanoparticles will possess great prospect in chromatographicanalysis especially SPE and SPME techniques In additionthese products are newly biocompatible environmentallyfriendly and low cost to extract and clean-up pesticides fromwastewater In future this work will be conducted on thepacking of the HPLC columns with these products as newalternatives to the current stationary phases for separation ofpesticide residues

Data Availability

All data generated or analyzed during this study are includedin this article In addition the related datasets are availablefrom the corresponding author on reasonable request

Conflicts of Interest

The authors confirm that they have no conflicts of interestregarding the publication of this article

Supplementary Materials

Figure S1 shows the chemical structures of tested pesticides(abamectin chlorpyrifos methyl diazinon fenamiphos imi-dacloprid lambda-cyhalothrin methomyl and thiophanate-methyl) Figure S2 shows the 3D-schematic diagram forpreparation mechanism of Ch-MO NPs Figure S3 shows thezeta potential distribution graph of Ch-MO NPs Figure S4presents the surface plot and contour plot of the adsorption() of imidacloprid insecticide on Ch-CuO NPs versus tem-perature pH and agitation time Table S1 shows a summaryof the methods conditions used for determination of differentpesticides byHPLC system Table S2 indicates the parametersof the isothermal models of Ch-MO NPs for adsorption ofdifferent pesticides (Supplementary Materials)

References

[1] F Ahmadi Y Assadi S M R M Hosseini and M RezaeeldquoDetermination of organophosphorus pesticides in water sam-ples by single drop microextraction and gas chromatography-flame photometric detectorrdquo Journal of Chromatography A vol1101 no 1-2 pp 307ndash312 2006

[2] B Rahmanifar and S Moradi Dehaghi ldquoRemoval of organ-ochlorine pesticides by chitosan loaded with silver oxide na-noparticles from waterrdquo Clean Technologies and EnvironmentalPolicy vol 16 no 8 pp 1781ndash1786 2014

[3] K L Howdeshell A K Hotchkiss and L E Gray ldquoCumulativeeffects of antiandrogenic chemical mixtures and their relevanceto human health risk assessmentrdquo International Journal ofHygiene and Environmental Health vol 220 no 2 pp 179ndash1882017

[4] K-H Kim E Kabir and S A Jahan ldquoExposure to pesticidesand the associated human health effectsrdquo Science of the TotalEnvironment vol 575 pp 525ndash535 2017

[5] A M Cimino A L Boyles K A Thayer and M J PerryldquoEffects of neonicotinoid pesticide exposure on human healthA systematic reviewrdquo Environmental Health Perspectives vol125 no 2 pp 155ndash162 2017

[6] K Yoshizuka Z Lou and K Inoue ldquoSilver-complexed chitosanmicroparticles for pesticide removalrdquo Reactive and FunctionalPolymers vol 44 no 1 pp 47ndash54 2000

[7] S D Zaugg MW Sandstrom S G Smith and K M FehlbergldquoMethods of analysis by the US Geological Survey NationalWater Quality Laboratory determination of pesticides in waterby C-18 solid-phase extraction and capillary-column gas chro-matographymass spectrometry with selected-ionmonitoringrdquoUS Geological Survey Open-File Reports SectionESIC 1995


[8] D A J Murray ldquoRapid micro extraction procedure for analysesof trace amounts of organic compounds in water by gas choro-matography and comparisons with macro extraction methodsrdquoJournal of Chromatography A vol 177 no 1 pp 135ndash140 1979

[9] I Liska J Krupcıik and P A Leclercq ldquoThe use of solidsorbents for direct accumulation of organic compounds fromwater matricesndasha review of solid-phase extraction techniquesrdquoJournal of High Resolution Chromatography vol 12 no 9 pp577ndash590 1989

[10] M T Muldoon and L H Stanker ldquoMolecularly imprinted solidphase extraction of atrazine from beef liver extractsrdquoAnalyticalChemistry vol 69 no 5 pp 803ndash808 1997

[11] S M Yousefi F Shemirani and S A Ghorbanian ldquoDeepeutectic solvent magnetic bucky gels in developing dispersivesolid phase extraction Application for ultra trace analysis oforganochlorine pesticides by GC-micro ECD using a large-volume injection techniquerdquo Talanta vol 168 pp 73ndash81 2017

[12] T AAlbanis D G Hela TM Sakellarides and I K Konstanti-nou ldquoMonitoring of pesticide residues and their metabolitesin surface and underground waters of Imathia (N Greece) bymeans of solid-phase extraction disks and gas chromatographyrdquoJournal of Chromatography A vol 823 no 1-2 pp 59ndash71 1998

[13] T F Jenkins P HMiyares K FMyers E FMcCormick andAB Strong ldquoComparison of solid phase extraction with salting-out solvent extraction for preconcentration of nitroaromaticand nitramine explosives from waterrdquo Analytica Chimica Actavol 289 no 1 pp 69ndash78 1994

[14] G-M Momplaisir C G Rosal E M Heithmar et al ldquoDevel-opment of a solid phase extraction method for agriculturalpesticides in large-volume water samplesrdquo Talanta vol 81 no4-5 pp 1380ndash1386 2010

[15] Y S Al-Degs M A Al-Ghouti and A H El-Sheikh ldquoSimulta-neous determination of pesticides at trace levels in water usingmultiwalled carbon nanotubes as solid-phase extractant andmultivariate calibrationrdquo Journal of Hazardous Materials vol169 no 1-3 pp 128ndash135 2009

[16] L Vidal M-L Riekkola and A Canals ldquoIonic liquid-modifiedmaterials for solid-phase extraction and separation a reviewrdquoAnalytica Chimica Acta vol 715 pp 19ndash41 2012

[17] L Costa dos Reis L Vidal and A Canals ldquoGraphene oxideFe3O4 as sorbent for magnetic solid-phase extraction coupledwith liquid chromatography to determine 246-trinitrotoluenein water samplesrdquo Analytical and Bioanalytical Chemistry vol409 no 10 pp 2665ndash2674 2017

[18] A Zwir-Ferenc and M Biziuk ldquoSolid phase extraction tech-nique - Trends opportunities and applicationsrdquo Polish Journalof Environmental Studies vol 15 no 5 pp 677ndash690 2006

[19] J Pawliszyn Solid phase microextraction theory and practiceJohn Wiley Sons 1997

[20] M E Badawy E I Rabea N E Taktak and M A El NoubyldquoProduction and Properties of Different Molecular Weights ofChitosan from Marine Shrimp Shellsrdquo Journal of Chitin andChitosan Science vol 4 no 1 pp 46ndash54 2016

[21] E I Rabea M E-T Badawy C V Stevens G Smagghe andWSteurbaut ldquoChitosan as antimicrobial agent applications andmode of actionrdquoBiomacromolecules vol 4 no 6 pp 1457ndash14652003

[22] A Domard and M Domard ldquoChitosan structure-propertiesrelationship and biomedical applicationsrdquo Polymeric Biomate-rials vol 2 pp 187ndash212 2001

[23] M Masuelli and D Renard Advances in Physicochemical Prop-erties of Biopolymers (Part 2) BENTHAMSCIENCEPUBLISH-ERS 2017

[24] M Jaiswal D Chauhan andN Sankararamakrishnan ldquoCopperchitosan nanocomposite Synthesis characterization and appli-cation in removal of organophosphorous pesticide from agri-cultural runoffrdquo Environmental Science and Pollution Researchvol 19 no 6 pp 2055ndash2062 2012

[25] S Moradi Dehaghi B Rahmanifar A M Moradi and P AAzar ldquoRemoval of permethrin pesticide fromwater by chitosan-zinc oxide nanoparticles composite as an adsorbentrdquo Journal ofSaudi Chemical Society vol 18 no 4 pp 348ndash355 2014

[26] S Sarkar EGuibal FQuignard andAK SenGupta ldquoPolymer-supported metals and metal oxide nanoparticles synthesischaracterization and applicationsrdquo Journal of NanoparticleResearch vol 14 no 2 article 715 2012

[27] M E I BadawyN EM TaktakOMAwad S A Elfiki andNE A El-Ela ldquoPreparation and Characterization of BiopolymersChitosanAlginateGelatin Gel Spheres Crosslinked by Glu-taraldehyderdquo Journal of Macromolecular Science Part B Physicsvol 56 no 6 pp 359ndash372 2017

[28] C Tual E Espuche M Escoubes and A Domard ldquoTransportproperties of chitosan membranes Influence of crosslinkingrdquoJournal of Polymer Science Part B Polymer Physics vol 38 no11 pp 1521ndash1529 2000

[29] W-W Xiong W-F Wang L Zhao Q Song and L-MYuan ldquoChiral separation of (RS)-2-phenyl-1-propanol throughglutaraldehyde-crosslinked chitosan membranesrdquo Journal ofMembrane Science vol 328 no 1-2 pp 268ndash272 2009

[30] M Gabriel Paulraj S Ignacimuthu M R Gandhi et al ldquoCom-parative studies of tripolyphosphate and glutaraldehyde cross-linked chitosan-botanical pesticide nanoparticles and theiragricultural applicationsrdquo International Journal of BiologicalMacromolecules vol 104 pp 1813ndash1819 2017

[31] W Tong C Gao and H Mohwald ldquoManipulating the proper-ties of polyelectrolyte microcapsules by glutaraldehyde cross-linkingrdquo Chemistry of Materials vol 17 no 18 pp 4610ndash46162005

[32] SHonary andF Zahir ldquoEffect of zeta potential on the propertiesof nano-drug delivery systemsmdasha review (part 1)rdquo TropicalJournal of Pharmaceutical Research vol 12 no 2 pp 255ndash2642013

[33] J L D O Arias C Rombaldi S S Caldas and E G PrimelldquoAlternative sorbents for the dispersive solid-phase extractionstep in quick easy cheap effective rugged and safe methodfor extraction of pesticides from rice paddy soils with determi-nation by liquid chromatography tandem mass spectrometryrdquoJournal of Chromatography A vol 1360 pp 66ndash75 2014

[34] M E Badawy A E Marei and M A El-Nouby ldquoPreparationand characterization of chitosan-siloxane magnetic nanoparti-cles for the extraction of pesticides from water and determina-tion byHPLCrdquo Separation Science Plus vol 1 no 7 pp 506ndash5192018

[35] USDepartment of Health and Human Services (FDA)Analyti-cal Procedures And Methods Validation Chemistry Manufactur-ing And Controls Documentation vol 65 2000

[36] A Teasdale D Elder and R W Nims ICH Quality GuidelinesJohn Wiley amp Sons Inc Hoboken NJ USA 2017

