A Literature Review OnTHE FORMULATION AND CHARECTERISATION OF NIOSOMES FOR TRANSDERMAL DRUG DELIVERY

By

MUBASHIR (REG NO:100060077)SANA.K.MOIDEEN (REG NO: 100060092)SHAMEEMUNISA HAMZA M T(REG NO:100060104)

Dissertation submitted to the

KERALA UNIVERSITY OF HEALTH SCIENCES, ThrissurIn partial fulfillment of the requirements for the degree of

BACHELOR OFPHARMACY

Under the guidance of

Mr.SHERON JOSEPH,M.pharm,Sr.LecturerDepartment of pharmaceuticsAl-Shifa College of Pharmacy

AL-SHIFA COLLEGE OF PHARMACY, POONTHAVANAM(P.O), MALAPPURAM

KERALA UNIVERSITY OF HEALTH SCIENCES

DECLARATION BY THE CANDIDATES

We hereby declare that this dissertation entitled The formulation and charecterisation of niosomes for transdermal drug delivery submitted to Kerala University of Health Sciences, Thrissur, is a bonafide and genuine project work carried out by us in the library of Al-Shifa College of Pharmacy, Perinthalmanna, under the guidance of Mr. Sheron Joseph, Sr.Lecturer, Department of Pharmaceutics. We also declare that the matter embodied in it is original and the same has not previously formed the basis for the award of any degree, diploma, associate ship or fellowship of any other university or institution.Date:Place: Perinthalmanna. MUBASHIR SANA .K.MOIDEEN SHAMEEMUNNISA HAMZA M T

AL-SHIFA COLLEGE OF PHARMACY PERINTHALMANNA, MALAPPURAM

CERTIFICATE BY THE GUIDE

This is to certify that the dissertation entitled The formulation and charecterisation of niosomes for transdermal drug deliveryis a bonafide research work done by Mubashir ,Sana.k.moideen and shameemunisa hamza in partial fulfillment of the requirement for the award of degree of Bachelor of Pharmacy of Kerala University of Health Science, Thrissur. This work was carried out by them in the library of Al-Shifa College of Pharmacy, Perinthalmanna, under my guidance and direct supervision.

Date:Mr.Sheron Joseph

Place: PerinthalmannaM.Pharm, Sr.Lecturer

Department of Pharmaceutics

Al-ShifaCollege of Pharmacy, Perinthalmanna

AL-SHIFA COLLEGE OF PHARMACY PERINTHALMANNA, MALAPPURAM

CERTIFICATE

This is to certify that the dissertation entitled The formulation and charecterisation of niosomes for transdermal drug deliveryis a bonafide research work done by Mubashir ,Sana K. Moideen and Shameemunnisa Hamza M T in partial fulfillment of the requirement for the award of degree of Bachelor of Pharmacy of Kerala University of Health Science, Thrissur. This work was carried out by them in the library of Al-Shifa College of Pharmacy, Perinthalmanna, under my guidance and direct supervision.

Date:Place:PerinthalmannaProf (Dr) T. N. K.Suriya Prakash,

(M Pharm, Ph D, PGDPL),

Principal, Al-Shifa College of Pharmacy, Perinthalmannna

AL-SHIFA COLLEGE OF PHARMACY PERINTHALMANNA, MALAPPURAM

ENDORSEMENT BY THE PRINCIPAL

This is to certify that the project work entitled The formulation and charecterisation of niosomes for transdermal drug delivery by Mubashir, Sana.k.moideen and Shameemunisa hamza M T of final year B.Pharm, Al-Shifa College of Pharmacy as a partial fulfilment of the award of the degree of pharmacy has beendone under the supervision and guidance of Mr. Sheron Joseph, Dept. of Pharmaceutics, Al-Shifa College of Pharmacy, Perinthalmanna.

Date:

Place: Perinthalmanna Prof (Dr) T. N. K.Suriya Prakash,

(M Pharm, Ph D, PGDPL),

Principal, Al-Shifa College of Pharmacy, Perinthalmanna.