[37] A Shrifian-Esfahni M T Salehi M Nasr-Esfahni and EEkramian ldquoChitosan-modified superparamgnetic iron oxidenanoparticles Design fabrication characterization andantibacterial activityrdquo Chemik vol 69 no 1 pp 19ndash32 2015


[38] A M Muthukrishnan ldquoGreen synthesis of copper-chitosannanoparticles and study of its antibacterial activityrdquo Journal ofNanomedicine amp Nanotechnology vol 6 no 1 2015

[39] M Gouda and A Hebeish ldquoPreparation and evaluation ofCuOchitosan nanocomposite for antibacterial finishing cottonfabricrdquo Journal of Industrial Textiles vol 39 no 3 pp 203ndash2142010

[40] K L Haas and K J Franz ldquoApplication of metal coordinationchemistry to explore and manipulate cell biologyrdquo ChemicalReviews vol 109 no 10 pp 4921ndash4960 2009

[41] F S Pereira S Lanfredi E R P Gonzalez D L da Silva Agos-tini H M Gomes and R dos Santos Medeiros ldquoThermal andmorphological study of chitosan metal complexesrdquo Journal of13ermal Analysis and Calorimetry vol 129 no 1 pp 291ndash3012017

[42] M S Usman N A Ibrahim K Shameli N Zainuddin andW M Z W Yunus ldquoCopper nanoparticles mediated by chi-tosan synthesis and characterization via chemical methodsrdquoMolecules vol 17 no 12 pp 14928ndash14936 2012

[43] P Senthil Kumar M Selvakumar S Ganesh Babu S Indujaand S Karuthapandian ldquoCuOZnO nanorods An affordableefficient p-n heterojunction and morphology dependent pho-tocatalytic activity against organic contaminantsrdquo Journal ofAlloys and Compounds vol 701 pp 562ndash573 2017

[44] L-H Li J-C Deng H-R Deng Z-L Liu and L Xin ldquoSyn-thesis and characterization of chitosanZnO nanoparticle com-posite membranesrdquo Carbohydrate Research vol 345 no 8 pp994ndash998 2010

[45] S Patil A Sandberg E Heckert W Self and S Seal ldquoProteinadsorption and cellular uptake of cerium oxide nanoparticlesas a function of zeta potentialrdquo Biomaterials vol 28 no 31 pp4600ndash4607 2007

[46] A Regiel-FutyraM Kus-Liskiewicz SWojtyła G Stochel andW Macyk ldquoThe quenching effect of chitosan crosslinking onZnO nanoparticles photocatalytic activityrdquo RSC Advances vol5 no 97 pp 80089ndash80097 2015

[47] Y Gao K-H Lee M Oshima and S Motomizu ldquoAdsorp-tion behavior of metal ions on cross-linked chitosan and thedetermination of oxoanions after pretreatment with a chitosancolumnrdquoAnalytical Sciences vol 16 no 12 pp 1303ndash1308 2000

[48] I A Udoetok R M Dimmick L D Wilson and J V Head-ley ldquoAdsorption properties of cross-linked cellulose-epichloro-hydrin polymers in aqueous solutionrdquo Carbohydrate Polymersvol 136 pp 329ndash340 2016

[49] A Bagabas A Alshammari M F A Aboud and H KosslickldquoRoom-temperature synthesis of zinc oxide nanoparticles indifferent media and their application in cyanide photodegrada-tionrdquo Nanoscale Research Letters vol 8 no 1 pp 1ndash10 2013

[50] S Basumallick and S Santra ldquoChitosan coated copper-oxidenano particles A novel electro-catalyst for CO2 reductionrdquoRSCAdvances vol 4 no 109 pp 63685ndash63690 2014

[51] Z Papai and T L Pap ldquoDetermination of chromatographicpeak parameters by non-linear curve fitting using statisticalmomentsrdquo Analyst vol 127 no 4 pp 494ndash498 2002

[52] G I K Marei E I Rabea andM E Badawy ldquoPreparation andCharacterizations of ChitosanCitral Nanoemulsions and theirAntimicrobial Activityrdquo Applied Food Biotechnology vol 5 pp69ndash78 2018

[53] J Liu X Lu J Xie Y Chu C Sun and QWang ldquoAdsorption oflambda-cyhalothrin and cypermethrin on two typical Chinesesoils as affected by copperrdquo Environmental Science and PollutionResearch vol 16 no 4 pp 414ndash422 2009

[54] R I Krieger P Brutsche-KeiperHRCrosby andADKriegerldquoReduction of pesticide residues of fruit using water only orplus Fit Fruit and Vegetable Washrdquo Bulletin of EnvironmentalContamination and Toxicology vol 70 no 2 pp 213ndash218 2003

[55] R Đurovic and T Đordevic Modern extraction techniquesfor pesticide residues determination in plant and soil samplesPesticides in the Modern World-Trends in Pesticides AnalysisInTech 2011

[56] Ł Rajski A Lozano A Ucles C Ferrer and A R Fernandez-Alba ldquoDetermination of pesticide residues in high oil vegetalcommodities by using various multi-residue methods andclean-ups followed by liquid chromatography tandem massspectrometryrdquo Journal of Chromatography A vol 1304 pp 109ndash120 2013

[57] D Molins-Delgado D Garcıa-Sillero M S Dıaz-Cruz andD Barcelo ldquoOn-line solid phase extraction-liquid chromatog-raphy-tandem mass spectrometry for insect repellent residueanalysis in surfacewaters using atmospheric pressure photoion-izationrdquo Journal of Chromatography A vol 1544 pp 33ndash402018

[58] Z Li J Li Y Wang and Y Wei ldquoSynthesis and applicationof surface-imprinted activated carbon sorbent for solid-phaseextraction and determination of copper (II)rdquo SpectrochimicaActa Part A Molecular and Biomolecular Spectroscopy vol 117pp 422ndash427 2014

[59] R Khorasani K Dindarloo Inaloo M Heidari M Behbahaniand O Rahmanian ldquoApplication of solvent-assisted dispersivesolid phase extraction combined with flame atomic absorptionspectroscopy for the determination of trace amounts of Cad-miumrdquoHormozgan Medical Journal vol 20 no 6 pp 383ndash3922017

[60] P M Silva J E Francisco J C Caje R J Cassella and W FPacheco ldquoA batch and fixed bed column study for fluoresceinremoval using chitosan modified by epichlorohydrinrdquo Journalof Environmental Science and Health Part A ToxicHazardousSubstances and Environmental Engineering vol 53 no 1 pp 55ndash64 2017

[61] F Naseeruteen N S A Hamid F B M Suah W S WNgah and F S Mehamod ldquoAdsorption of malachite green fromaqueous solution by using novel chitosan ionic liquid beadsrdquoInternational Journal of Biological Macromolecules vol 107 pp1270ndash1277 2018

TribologyAdvances in

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Chemistry


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Analytical Methods in Chemistry

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Volume 2018

Bioinorganic Chemistry and ApplicationsHindawiwwwhindawicom Volume 2018

SpectroscopyInternational Journal of


Hindawi Publishing Corporation httpwwwhindawicom Volume 2013Hindawiwwwhindawicom

The Scientific World Journal

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Medicinal ChemistryInternational Journal of


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Applied ChemistryJournal of



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SpectroscopyAnalytical ChemistryInternational Journal of


MaterialsJournal of



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International Journal of


Na

nom

ate

ria

ls


Journal ofNanomaterials

Submit your manuscripts atwwwhindawicom


method that uses a solid phase and a liquid phase to sepa-rate the analyte from the sample without impurities beforeanalysis by dint of speed less usage of organic solvent lowcost and ability to obtain a higher preconcentration factor[13 14] Recently advanced materials for SPE extraction havebeen investigated with separation by liquid chromatographyand ultraviolet absorption detection (HPLCUV) [15ndash17]

Some of the most common sorbents in SPE are generallysimilar to those in column liquid chromatography such as theprimary secondary amine (PSA) octadecyl-siloxane (C18)graphitized carbon black (GCB) alumina and florisil PSA isnormally used in the d-SPE to remove interferences such asfree fatty acids sugars and other nonpolar compounds fromthe sample However the most commercial stationary phaseused in SPE is octadecyl-siloxane (C18) used in the reversedphase to extract the nonpolar compounds like pesticides[18 19]

Recently the biopolymer materials have been shown tobe of low cost and good efficiency in removal of various con-taminants from aqueous media Among these biopolymerschitosan (poly-120573-(1997888rarr4)-2-amino-2-deoxy-D-glucose) [2021] has been considered to be one of the most promisingand applicable materials in adsorption applications [22] Theexistence of the two functional groups of hydroxyl (-OH)and amino (-NH2) in its molecular structure contributes tomany possible adsorptions and gives highly powerful removalcapacity of dyes metal ions phenols pharmaceuticals drugsand other pollutants including the pesticides from environ-ment and wastewater [23]

Metal oxide particles have been used in many functions[24] in various polymeric materials to improve the per-manence of the polymeric products [25] In addition thenanoparticles of these products could increase the stiffnesstoughness and service life of polymeric materials [26] Thechitosan-metal oxide complexes in nanostructure form havebeen extensively modified to improve the adsorption capacityof chitosan molecule because of their limited size and a highdensity in their corner or edge surface sites [6] Dehaghiand coauthors synthesized the chitosan-ZnO nanoparticles(Ch-ZnO NPs) for adsorption applications in the removalof pesticide pollutants [25] They found that the 05 g of theCh-ZnO NPs in room temperature and pH 7 removed 99of permethrin insecticide solution (01mgL) Copper-coatedchitosan nanocomposite (Ch-Cu) was prepared and used foradsorption of parathion and methyl parathion insecticidein the batch mode The maximum adsorption capacity ofmalathion was found to be 3226mgg at an optimum pHof 20 The adsorbent was found to remove malathion com-pletely from the spiked concentration of 2mgL in one minin the agricultural run-off samples [24]

Chemical modification promotes crosslinking of thepolymer chains This process consists of joining polymerchains with the help of high reactivity chemicals calledcrosslinking agents generating polymer networksThismod-ification type is only possible by the presence of functionalgroups of high reactivity in the structure of these poly-mers Most notably glutaraldehyde and epichlorohydrin ascrosslinking agents considerably improve the mechanicalstrength the hardness of the chitosan particles and the

chemical stability in acidic media [27 28] Epichlorohydrinwas selected as a convenient base catalyzed crosslinkingagent An advantage of epichlorohydrin is that it does noteliminate the cationic amine function of chitosan but it reactswith hydroxyl groups in chitosan Glutaraldehyde has beenused more frequently since it is less expensive nontoxic andhighly soluble in aqueous solution It is a dialdehyde whosealdehydic groups are highly reactive and can form covalentbondswith functional groups such as primary amine by Schiffbase suggesting that the conjugated aldehyde moieties in thepolymers yield more stable reaction products [29ndash31]

In the current study new chitosan-metal oxide nanopar-ticles (Ch-MO NPs) including chitosan-CuO nanoparticles(Ch-CuO NPs) and chitosan-ZnO nanoparticles (Ch-ZnONPs) were prepared through the crosslinking mechanism byglutaraldehyde and then epichlorohydrin The nanoparticleswere used as a stationary phase in the preparation of SPE car-tridge The SPE cartridges were used in extraction and clean-up of pesticides from water samples The efficiency of theprepared cartridge of adsorption or retention of the differentpesticides including abamectin diazinon fenamiphos imi-dacloprid lambda-cyhalothrin methomyl and thiophanatemethyl was tested at three concentrations of each pesticideThe targeted pesticides are known to have been extensivelyused in agriculture in Egypt The pesticide residues weredetermined by HPLC system This protocol addresses thedetection of trace amounts of these pesticides in water andoptimizes the conditions for SPE technique compared withthe commercial SPE of Supelco Sigma product

2 Materials and Methods

21 Chemicals Low molecular weight of acid-soluble chi-tosan (360 times 105Da and 88 degree of deacetylation)glutaraldehyde (50) epichlorohydrin (99) toluene dim-ethylformamide and ethyl acetate were purchased fromSigma-Aldrich Co (St Louis Missouri USA) HPLC-gradeof acetonitrile methanol and water were purchased fromCarlo-Erba Reagents SAS Co (Chaussee du Vexin 27100Val-de-Reuil France) Zinc oxide (ZnO) red copper (I)oxide (Cu2O) acetic acid nitric acid and sodium hydroxidewere purchased from El-Gomhoria for pharmaceutical andchemicals Co (Adeb Ishak St Manshia Alexandria Egypt)and used without further purification

22 Technical Pesticides Technical grade of abamectin (96purity) was purchased from Merck and Co Inc (Kenil-worth New Jersey USA) Chlorpyrifos methyl (97) waspurchased from Dow Chemical Co (Midland MichiganUSA) Diazinon (90) was purchased from Syngenta Inter-national AG Co (Schwarzwaldallee 215 4002 Basel Switzer-land) Fenamiphos (90) was purchased from Miles IncCo (8400 Hawthorn Road Stilwell Kansas City USA)Imidacloprid (96) was purchased fromBayer AGCo (51368Leverkusen Germany) Lambda-cyhalothrin (97) was pur-chased from Syngenta International AG Co (Schwarzwal-dallee 215 4002 Basel Switzerland) Methomyl (98) waspurchased from EI du Pont de Nemours and Co (Wilming-ton Delaware 19805 USA) and thiophanate-methyl (94)














Filter

FilterAdsorbent

Syringe

9 Cm

Filters

Syringe

9 mm

Water

Pesticides

Adsorption

and elution



Adsorbent025 g



adsorbentCartridge

compressed

40

30

20

10

0

minus10

1 2 3 4 5 6 Min

mAU













(mV)


Epichlorohydrin











(a)

(a)

(b)

(b)

(c)

(c)

(d)

(d)







300

280

260

240

220

200

180

160

140

120

100

80

60

40

20

Inte

nsity

1000 2000 3000 4000 5000 6000 7000 8000 9000

Position (2)

(a)

Inte

nsity

1000 2000 3000 4000 5000 6000 7000 8000 9000

Position (2)

500

450

400

350

300

250

200

150

100

50

(b)

1000 2000 3000 4000 5000 6000 7000 8000 9000

Inte

nsity

Position (2)

1600

1500

1400

1300

1200

1100

1000

900

800

700

600

500

400

300

200

100

(c)







Chitosan

Ch-CuO NPs

Ch-ZnO NPs

3436

3390

3401

2924

2882

1553

15831410

1407

1067

1070

682

4000 500100020003000

Tran

smitt

ance

()

5855

50

45

40

35

30

25

20

15

10

5

493

1419

2932

2877

16551590 1160

1380

1060

989

10801657

Wavenumber cm-




Term

C

A

B


Factor Name

2571






+ 1551 pH + 0413 Time

S = 1628 and

R2 = 8640

(1)













Table4Effi

ciency

ofCh

-CuO

NPs

inadsorptio

nof

different

pesticidesu

singsolid

phasee

xtractioncartrid

getechniqu

e

Pest

icid

esRe

mov

al(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

ent(

)f

ound

inw

aterplusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9802aplusmn341

9474

aplusmn102

9231

aplusmn023

000

fplusmn000

253

eplusmn047

394

eplusmn009

9802aplusmn455

9727aplusmn135

9625aplusmn013

Diazino

n7015

bplusmn146

3421eplusmn110

2144fplusmn025

1889bplusmn106

1905bplusmn103

2381bplusmn060

8904aplusmn201

5327cplusmn198

4525cplusmn072

Fenamipho

s9533

aplusmn169

9328a

bplusmn099

9044aplusmn104

403

dplusmn018

467

dplusmn015

731dplusmn009

9936aplusmn159

9794aplusmn063

9776

aplusmn032

Imidacloprid

9378aplusmn045

9039

bplusmn061

7291dplusmn030

580

cplusmn028

816

cplusmn009

2596bplusmn096

9958aplusmn022

9975aplusmn049

9887aplusmn058

Lambd

a-cyhalothrin

9844aplusmn101

9514

aplusmn041

9266aplusmn007

000

fplusmn000

000

fplusmn000

000

fplusmn000

9844aplusmn058

9514

aplusmn014

9266bplusmn002

Metho

myl

7715

bplusmn028

7017

dplusmn000

6385eplusmn039

2055aplusmn027

2500aplusmn065

3337

aplusmn234

9770aplusmn048

9516

aplusmn057

9722aplusmn079

Thioph

anate-methyl

8475bplusmn182

7891cplusmn089

7462cplusmn022

514

eplusmn011

819

cplusmn004

2247cplusmn010

8989aplusmn092

8710

bplusmn086

9709aplusmn016

lowastTh

evalues

lowe

rthan

100

meantheno

nextracted

amou

ntof

pesticide

from

Ch-C

uONPsV

aluesa

remeanof

threereplicates

andaregivenas

meanplusmnsta


inthesamecolumn

indicatesig

nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)


Table5Effi

ciency

ofCh

-ZnO

NPs

inadsorptio

nof

different

pesticidesu

singsolid

phasee

xtractioncartrid

getechniqu

e

Pest

icid

esRe

mov

al(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

ent(

)f

ound

inw

aterplusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9872aplusmn531

9315

aplusmn065

9263aplusmn066

000

eplusmn000

184eplusmn018

251

eplusmn006

9872aplusmn405

9499bplusmn026

9515

bplusmn057

Diazino

n9428bplusmn153

7612

bplusmn114

7255cplusmn122

525

bplusmn047

1808bplusmn025

2301bplusmn036

9954aplusmn172

9415

bplusmn042

9556bplusmn089

Fenamipho

s9521bplusmn353

9333

aplusmn092

8720bplusmn044

434

cplusmn036

442

dplusmn013

752d

eplusmn004

9955aplusmn279

9775a

bplusmn068

9472bplusmn040

Imidacloprid

9690a

bplusmn035

9776

aplusmn068

8847bplusmn061

169dplusmn016

221

eplusmn016

1042c

dplusmn007

9958aplusmn022

9997aplusmn076

9888aplusmn027

Lambd

a-cyhalothrin

9909aplusmn078

9800aplusmn161

9447cplusmn041

000

eplusmn000

000

fplusmn000

000

fplusmn000

9909aplusmn055

9800a

bplusmn100

9447bplusmn020

Metho

myl

4147dplusmn108

3851cplusmn031

3662fplusmn056

1809aplusmn027

5782aplusmn025

6259aplusmn033

5956bplusmn118

9633

abplusmn009

9921aplusmn078

Thioph

anate-methyl

9062cplusmn086

6060bplusmn052

6010

eplusmn022

349

cplusmn004

666

cplusmn014

1234cplusmn007

9411


7244cplusmn018

lowastTh

evalues

lowe

rthan

100

meantheno

nextracted

amou

ntof

pesticide

from

Ch-ZnO

NPsV

aluesaremeanof

threereplicates

andaregivenas

meanplusmnsta


inthesamecolumn

indicatesig

nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)


Table6Effi

ciency

ofsta

ndardODScartrid

ge(Sup

elco)inadsorptio

nof

different

pesticidesu

singSP

Etechniqu

e

Pest

icid

esRe

mov

aleffi

cien

cy(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

entf

ound

inw

ater

()plusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9759aplusmn251

954

a 4plusmn048

4811

cplusmn017

0000eplusmn00

428

eplusmn043

1186

dplusmn065

9759aplusmn251

9972aplusmn045

5997cplusmn034

Diazino

n9936aplusmn205

9628aplusmn043

8765aplusmn028

0000eplusmn000

200

fplusmn004

745eplusmn067

9936aplusmn205

9832

aplusmn042

9510

aplusmn047

Fenamipho

s8420bplusmn304

7828bplusmn046

7860bplusmn041

1445aplusmn065

1654bplusmn029

1696cplusmn025

9865aplusmn184

9482aplusmn056

9556aplusmn045

Imidacloprid

8016

bplusmn103

5126cplusmn045

3120dplusmn119

811plusmnd 011

1390cplusmn014

3684aplusmn023

8827aplusmn098

6516

cplusmn034

6804bplusmn071

Lambd

a-cyhalothrin

9388aplusmn121

7205bplusmn246

51709

cplusmn055

0000eplusmn00

742dplusmn034

1064dplusmn065

9388aplusmn121

7947bplusmn149

6243bplusmn060

Metho

myl

4037

dplusmn063

2820dplusmn046

2335dplusmn108

1187

cplusmn087

1399cplusmn087

2298bplusmn098

5224bplusmn076

4219

dplusmn063

4633

dplusmn096

Thioph


7530bplusmn040

7428bplusmn022

1307bplusmn000

1965aplusmn065

2467bplusmn083

9205aplusmn426

9495aplusmn053

9895aplusmn052

lowastTh

evalueslow

erthan

100

meanthen

onextractedam

ount

ofpesticide

from

stand

ardsolid

phasee

xtractioncartrid

geV

aluesa

remeanofthreer

eplicatesandareg

iven

asmeanplusmnsta


inthes


nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)











q = KfC1n (2)

q = qmaxKlC1 + KlC

(3)