ACKNOLWEDGEMENTWe tender our deep and sincere gratitude and indebtedness to our esteemed teacher and guide Mr.Sheron Joseph, M.Pharm, Department of Pharmaceutics, Al Shifa College of Pharmacy, Perinthalmanna for his excellent guidance, valuable suggestions, constant inspiration and sustained interest throughout our work.We wish to express our sincere thanks to our beloved Principal,(Dr).T.N.K. Suriyaprakash, M.Pharm, Ph.D, PGDPL. Al Shifa College ofPharmacy, Perinthalmanna for his co- operation and leading all the facilitiesrequired to proceed with our study.We would like to express our sincere thanks to Mr. Junaise vazhayil,Department of Pharmaceutics, for his timely valuable help during our work. Thanks to all our teachers for their help.We express our sincere thanks to our classmates who helped us during our work. We bow to our affectionate parents and family members for their selfless love, blessing which had been instrumental in completing this task.We submit our thanks to managing trustee Mr.P. Unneen, Shifa MedicalTrust for providing all facilities of the institution. Also we extend our thanksto librarian Mr.V. Firoz Babu and all other non-teaching staff for theirvaluable help and support during the work. Mubashir Sana.k.moideen Shameemunnisa hamza M T

CONTENTSSL.NO.TOPICSPAGE NO.