4 Conclusion


Data Availability






References





































































Journal of

Chemistry





Journal of

Volume 2018






Volume 2018




Journal of






Enzyme Research


Journal of



MaterialsJournal of






Na

nom

ate

ria

ls

















Filter

FilterAdsorbent

Syringe

9 Cm

Filters

Syringe

9 mm

Water

Pesticides

Adsorption

and elution



Adsorbent025 g



adsorbentCartridge

compressed

40

30

20

10

0

minus10

1 2 3 4 5 6 Min

mAU













(mV)


Epichlorohydrin











(a)

(a)

(b)

(b)

(c)

(c)

(d)

(d)







300

280

260

240

220

200

180

160

140

120

100

80

60

40

20

Inte

nsity

1000 2000 3000 4000 5000 6000 7000 8000 9000

Position (2)

(a)

Inte

nsity

1000 2000 3000 4000 5000 6000 7000 8000 9000

Position (2)

500

450

400

350

300

250

200

150

100

50

(b)

1000 2000 3000 4000 5000 6000 7000 8000 9000

Inte

nsity

Position (2)

1600

1500

1400

1300

1200

1100

1000

900

800

700

600

500

400

300

200

100

(c)







Chitosan

Ch-CuO NPs

Ch-ZnO NPs

3436

3390

3401

2924

2882

1553

15831410

1407

1067

1070

682

4000 500100020003000

Tran

smitt

ance

()

5855

50

45

40

35

30

25

20

15

10

5

493

1419

2932

2877

16551590 1160

1380

1060

989

10801657

Wavenumber cm-




Term

C

A

B


Factor Name

2571






+ 1551 pH + 0413 Time

S = 1628 and

R2 = 8640

(1)













Table4Effi

ciency

ofCh

-CuO

NPs

inadsorptio

nof

different

pesticidesu

singsolid

phasee

xtractioncartrid

getechniqu

e

Pest

icid

esRe

mov

al(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

ent(

)f

ound

inw

aterplusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9802aplusmn341

9474

aplusmn102

9231

aplusmn023

000

fplusmn000

253

eplusmn047

394

eplusmn009

9802aplusmn455

9727aplusmn135

9625aplusmn013

Diazino

n7015

bplusmn146

3421eplusmn110

2144fplusmn025

1889bplusmn106

1905bplusmn103

2381bplusmn060

8904aplusmn201

5327cplusmn198

4525cplusmn072

Fenamipho

s9533

aplusmn169

9328a

bplusmn099

9044aplusmn104

403

dplusmn018

467

dplusmn015

731dplusmn009

9936aplusmn159

9794aplusmn063

9776

aplusmn032

Imidacloprid

9378aplusmn045

9039

bplusmn061

7291dplusmn030

580

cplusmn028

816

cplusmn009

2596bplusmn096

9958aplusmn022

9975aplusmn049

9887aplusmn058

Lambd

a-cyhalothrin

9844aplusmn101

9514

aplusmn041

9266aplusmn007

000

fplusmn000

000

fplusmn000

000

fplusmn000

9844aplusmn058

9514

aplusmn014

9266bplusmn002

Metho

myl

7715

bplusmn028

7017

dplusmn000

6385eplusmn039

2055aplusmn027

2500aplusmn065

3337

aplusmn234

9770aplusmn048

9516

aplusmn057

9722aplusmn079

Thioph

anate-methyl

8475bplusmn182

7891cplusmn089

7462cplusmn022

514

eplusmn011

819

cplusmn004

2247cplusmn010

8989aplusmn092

8710

bplusmn086

9709aplusmn016

lowastTh

evalues

lowe

rthan

100

meantheno

nextracted

amou

ntof

pesticide

from

Ch-C

uONPsV

aluesa

remeanof

threereplicates

andaregivenas

meanplusmnsta


inthesamecolumn

indicatesig

nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)


Table5Effi

ciency

ofCh

-ZnO

NPs

inadsorptio

nof

different

pesticidesu

singsolid

phasee

xtractioncartrid

getechniqu

e

Pest

icid

esRe

mov

al(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

ent(

)f

ound

inw

aterplusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9872aplusmn531

9315

aplusmn065

9263aplusmn066

000

eplusmn000

184eplusmn018

251

eplusmn006

9872aplusmn405

9499bplusmn026

9515

bplusmn057

Diazino

n9428bplusmn153

7612

bplusmn114

7255cplusmn122

525

bplusmn047

1808bplusmn025

2301bplusmn036

9954aplusmn172

9415

bplusmn042

9556bplusmn089

Fenamipho

s9521bplusmn353

9333

aplusmn092

8720bplusmn044

434

cplusmn036

442

dplusmn013

752d

eplusmn004

9955aplusmn279

9775a

bplusmn068

9472bplusmn040

Imidacloprid

9690a

bplusmn035

9776

aplusmn068

8847bplusmn061

169dplusmn016

221

eplusmn016

1042c

dplusmn007

9958aplusmn022

9997aplusmn076

9888aplusmn027

Lambd

a-cyhalothrin

9909aplusmn078

9800aplusmn161

9447cplusmn041

000

eplusmn000

000

fplusmn000

000

fplusmn000

9909aplusmn055

9800a

bplusmn100

9447bplusmn020

Metho

myl

4147dplusmn108

3851cplusmn031

3662fplusmn056

1809aplusmn027

5782aplusmn025

6259aplusmn033

5956bplusmn118

9633

abplusmn009

9921aplusmn078

Thioph

anate-methyl

9062cplusmn086

6060bplusmn052

6010

eplusmn022

349

cplusmn004

666

cplusmn014

1234cplusmn007

9411


7244cplusmn018

lowastTh

evalues

lowe

rthan

100

meantheno

nextracted

amou

ntof

pesticide

from

Ch-ZnO

NPsV

aluesaremeanof

threereplicates

andaregivenas

meanplusmnsta


inthesamecolumn

indicatesig

nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)


Table6Effi

ciency

ofsta

ndardODScartrid

ge(Sup

elco)inadsorptio

nof

different

pesticidesu

singSP

Etechniqu

e

Pest

icid

esRe

mov

aleffi

cien

cy(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

entf

ound

inw

ater

()plusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9759aplusmn251

954

a 4plusmn048

4811

cplusmn017

0000eplusmn00

428

eplusmn043

1186

dplusmn065

9759aplusmn251

9972aplusmn045

5997cplusmn034

Diazino

n9936aplusmn205

9628aplusmn043

8765aplusmn028

0000eplusmn000

200

fplusmn004

745eplusmn067

9936aplusmn205

9832

aplusmn042

9510

aplusmn047

Fenamipho

s8420bplusmn304

7828bplusmn046

7860bplusmn041

1445aplusmn065

1654bplusmn029

1696cplusmn025

9865aplusmn184

9482aplusmn056

9556aplusmn045

Imidacloprid

8016

bplusmn103

5126cplusmn045

3120dplusmn119

811plusmnd 011

1390cplusmn014

3684aplusmn023

8827aplusmn098

6516

cplusmn034

6804bplusmn071

Lambd

a-cyhalothrin

9388aplusmn121

7205bplusmn246

51709

cplusmn055

0000eplusmn00

742dplusmn034

1064dplusmn065

9388aplusmn121

7947bplusmn149

6243bplusmn060

Metho

myl

4037

dplusmn063

2820dplusmn046

2335dplusmn108

1187

cplusmn087

1399cplusmn087

2298bplusmn098

5224bplusmn076

4219

dplusmn063

4633

dplusmn096

Thioph


7530bplusmn040

7428bplusmn022

1307bplusmn000

1965aplusmn065

2467bplusmn083

9205aplusmn426

9495aplusmn053

9895aplusmn052

lowastTh

evalueslow

erthan

100

meanthen

onextractedam

ount

ofpesticide

from

stand

ardsolid

phasee

xtractioncartrid

geV

aluesa

remeanofthreer

eplicatesandareg

iven

asmeanplusmnsta


inthes


nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)











q = KfC1n (2)

q = qmaxKlC1 + KlC

(3)





4 Conclusion


Data Availability






References





































































Journal of

Chemistry





Journal of

Volume 2018






Volume 2018




Journal of






Enzyme Research


Journal of



MaterialsJournal of






Na

nom

ate

ria

ls








(mV)


Epichlorohydrin











(a)

(a)

(b)

(b)

(c)

(c)

(d)

(d)







300

280

260

240

220

200

180

160

140

120

100

80

60

40

20

Inte

nsity

1000 2000 3000 4000 5000 6000 7000 8000 9000

Position (2)

(a)

Inte

nsity

1000 2000 3000 4000 5000 6000 7000 8000 9000

Position (2)

500

450

400

350

300

250

200

150

100

50

(b)

1000 2000 3000 4000 5000 6000 7000 8000 9000

Inte

nsity

Position (2)

1600

1500

1400

1300

1200

1100

1000

900

800

700

600

500

400

300

200

100

(c)







Chitosan

Ch-CuO NPs

Ch-ZnO NPs

3436

3390

3401

2924

2882

1553

15831410

1407

1067

1070

682

4000 500100020003000

Tran

smitt

ance

()

5855

50

45

40

35

30

25

20

15

10

5

493

1419

2932

2877

16551590 1160

1380

1060

989

10801657

Wavenumber cm-




Term

C

A

B


Factor Name

2571






+ 1551 pH + 0413 Time

S = 1628 and

R2 = 8640

(1)













Table4Effi

ciency

ofCh

-CuO

NPs

inadsorptio

nof

different

pesticidesu

singsolid

phasee

xtractioncartrid

getechniqu

e

Pest

icid

esRe

mov

al(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

ent(

)f

ound

inw

aterplusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9802aplusmn341

9474

aplusmn102

9231

aplusmn023

000

fplusmn000

253

eplusmn047

394

eplusmn009

9802aplusmn455

9727aplusmn135

9625aplusmn013

Diazino

n7015

bplusmn146

3421eplusmn110

2144fplusmn025

1889bplusmn106

1905bplusmn103

2381bplusmn060

8904aplusmn201

5327cplusmn198

4525cplusmn072

Fenamipho

s9533

aplusmn169

9328a

bplusmn099

9044aplusmn104

403

dplusmn018

467

dplusmn015

731dplusmn009

9936aplusmn159

9794aplusmn063

9776

aplusmn032

Imidacloprid

9378aplusmn045

9039

bplusmn061

7291dplusmn030

580

cplusmn028

816

cplusmn009

2596bplusmn096

9958aplusmn022

9975aplusmn049

9887aplusmn058

Lambd

a-cyhalothrin

9844aplusmn101

9514

aplusmn041

9266aplusmn007

000

fplusmn000

000

fplusmn000

000

fplusmn000

9844aplusmn058

9514

aplusmn014

9266bplusmn002

Metho

myl

7715

bplusmn028

7017

dplusmn000

6385eplusmn039

2055aplusmn027

2500aplusmn065

3337

aplusmn234

9770aplusmn048

9516

aplusmn057

9722aplusmn079

Thioph

anate-methyl

8475bplusmn182

7891cplusmn089

7462cplusmn022

514

eplusmn011

819

cplusmn004

2247cplusmn010

8989aplusmn092

8710

bplusmn086

9709aplusmn016

lowastTh

evalues

lowe

rthan

100

meantheno

nextracted

amou

ntof

pesticide

from

Ch-C

uONPsV

aluesa

remeanof

threereplicates

andaregivenas

meanplusmnsta


inthesamecolumn

indicatesig

nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)


Table5Effi

ciency

ofCh

-ZnO

NPs

inadsorptio

nof

different

pesticidesu

singsolid

phasee

xtractioncartrid

getechniqu

e

Pest

icid

esRe

mov

al(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

ent(

)f

ound

inw

aterplusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9872aplusmn531

9315

aplusmn065

9263aplusmn066

000

eplusmn000

184eplusmn018

251

eplusmn006

9872aplusmn405

9499bplusmn026

9515

bplusmn057

Diazino

n9428bplusmn153

7612

bplusmn114

7255cplusmn122

525

bplusmn047

1808bplusmn025

2301bplusmn036

9954aplusmn172

9415

bplusmn042

9556bplusmn089

Fenamipho

s9521bplusmn353

9333

aplusmn092

8720bplusmn044

434

cplusmn036

442

dplusmn013

752d

eplusmn004

9955aplusmn279

9775a

bplusmn068

9472bplusmn040

Imidacloprid

9690a

bplusmn035

9776

aplusmn068

8847bplusmn061

169dplusmn016

221

eplusmn016

1042c

dplusmn007

9958aplusmn022

9997aplusmn076

9888aplusmn027

Lambd

a-cyhalothrin

9909aplusmn078

9800aplusmn161

9447cplusmn041

000

eplusmn000

000

fplusmn000

000

fplusmn000

9909aplusmn055

9800a

bplusmn100

9447bplusmn020

Metho

myl

4147dplusmn108

3851cplusmn031

3662fplusmn056

1809aplusmn027

5782aplusmn025

6259aplusmn033

5956bplusmn118

9633

abplusmn009

9921aplusmn078

Thioph

anate-methyl

9062cplusmn086

6060bplusmn052

6010

eplusmn022

349

cplusmn004

666

cplusmn014

1234cplusmn007

9411


7244cplusmn018

lowastTh

evalues

lowe

rthan

100

meantheno

nextracted

amou

ntof

pesticide

from

Ch-ZnO

NPsV

aluesaremeanof

threereplicates

andaregivenas

meanplusmnsta


inthesamecolumn

indicatesig

nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)


Table6Effi

ciency

ofsta

ndardODScartrid

ge(Sup

elco)inadsorptio

nof

different

pesticidesu

singSP

Etechniqu

e

Pest

icid

esRe

mov

aleffi

cien

cy(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

entf

ound

inw

ater

()plusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9759aplusmn251

954

a 4plusmn048

4811

cplusmn017

0000eplusmn00

428

eplusmn043

1186

dplusmn065

9759aplusmn251

9972aplusmn045

5997cplusmn034

Diazino

n9936aplusmn205

9628aplusmn043

8765aplusmn028

0000eplusmn000

200

fplusmn004

745eplusmn067

9936aplusmn205

9832

aplusmn042

9510

aplusmn047

Fenamipho

s8420bplusmn304

7828bplusmn046

7860bplusmn041

1445aplusmn065

1654bplusmn029

1696cplusmn025

9865aplusmn184

9482aplusmn056

9556aplusmn045

Imidacloprid

8016

bplusmn103

5126cplusmn045

3120dplusmn119

811plusmnd 011

1390cplusmn014

3684aplusmn023

8827aplusmn098

6516

cplusmn034

6804bplusmn071

Lambd

a-cyhalothrin

9388aplusmn121

7205bplusmn246

51709

cplusmn055

0000eplusmn00

742dplusmn034

1064dplusmn065

9388aplusmn121

7947bplusmn149

6243bplusmn060

Metho

myl

4037

dplusmn063

2820dplusmn046

2335dplusmn108

1187

cplusmn087

1399cplusmn087

2298bplusmn098

5224bplusmn076

4219

dplusmn063

4633

dplusmn096

Thioph


7530bplusmn040

7428bplusmn022

1307bplusmn000

1965aplusmn065

2467bplusmn083

9205aplusmn426

9495aplusmn053

9895aplusmn052

lowastTh

evalueslow

erthan

100

meanthen

onextractedam

ount

ofpesticide

from

stand

ardsolid

phasee

xtractioncartrid

geV

aluesa

remeanofthreer

eplicatesandareg

iven

asmeanplusmnsta


inthes


nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)











q = KfC1n (2)

q = qmaxKlC1 + KlC

(3)





4 Conclusion


Data Availability






References





































































Journal of

Chemistry





Journal of

Volume 2018






Volume 2018




Journal of






Enzyme Research


Journal of



MaterialsJournal of






Na

nom

ate

ria

ls





(a)

(a)

(b)

(b)

(c)

(c)

(d)

(d)







300

280

260

240

220

200

180

160

140

120

100

80

60

40

20

Inte

nsity

1000 2000 3000 4000 5000 6000 7000 8000 9000

Position (2)

(a)

Inte

nsity

1000 2000 3000 4000 5000 6000 7000 8000 9000

Position (2)

500

450

400

350

300

250

200

150

100

50

(b)

1000 2000 3000 4000 5000 6000 7000 8000 9000

Inte

nsity

Position (2)

1600

1500

1400

1300

1200

1100

1000

900

800

700

600

500

400

300

200

100

(c)







Chitosan

Ch-CuO NPs

Ch-ZnO NPs

3436

3390

3401

2924

2882

1553

15831410

1407

1067

1070

682

4000 500100020003000

Tran

smitt

ance

()

5855

50

45

40

35

30

25

20

15

10

5

493

1419

2932

2877

16551590 1160

1380

1060

989

10801657

Wavenumber cm-




Term

C

A

B


Factor Name

2571






+ 1551 pH + 0413 Time

S = 1628 and

R2 = 8640

(1)













Table4Effi

ciency

ofCh

-CuO

NPs

inadsorptio

nof

different

pesticidesu

singsolid

phasee

xtractioncartrid

getechniqu

e

Pest

icid

esRe

mov

al(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

ent(

)f

ound

inw

aterplusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9802aplusmn341

9474

aplusmn102

9231

aplusmn023

000

fplusmn000

253

eplusmn047

394

eplusmn009

9802aplusmn455

9727aplusmn135

9625aplusmn013

Diazino

n7015

bplusmn146

3421eplusmn110

2144fplusmn025

1889bplusmn106

1905bplusmn103

2381bplusmn060

8904aplusmn201

5327cplusmn198

4525cplusmn072

Fenamipho

s9533

aplusmn169

9328a

bplusmn099

9044aplusmn104

403

dplusmn018

467

dplusmn015

731dplusmn009

9936aplusmn159

9794aplusmn063

9776

aplusmn032

Imidacloprid

9378aplusmn045

9039

bplusmn061

7291dplusmn030

580

cplusmn028

816

cplusmn009

2596bplusmn096

9958aplusmn022

9975aplusmn049

9887aplusmn058

Lambd

a-cyhalothrin

9844aplusmn101

9514

aplusmn041

9266aplusmn007

000

fplusmn000

000

fplusmn000

000

fplusmn000

9844aplusmn058

9514

aplusmn014

9266bplusmn002

Metho

myl

7715

bplusmn028

7017

dplusmn000

6385eplusmn039

2055aplusmn027

2500aplusmn065

3337

aplusmn234

9770aplusmn048

9516

aplusmn057

9722aplusmn079

Thioph

anate-methyl

8475bplusmn182

7891cplusmn089

7462cplusmn022

514

eplusmn011

819

cplusmn004

2247cplusmn010

8989aplusmn092

8710

bplusmn086

9709aplusmn016

lowastTh

evalues

lowe

rthan

100

meantheno

nextracted

amou

ntof

pesticide

from

Ch-C

uONPsV

aluesa

remeanof

threereplicates

andaregivenas

meanplusmnsta


inthesamecolumn

indicatesig

nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)


Table5Effi

ciency

ofCh

-ZnO

NPs

inadsorptio

nof

different

pesticidesu

singsolid

phasee

xtractioncartrid

getechniqu

e

Pest

icid

esRe

mov

al(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

ent(

)f

ound

inw

aterplusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9872aplusmn531

9315

aplusmn065

9263aplusmn066

000

eplusmn000

184eplusmn018

251

eplusmn006

9872aplusmn405

9499bplusmn026

9515

bplusmn057

Diazino

n9428bplusmn153

7612

bplusmn114

7255cplusmn122

525

bplusmn047

1808bplusmn025

2301bplusmn036

9954aplusmn172

9415

bplusmn042

9556bplusmn089

Fenamipho

s9521bplusmn353

9333

aplusmn092

8720bplusmn044

434

cplusmn036

442

dplusmn013

752d

eplusmn004

9955aplusmn279

9775a

bplusmn068

9472bplusmn040

Imidacloprid

9690a

bplusmn035

9776

aplusmn068

8847bplusmn061

169dplusmn016

221

eplusmn016

1042c

dplusmn007

9958aplusmn022

9997aplusmn076

9888aplusmn027

Lambd

a-cyhalothrin

9909aplusmn078

9800aplusmn161

9447cplusmn041

000

eplusmn000

000

fplusmn000

000

fplusmn000

9909aplusmn055

9800a

bplusmn100

9447bplusmn020

Metho

myl

4147dplusmn108

3851cplusmn031

3662fplusmn056

1809aplusmn027

5782aplusmn025

6259aplusmn033

5956bplusmn118

9633

abplusmn009

9921aplusmn078

Thioph

anate-methyl

9062cplusmn086

6060bplusmn052

6010

eplusmn022

349

cplusmn004

666

cplusmn014

1234cplusmn007

9411


7244cplusmn018

lowastTh

evalues

lowe

rthan

100

meantheno

nextracted

amou

ntof

pesticide

from

Ch-ZnO

NPsV

aluesaremeanof

threereplicates

andaregivenas

meanplusmnsta


inthesamecolumn

indicatesig

nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)


Table6Effi

ciency

ofsta

ndardODScartrid

ge(Sup

elco)inadsorptio

nof

different

pesticidesu

singSP

Etechniqu

e

Pest

icid

esRe

mov

aleffi

cien

cy(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

entf

ound

inw

ater

()plusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9759aplusmn251

954

a 4plusmn048

4811

cplusmn017

0000eplusmn00

428

eplusmn043

1186

dplusmn065

9759aplusmn251

9972aplusmn045

5997cplusmn034

Diazino

n9936aplusmn205

9628aplusmn043

8765aplusmn028

0000eplusmn000

200

fplusmn004

745eplusmn067

9936aplusmn205

9832

aplusmn042

9510

aplusmn047

Fenamipho

s8420bplusmn304

7828bplusmn046

7860bplusmn041

1445aplusmn065

1654bplusmn029

1696cplusmn025

9865aplusmn184

9482aplusmn056

9556aplusmn045

Imidacloprid

8016

bplusmn103

5126cplusmn045

3120dplusmn119

811plusmnd 011

1390cplusmn014

3684aplusmn023

8827aplusmn098

6516

cplusmn034

6804bplusmn071

Lambd

a-cyhalothrin

9388aplusmn121

7205bplusmn246

51709

cplusmn055

0000eplusmn00

742dplusmn034

1064dplusmn065

9388aplusmn121

7947bplusmn149

6243bplusmn060

Metho

myl

4037

dplusmn063

2820dplusmn046

2335dplusmn108

1187

cplusmn087

1399cplusmn087

2298bplusmn098

5224bplusmn076

4219

dplusmn063

4633

dplusmn096

Thioph


7530bplusmn040

7428bplusmn022

1307bplusmn000

1965aplusmn065

2467bplusmn083

9205aplusmn426

9495aplusmn053

9895aplusmn052

lowastTh

evalueslow

erthan

100

meanthen

onextractedam

ount

ofpesticide

from

stand

ardsolid

phasee

xtractioncartrid

geV

aluesa

remeanofthreer

eplicatesandareg

iven

asmeanplusmnsta


inthes


nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)











q = KfC1n (2)

q = qmaxKlC1 + KlC

(3)





4 Conclusion


Data Availability






References





































































Journal of

Chemistry





Journal of

Volume 2018






Volume 2018




Journal of






Enzyme Research


Journal of



MaterialsJournal of






Na

nom

ate

ria

ls





300

280

260

240

220

200

180

160

140

120

100

80

60

40

20

Inte

nsity

1000 2000 3000 4000 5000 6000 7000 8000 9000

Position (2)

(a)

Inte

nsity

1000 2000 3000 4000 5000 6000 7000 8000 9000

Position (2)

500

450

400

350

300

250

200

150

100

50

(b)

1000 2000 3000 4000 5000 6000 7000 8000 9000

Inte

nsity

Position (2)

1600

1500

1400

1300

1200

1100

1000

900

800

700

600

500

400

300

200

100

(c)







Chitosan

Ch-CuO NPs

Ch-ZnO NPs

3436

3390

3401

2924

2882

1553

15831410

1407

1067

1070

682

4000 500100020003000

Tran

smitt

ance

()

5855

50

45

40

35

30

25

20

15

10

5

493

1419

2932

2877

16551590 1160

1380

1060

989

10801657

Wavenumber cm-




Term

C

A

B


Factor Name

2571






+ 1551 pH + 0413 Time

S = 1628 and

R2 = 8640

(1)













Table4Effi

ciency

ofCh

-CuO

NPs

inadsorptio

nof

different

pesticidesu

singsolid

phasee

xtractioncartrid

getechniqu

e

Pest

icid

esRe

mov

al(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

ent(

)f

ound

inw

aterplusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9802aplusmn341

9474

aplusmn102

9231

aplusmn023

000

fplusmn000

253

eplusmn047

394

eplusmn009

9802aplusmn455

9727aplusmn135

9625aplusmn013

Diazino

n7015

bplusmn146

3421eplusmn110

2144fplusmn025

1889bplusmn106

1905bplusmn103

2381bplusmn060

8904aplusmn201

5327cplusmn198

4525cplusmn072

Fenamipho

s9533

aplusmn169

9328a

bplusmn099

9044aplusmn104

403

dplusmn018

467

dplusmn015

731dplusmn009

9936aplusmn159

9794aplusmn063

9776

aplusmn032

Imidacloprid

9378aplusmn045

9039

bplusmn061

7291dplusmn030

580

cplusmn028

816

cplusmn009

2596bplusmn096

9958aplusmn022

9975aplusmn049

9887aplusmn058

Lambd

a-cyhalothrin

9844aplusmn101

9514

aplusmn041

9266aplusmn007

000

fplusmn000

000

fplusmn000

000

fplusmn000

9844aplusmn058

9514

aplusmn014

9266bplusmn002

Metho

myl

7715

bplusmn028

7017

dplusmn000

6385eplusmn039

2055aplusmn027

2500aplusmn065

3337

aplusmn234

9770aplusmn048

9516

aplusmn057

9722aplusmn079

Thioph

anate-methyl

8475bplusmn182

7891cplusmn089

7462cplusmn022

514

eplusmn011

819

cplusmn004

2247cplusmn010

8989aplusmn092

8710

bplusmn086

9709aplusmn016

lowastTh

evalues

lowe

rthan

100

meantheno

nextracted

amou

ntof

pesticide

from

Ch-C

uONPsV

aluesa

remeanof

threereplicates

andaregivenas

meanplusmnsta


inthesamecolumn

indicatesig

nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)


Table5Effi

ciency

ofCh

-ZnO

NPs

inadsorptio

nof

different

pesticidesu

singsolid

phasee

xtractioncartrid

getechniqu

e

Pest

icid

esRe

mov

al(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

ent(

)f

ound

inw

aterplusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9872aplusmn531

9315

aplusmn065

9263aplusmn066

000

eplusmn000

184eplusmn018

251

eplusmn006

9872aplusmn405

9499bplusmn026

9515

bplusmn057

Diazino

n9428bplusmn153

7612

bplusmn114

7255cplusmn122

525

bplusmn047

1808bplusmn025

2301bplusmn036

9954aplusmn172

9415

bplusmn042

9556bplusmn089

Fenamipho

s9521bplusmn353

9333

aplusmn092

8720bplusmn044

434

cplusmn036

442

dplusmn013

752d

eplusmn004

9955aplusmn279

9775a

bplusmn068

9472bplusmn040

Imidacloprid

9690a

bplusmn035

9776

aplusmn068

8847bplusmn061

169dplusmn016

221

eplusmn016

1042c

dplusmn007

9958aplusmn022

9997aplusmn076

9888aplusmn027

Lambd

a-cyhalothrin

9909aplusmn078

9800aplusmn161

9447cplusmn041

000

eplusmn000

000

fplusmn000

000

fplusmn000

9909aplusmn055

9800a

bplusmn100

9447bplusmn020

Metho

myl

4147dplusmn108

3851cplusmn031

3662fplusmn056

1809aplusmn027

5782aplusmn025

6259aplusmn033

5956bplusmn118

9633

abplusmn009

9921aplusmn078

Thioph

anate-methyl

9062cplusmn086

6060bplusmn052

6010

eplusmn022

349

cplusmn004

666

cplusmn014

1234cplusmn007

9411


7244cplusmn018

lowastTh

evalues

lowe

rthan

100

meantheno

nextracted

amou

ntof

pesticide

from

Ch-ZnO

NPsV

aluesaremeanof

threereplicates

andaregivenas

meanplusmnsta


inthesamecolumn

indicatesig

nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)


Table6Effi

ciency

ofsta

ndardODScartrid

ge(Sup

elco)inadsorptio

nof

different

pesticidesu

singSP

Etechniqu

e

Pest

icid

esRe

mov

aleffi

cien

cy(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

entf

ound

inw

ater

()plusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9759aplusmn251

954

a 4plusmn048

4811

cplusmn017

0000eplusmn00

428

eplusmn043

1186

dplusmn065

9759aplusmn251

9972aplusmn045

5997cplusmn034

Diazino

n9936aplusmn205

9628aplusmn043

8765aplusmn028

0000eplusmn000

200

fplusmn004

745eplusmn067

9936aplusmn205

9832

aplusmn042

9510

aplusmn047

Fenamipho

s8420bplusmn304

7828bplusmn046

7860bplusmn041

1445aplusmn065

1654bplusmn029

1696cplusmn025

9865aplusmn184

9482aplusmn056

9556aplusmn045

Imidacloprid

8016

bplusmn103

5126cplusmn045

3120dplusmn119

811plusmnd 011

1390cplusmn014

3684aplusmn023

8827aplusmn098

6516

cplusmn034

6804bplusmn071

Lambd

a-cyhalothrin

9388aplusmn121

7205bplusmn246

51709

cplusmn055

0000eplusmn00

742dplusmn034

1064dplusmn065

9388aplusmn121

7947bplusmn149

6243bplusmn060

Metho

myl

4037

dplusmn063

2820dplusmn046

2335dplusmn108

1187

cplusmn087

1399cplusmn087

2298bplusmn098

5224bplusmn076

4219

dplusmn063

4633

dplusmn096

Thioph


7530bplusmn040

7428bplusmn022

1307bplusmn000

1965aplusmn065

2467bplusmn083

9205aplusmn426

9495aplusmn053

9895aplusmn052

lowastTh

evalueslow

erthan

100

meanthen

onextractedam

ount

ofpesticide

from

stand

ardsolid

phasee

xtractioncartrid

geV

aluesa

remeanofthreer

eplicatesandareg

iven

asmeanplusmnsta


inthes


nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)











q = KfC1n (2)

q = qmaxKlC1 + KlC

(3)





4 Conclusion


Data Availability






References





































































Journal of

Chemistry





Journal of

Volume 2018






Volume 2018




Journal of






Enzyme Research


Journal of



MaterialsJournal of






Na

nom

ate

ria

ls







Chitosan

Ch-CuO NPs

Ch-ZnO NPs

3436

3390

3401

2924

2882

1553

15831410

1407

1067

1070

682

4000 500100020003000

Tran

smitt

ance

()

5855

50

45

40

35

30

25

20

15

10

5

493

1419

2932

2877

16551590 1160

1380

1060

989

10801657

Wavenumber cm-




Term

C

A

B


Factor Name

2571






+ 1551 pH + 0413 Time

S = 1628 and

R2 = 8640

(1)













Table4Effi

ciency

ofCh

-CuO

NPs

inadsorptio

nof

different

pesticidesu

singsolid

phasee

xtractioncartrid

getechniqu

e

Pest

icid

esRe

mov

al(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

ent(

)f

ound

inw

aterplusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9802aplusmn341

9474

aplusmn102

9231

aplusmn023

000

fplusmn000

253

eplusmn047

394

eplusmn009

9802aplusmn455

9727aplusmn135

9625aplusmn013

Diazino

n7015

bplusmn146

3421eplusmn110

2144fplusmn025

1889bplusmn106

1905bplusmn103

2381bplusmn060

8904aplusmn201

5327cplusmn198

4525cplusmn072

Fenamipho

s9533

aplusmn169

9328a

bplusmn099

9044aplusmn104

403

dplusmn018

467

dplusmn015

731dplusmn009

9936aplusmn159

9794aplusmn063

9776

aplusmn032

Imidacloprid

9378aplusmn045

9039

bplusmn061

7291dplusmn030

580

cplusmn028

816

cplusmn009

2596bplusmn096

9958aplusmn022

9975aplusmn049

9887aplusmn058

Lambd

a-cyhalothrin

9844aplusmn101

9514

aplusmn041

9266aplusmn007

000

fplusmn000

000

fplusmn000

000

fplusmn000

9844aplusmn058

9514

aplusmn014

9266bplusmn002

Metho

myl

7715

bplusmn028

7017

dplusmn000

6385eplusmn039

2055aplusmn027

2500aplusmn065

3337

aplusmn234

9770aplusmn048

9516

aplusmn057

9722aplusmn079

Thioph

anate-methyl

8475bplusmn182

7891cplusmn089

7462cplusmn022

514

eplusmn011

819

cplusmn004

2247cplusmn010

8989aplusmn092

8710

bplusmn086

9709aplusmn016

lowastTh

evalues

lowe

rthan

100

meantheno

nextracted

amou

ntof

pesticide

from

Ch-C

uONPsV

aluesa

remeanof

threereplicates

andaregivenas

meanplusmnsta


inthesamecolumn

indicatesig

nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)


Table5Effi

ciency

ofCh

-ZnO

NPs

inadsorptio

nof

different

pesticidesu

singsolid

phasee

xtractioncartrid

getechniqu

e

Pest

icid

esRe

mov

al(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

ent(

)f

ound

inw

aterplusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9872aplusmn531

9315

aplusmn065

9263aplusmn066

000

eplusmn000

184eplusmn018

251

eplusmn006

9872aplusmn405

9499bplusmn026

9515

bplusmn057

Diazino

n9428bplusmn153

7612

bplusmn114

7255cplusmn122

525

bplusmn047

1808bplusmn025

2301bplusmn036

9954aplusmn172

9415

bplusmn042

9556bplusmn089

Fenamipho

s9521bplusmn353

9333

aplusmn092

8720bplusmn044

434

cplusmn036

442

dplusmn013

752d

eplusmn004

9955aplusmn279

9775a

bplusmn068

9472bplusmn040

Imidacloprid

9690a

bplusmn035

9776

aplusmn068

8847bplusmn061

169dplusmn016

221

eplusmn016

1042c

dplusmn007

9958aplusmn022

9997aplusmn076

9888aplusmn027

Lambd

a-cyhalothrin

9909aplusmn078

9800aplusmn161

9447cplusmn041

000

eplusmn000

000

fplusmn000

000

fplusmn000

9909aplusmn055

9800a

bplusmn100

9447bplusmn020

Metho

myl

4147dplusmn108

3851cplusmn031

3662fplusmn056

1809aplusmn027

5782aplusmn025

6259aplusmn033

5956bplusmn118

9633

abplusmn009

9921aplusmn078

Thioph

anate-methyl

9062cplusmn086

6060bplusmn052

6010

eplusmn022

349

cplusmn004

666

cplusmn014

1234cplusmn007

9411


7244cplusmn018

lowastTh

evalues

lowe

rthan

100

meantheno

nextracted

amou

ntof

pesticide

from

Ch-ZnO

NPsV

aluesaremeanof

threereplicates

andaregivenas

meanplusmnsta


inthesamecolumn

indicatesig

nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)


Table6Effi

ciency

ofsta

ndardODScartrid

ge(Sup

elco)inadsorptio

nof

different

pesticidesu

singSP

Etechniqu

e

Pest

icid

esRe

mov

aleffi

cien

cy(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

entf

ound

inw

ater

()plusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9759aplusmn251

954

a 4plusmn048

4811

cplusmn017

0000eplusmn00

428

eplusmn043

1186

dplusmn065

9759aplusmn251

9972aplusmn045

5997cplusmn034

Diazino

n9936aplusmn205

9628aplusmn043

8765aplusmn028

0000eplusmn000

200

fplusmn004

745eplusmn067

9936aplusmn205

9832

aplusmn042

9510

aplusmn047

Fenamipho

s8420bplusmn304

7828bplusmn046

7860bplusmn041

1445aplusmn065

1654bplusmn029

1696cplusmn025

9865aplusmn184

9482aplusmn056

9556aplusmn045

Imidacloprid

8016

bplusmn103

5126cplusmn045

3120dplusmn119

811plusmnd 011

1390cplusmn014

3684aplusmn023

8827aplusmn098

6516

cplusmn034

6804bplusmn071

Lambd

a-cyhalothrin

9388aplusmn121

7205bplusmn246

51709

cplusmn055

0000eplusmn00

742dplusmn034

1064dplusmn065

9388aplusmn121

7947bplusmn149

6243bplusmn060

Metho

myl

4037

dplusmn063

2820dplusmn046

2335dplusmn108

1187

cplusmn087

1399cplusmn087

2298bplusmn098

5224bplusmn076

4219

dplusmn063

4633

dplusmn096

Thioph


7530bplusmn040

7428bplusmn022

1307bplusmn000

1965aplusmn065

2467bplusmn083

9205aplusmn426

9495aplusmn053

9895aplusmn052

lowastTh

evalueslow

erthan

100

meanthen

onextractedam

ount

ofpesticide

from

stand

ardsolid

phasee

xtractioncartrid

geV

aluesa

remeanofthreer

eplicatesandareg

iven

asmeanplusmnsta


inthes


nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)











q = KfC1n (2)

q = qmaxKlC1 + KlC

(3)





4 Conclusion


Data Availability






References





































































Journal of

Chemistry





Journal of

Volume 2018






Volume 2018




Journal of






Enzyme Research


Journal of



MaterialsJournal of






Na

nom

ate

ria

ls















Table4Effi

ciency

ofCh

-CuO

NPs

inadsorptio

nof

different

pesticidesu

singsolid

phasee

xtractioncartrid

getechniqu

e

Pest

icid

esRe

mov

al(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

ent(

)f

ound

inw

aterplusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9802aplusmn341

9474

aplusmn102

9231

aplusmn023

000

fplusmn000

253

eplusmn047

394

eplusmn009

9802aplusmn455

9727aplusmn135

9625aplusmn013

Diazino

n7015

bplusmn146

3421eplusmn110

2144fplusmn025

1889bplusmn106

1905bplusmn103

2381bplusmn060

8904aplusmn201

5327cplusmn198

4525cplusmn072

Fenamipho

s9533

aplusmn169

9328a

bplusmn099

9044aplusmn104

403

dplusmn018

467

dplusmn015

731dplusmn009

9936aplusmn159

9794aplusmn063

9776

aplusmn032

Imidacloprid

9378aplusmn045

9039

bplusmn061

7291dplusmn030

580

cplusmn028

816

cplusmn009

2596bplusmn096

9958aplusmn022

9975aplusmn049

9887aplusmn058

Lambd

a-cyhalothrin

9844aplusmn101

9514

aplusmn041

9266aplusmn007

000

fplusmn000

000

fplusmn000

000

fplusmn000

9844aplusmn058

9514

aplusmn014

9266bplusmn002

Metho

myl

7715

bplusmn028

7017

dplusmn000

6385eplusmn039

2055aplusmn027

2500aplusmn065

3337

aplusmn234

9770aplusmn048

9516

aplusmn057

9722aplusmn079

Thioph

anate-methyl

8475bplusmn182

7891cplusmn089

7462cplusmn022

514

eplusmn011

819

cplusmn004

2247cplusmn010

8989aplusmn092

8710

bplusmn086

9709aplusmn016

lowastTh

evalues

lowe

rthan

100

meantheno

nextracted

amou

ntof

pesticide

from

Ch-C

uONPsV

aluesa

remeanof

threereplicates

andaregivenas

meanplusmnsta


inthesamecolumn

indicatesig

nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)


Table5Effi

ciency

ofCh

-ZnO

NPs

inadsorptio

nof

different

pesticidesu

singsolid

phasee

xtractioncartrid

getechniqu

e

Pest

icid

esRe

mov

al(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

ent(

)f

ound

inw

aterplusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9872aplusmn531

9315

aplusmn065

9263aplusmn066

000

eplusmn000

184eplusmn018

251

eplusmn006

9872aplusmn405

9499bplusmn026

9515

bplusmn057

Diazino

n9428bplusmn153

7612

bplusmn114

7255cplusmn122

525

bplusmn047

1808bplusmn025

2301bplusmn036

9954aplusmn172

9415

bplusmn042

9556bplusmn089

Fenamipho

s9521bplusmn353

9333

aplusmn092

8720bplusmn044

434

cplusmn036

442

dplusmn013

752d

eplusmn004

9955aplusmn279

9775a

bplusmn068

9472bplusmn040

Imidacloprid

9690a

bplusmn035

9776

aplusmn068

8847bplusmn061

169dplusmn016

221

eplusmn016

1042c

dplusmn007

9958aplusmn022

9997aplusmn076

9888aplusmn027

Lambd

a-cyhalothrin

9909aplusmn078

9800aplusmn161

9447cplusmn041

000

eplusmn000

000

fplusmn000

000

fplusmn000

9909aplusmn055

9800a

bplusmn100

9447bplusmn020

Metho

myl

4147dplusmn108

3851cplusmn031

3662fplusmn056

1809aplusmn027

5782aplusmn025

6259aplusmn033

5956bplusmn118

9633

abplusmn009

9921aplusmn078

Thioph

anate-methyl

9062cplusmn086

6060bplusmn052

6010

eplusmn022

349

cplusmn004

666

cplusmn014

1234cplusmn007

9411


7244cplusmn018

lowastTh

evalues

lowe

rthan

100

meantheno

nextracted

amou

ntof

pesticide

from

Ch-ZnO

NPsV

aluesaremeanof

threereplicates

andaregivenas

meanplusmnsta


inthesamecolumn

indicatesig

nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)


Table6Effi

ciency

ofsta

ndardODScartrid

ge(Sup

elco)inadsorptio

nof

different

pesticidesu

singSP

Etechniqu

e

Pest

icid

esRe

mov

aleffi

cien

cy(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

entf

ound

inw

ater

()plusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9759aplusmn251

954

a 4plusmn048

4811

cplusmn017

0000eplusmn00

428

eplusmn043

1186

dplusmn065

9759aplusmn251

9972aplusmn045

5997cplusmn034

Diazino

n9936aplusmn205

9628aplusmn043

8765aplusmn028

0000eplusmn000

200

fplusmn004

745eplusmn067

9936aplusmn205

9832

aplusmn042

9510

aplusmn047

Fenamipho

s8420bplusmn304

7828bplusmn046

7860bplusmn041

1445aplusmn065

1654bplusmn029

1696cplusmn025

9865aplusmn184

9482aplusmn056

9556aplusmn045

Imidacloprid

8016

bplusmn103

5126cplusmn045

3120dplusmn119

811plusmnd 011

1390cplusmn014

3684aplusmn023

8827aplusmn098

6516

cplusmn034

6804bplusmn071

Lambd

a-cyhalothrin

9388aplusmn121

7205bplusmn246

51709

cplusmn055

0000eplusmn00

742dplusmn034

1064dplusmn065

9388aplusmn121

7947bplusmn149

6243bplusmn060

Metho

myl

4037

dplusmn063

2820dplusmn046

2335dplusmn108

1187

cplusmn087

1399cplusmn087

2298bplusmn098

5224bplusmn076

4219

dplusmn063

4633

dplusmn096

Thioph


7530bplusmn040

7428bplusmn022

1307bplusmn000

1965aplusmn065

2467bplusmn083

9205aplusmn426

9495aplusmn053

9895aplusmn052

lowastTh

evalueslow

erthan

100

meanthen

onextractedam

ount

ofpesticide

from

stand

ardsolid

phasee

xtractioncartrid

geV

aluesa

remeanofthreer

eplicatesandareg

iven

asmeanplusmnsta


inthes


nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)











q = KfC1n (2)

q = qmaxKlC1 + KlC

(3)





4 Conclusion


Data Availability






References





































































Journal of

Chemistry





Journal of

Volume 2018






Volume 2018




Journal of






Enzyme Research


Journal of



MaterialsJournal of






Na

nom

ate

ria

ls





Table5Effi

ciency

ofCh

-ZnO

NPs

inadsorptio

nof

different

pesticidesu

singsolid

phasee

xtractioncartrid

getechniqu

e

Pest

icid

esRe

mov

al(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

ent(

)f

ound

inw

aterplusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9872aplusmn531

9315

aplusmn065

9263aplusmn066

000

eplusmn000

184eplusmn018

251

eplusmn006

9872aplusmn405

9499bplusmn026

9515

bplusmn057

Diazino

n9428bplusmn153

7612

bplusmn114

7255cplusmn122

525

bplusmn047

1808bplusmn025

2301bplusmn036

9954aplusmn172

9415

bplusmn042

9556bplusmn089

Fenamipho

s9521bplusmn353

9333

aplusmn092

8720bplusmn044

434

cplusmn036

442

dplusmn013

752d

eplusmn004

9955aplusmn279

9775a

bplusmn068

9472bplusmn040

Imidacloprid

9690a

bplusmn035

9776

aplusmn068

8847bplusmn061

169dplusmn016

221

eplusmn016

1042c

dplusmn007

9958aplusmn022

9997aplusmn076

9888aplusmn027

Lambd

a-cyhalothrin

9909aplusmn078

9800aplusmn161

9447cplusmn041

000

eplusmn000

000

fplusmn000

000

fplusmn000

9909aplusmn055

9800a

bplusmn100

9447bplusmn020

Metho

myl

4147dplusmn108

3851cplusmn031

3662fplusmn056

1809aplusmn027

5782aplusmn025

6259aplusmn033

5956bplusmn118

9633

abplusmn009

9921aplusmn078

Thioph

anate-methyl

9062cplusmn086

6060bplusmn052

6010

eplusmn022

349

cplusmn004

666

cplusmn014

1234cplusmn007

9411


7244cplusmn018

lowastTh

evalues

lowe

rthan

100

meantheno

nextracted

amou

ntof

pesticide

from

Ch-ZnO

NPsV

aluesaremeanof

threereplicates

andaregivenas

meanplusmnsta


inthesamecolumn

indicatesig

nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)


Table6Effi

ciency

ofsta

ndardODScartrid

ge(Sup

elco)inadsorptio

nof

different

pesticidesu

singSP

Etechniqu

e

Pest

icid

esRe

mov

aleffi

cien

cy(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

entf

ound

inw

ater

()plusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9759aplusmn251

954

a 4plusmn048

4811

cplusmn017

0000eplusmn00

428

eplusmn043

1186

dplusmn065

9759aplusmn251

9972aplusmn045

5997cplusmn034

Diazino

n9936aplusmn205

9628aplusmn043

8765aplusmn028

0000eplusmn000

200

fplusmn004

745eplusmn067

9936aplusmn205

9832

aplusmn042

9510

aplusmn047

Fenamipho

s8420bplusmn304

7828bplusmn046

7860bplusmn041

1445aplusmn065

1654bplusmn029

1696cplusmn025

9865aplusmn184

9482aplusmn056

9556aplusmn045

Imidacloprid

8016

bplusmn103

5126cplusmn045

3120dplusmn119

811plusmnd 011

1390cplusmn014

3684aplusmn023

8827aplusmn098

6516

cplusmn034

6804bplusmn071

Lambd

a-cyhalothrin

9388aplusmn121

7205bplusmn246

51709

cplusmn055

0000eplusmn00

742dplusmn034

1064dplusmn065

9388aplusmn121

7947bplusmn149

6243bplusmn060

Metho

myl

4037

dplusmn063

2820dplusmn046

2335dplusmn108

1187

cplusmn087

1399cplusmn087

2298bplusmn098

5224bplusmn076

4219

dplusmn063

4633

dplusmn096

Thioph


7530bplusmn040

7428bplusmn022

1307bplusmn000

1965aplusmn065

2467bplusmn083

9205aplusmn426

9495aplusmn053

9895aplusmn052

lowastTh

evalueslow

erthan

100

meanthen

onextractedam

ount

ofpesticide

from

stand

ardsolid

phasee

xtractioncartrid

geV

aluesa

remeanofthreer

eplicatesandareg

iven

asmeanplusmnsta


inthes


nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)











q = KfC1n (2)

q = qmaxKlC1 + KlC

(3)





4 Conclusion


Data Availability






References





































































Journal of

Chemistry





Journal of

Volume 2018






Volume 2018




Journal of






Enzyme Research


Journal of



MaterialsJournal of






Na

nom

ate

ria

ls





Table6Effi

ciency

ofsta

ndardODScartrid

ge(Sup

elco)inadsorptio

nof

different

pesticidesu

singSP

Etechniqu

e

Pest

icid

esRe

mov

aleffi

cien

cy(

)plusmnSE

atth

reel

evel

sofc

once

ntra

tion

(mg

L)A

ctiv

eing

redi

entf

ound

inw

ater

()plusmn

SETo

talf

ound

()lowastplusmn

SE(E

xtra

cted

inm

etha

nol

acet

onitr

ile)

(Rem

aini

ngin

wat

ersa

mpl

e)10

5010

010

5010

010

5010

0Ab

amectin

9759aplusmn251

954

a 4plusmn048

4811

cplusmn017

0000eplusmn00

428

eplusmn043

1186

dplusmn065

9759aplusmn251

9972aplusmn045

5997cplusmn034

Diazino

n9936aplusmn205

9628aplusmn043

8765aplusmn028

0000eplusmn000

200

fplusmn004

745eplusmn067

9936aplusmn205

9832

aplusmn042

9510

aplusmn047

Fenamipho

s8420bplusmn304

7828bplusmn046

7860bplusmn041

1445aplusmn065

1654bplusmn029

1696cplusmn025

9865aplusmn184

9482aplusmn056

9556aplusmn045

Imidacloprid

8016

bplusmn103

5126cplusmn045

3120dplusmn119

811plusmnd 011

1390cplusmn014

3684aplusmn023

8827aplusmn098

6516

cplusmn034

6804bplusmn071

Lambd

a-cyhalothrin

9388aplusmn121

7205bplusmn246

51709

cplusmn055

0000eplusmn00

742dplusmn034

1064dplusmn065

9388aplusmn121

7947bplusmn149

6243bplusmn060

Metho

myl

4037

dplusmn063

2820dplusmn046

2335dplusmn108

1187

cplusmn087

1399cplusmn087

2298bplusmn098

5224bplusmn076

4219

dplusmn063

4633

dplusmn096

Thioph


7530bplusmn040

7428bplusmn022

1307bplusmn000

1965aplusmn065

2467bplusmn083

9205aplusmn426

9495aplusmn053

9895aplusmn052

lowastTh

evalueslow

erthan

100

meanthen

onextractedam

ount

ofpesticide

from

stand

ardsolid

phasee

xtractioncartrid

geV

aluesa

remeanofthreer

eplicatesandareg

iven

asmeanplusmnsta


inthes


nificantd

ifferencesa

ccording

toStud

ent-N

ewman-K

euls(SNK)test(Ple

005)











q = KfC1n (2)

q = qmaxKlC1 + KlC

(3)





4 Conclusion


Data Availability






References





































































Journal of

Chemistry





Journal of

Volume 2018






Volume 2018




Journal of






Enzyme Research


Journal of



MaterialsJournal of






Na

nom

ate

ria

ls














q = KfC1n (2)

q = qmaxKlC1 + KlC

(3)





4 Conclusion


Data Availability






References





































































Journal of

Chemistry





Journal of

Volume 2018






Volume 2018




Journal of






Enzyme Research


Journal of



MaterialsJournal of






Na

nom

ate

ria

ls







4 Conclusion


Data Availability






References





































































Journal of

Chemistry





Journal of

Volume 2018






Volume 2018




Journal of






Enzyme Research


Journal of



MaterialsJournal of






Na

nom

ate

ria

ls

































































Journal of

Chemistry





Journal of

Volume 2018






Volume 2018




Journal of






Enzyme Research


Journal of



MaterialsJournal of






Na

nom

ate

ria

ls




Development of a Solid-Phase Extraction (SPE)...

Documents

Transcript of Development of a Solid-Phase Extraction (SPE)...