1INTRODUCTION

2REVIEW OF ARTICLES

3CONCLUSION

4BIBILIOGRAPHY

NIOSOMESINTRODUCTIONNiosome are the non-ionic surfactant vesicles which can entrap both hydrophilic and lipophilic drugs, either in aqueous layer or in vesicular membrane made of lipid materials. It has better stability than liposomes it prolongs the circulation of entrapped drugs. Because of the presence of non-ionic surfactant with the lipid,there is better targeting of drugs to tumour,liver, and brain.It is very useful for targeting the drugs for treating cancer, or parasitic, viral and other microbial diseases more effectively.Non-phospholipids vesicular system have been studied for many years and have largely involved in the investigation of the dialkyldimethyl ammonium salts and other ionic amphiphiles.most of the amphiphiles are toxic and are unsuitable for use as drug carriers. Niosomes are used to attain different drug distribution and release characteristics with the help of surfactants. Niosomes may suffer uptake by the RES and methotrexate and sodium stilbogluconate where found to accommodate in liver following administation as niosomes. The absence of accumulation of drugs in the liver supports the evidence of sustained plasma levels of drugs resulting from slow release of circulating rather than trapped vescicles.The larger niosomes may be accumulate in the liver or spleen and may be filtered out in the passage through the lung capillary network. In the treatment of parasitic infection of liver,spleen and bone marrrow,niosomes made. Inclution of cholesterol in the precaution of niosomes has been demonstrated to alter the properties of niosomes and markedly decreasing the efflux of entraped solid.Non ionic surfactant vesicles as vehicle for drug formulation may reduce the systemic toxicity of many anticancer and anti infective drugs. Niosomes as carriers for enhance delivery to specific cells may improve the therapeutic index by restricting drug effect to target cells. They are nontoxic and biodegradable. Many nonionic surfactants like tweens and spans, cationic surfactants like cetrimide,sodiumdodecylsulfate are used with cholestrol to entrape drugs in vesicles. Liver can act as a depot for many drugs where niosomescontaing drugs may be takern up and broken down by lysosomal lipase slowely to release free drug and re-enter the circulation.Niosomes are slowly degraded providing a more sustained effect. Niosomes are found to have selective drug delivery potential for cutaneous application of 5-alpha dihydrotestosterone,triamicilonoloneacetonide and iv administration of methotrexate for cancer treatment and sodium stilbogluconate in the treatment of leishmaniasis etc. METHODS OF PREPARATIONS EVALUATIONS AND CHARACTERISATIONNiosomes can be formulated by lipid layer hydration method,reverse phase evaporation techiques or by trans-membrane ph gradient uptake process (remote loading). Niosomes can be characterised by there size distribution studies drug entrapment,drugstability,drug leakage in saline and plasma on storage,pharmakokineticaspects,toxicity studies and drug targeting efficiency etc.are sign of the evaluation parameters.The use of niosomes as drug delivery vehicles assumes an ability to efficiently load the niosomal system with the drug of choice.passive trapping technique and active trapping procedures(remote loading) are the two members employed for loading drug in to the niosomes.Selection of an encapsulation protocol is largely detacted by concern such as encapsulation efficiency,drug or lipid ratio drug retention,base 1 preparation,sterility,costefficiany as well as drug stability.Passive trapping techniquesPassive trapping procedures include all technichques that have been employed to entrap drugs in niosomal systems. Passive trapping means that the drug and the lipid are codispersed with a fraction of the drug being entrapped according to hydrophobic and electrostatic consideratons. Entrapped hydrophilic drug will be associated with the internal aquoesphases,hydrophobic drug will partition primarily to the hydrocarbon region of the membrane and enhanced entrapment of charged drug partitioning in to the lipid water interface regions if lipids of opposite charge are present in the niosomes bilayer. Of the different passive trapping techniques, only the freeze thaw procedure can provide trapping efficeincies in the range of 90%,and that only when high lipid concentrations are used to provided the agent to be entrapped should be highly water soluble.ifnot,it is difficult to achieve high drug or lipid ratios by this procedures.the SUV produced by French Press procedures, can exhibit trapping efficiency up to 25%,but this value decreases for higher molecular weight compounds.Advantages include the lack of protein denaturation and longer retention times for entrapped solute. Freezing and thawing SUV results in dramatic increase in vesicle size and trapped volume this procedure can also be used to produce MLV exhibiting trapping efficiencies of 50% or more without effecting the activities of agents such as DNA and protein. Similarly,encapsulation efficiencies of 50% for MLV can also be obtained by dehydration-rehydration procedures. The advantages of freeze-thaw and rehydration dehydration are.. Large trapping efficiency. Can be applied to large number of biologicaly active agents. Produce MLV that exhibits stable solute retentions,charactistics. Are relatively simple. Donot require organic solvents or detergents. Display extended storage stabilities in the frozen to dried state. A negative point of these procedures are niosomes formed are of heterogenousdistributions.More homogenous sized vesicles can be achieved by subsequently extruding the MLV dispersions through filteres of various pore size under moderate pressures. The trapping efficiencies of this vesicles by extrution technique can be substantial,the vesicles display excellent retention of entrapped solute,degradation of protein and DNA is negligible,extrution renters the preparation sterile and scale up would appear straight forward. Solvent evaporation technique employing ether(reverse phase evaporation)are useful forentrapping drugs on LUV. Lipids dissolved in ether are mixed with aqueos phase (containing the agents to be entrapped) and removal of organic solvent by heat,,by reduced pressure or by both induces the spontaneous formation of LUV.This procedure is trapping efficiencies up to 45%for a wide range of solvents. A disadvantange of solvent based liposomes is that some macromolecules are denaturated by this procedures. Active trapping techniquesAn exciting recent devolopment concern loading of lipophilic cationic drugs in to niosomes is the active trapping that can be achieved in response to ion gradients placed across niosomalmembrane.Thisability ,which is also refered to as remote loading, allows drug entrapment. After the niosomal carrier has been generated. The mechanism of drug uptake induced by ph gradients is probably similar to ph gradient dependendtransmembraneredisrtibution of weak bases. This procedure offers a superior methods for loading lipophilic cationic drugs in to niosomes nearing 100% entrapment efficiency. In addition it results in drug lipid ratios which are significantly greater than possible by any other method. Beside being extremely cost efficient,this method of entrapment also decreases rate of drug efflux from the vesicle by as much as 30 fold. The properties of niosomes, their charge,chemicalreactivity,stability and biological characteristics are determined by preparation processes and choice of chemical constituents.The three major types of niosomes-multi lamellar vesicles(MLV), small unilamellar vesicles (SUV) and large unilamellar vesicles (LUV). Multi lamellar vesicles that result in increased trapped volumes and equilibrium solute distributers include hand shaken MLV with variations in lipid compositions, hydration from organic solvent, dehydration-rehydration procedure and freeze-thawing. Small unilamellar vesicles are commonly produced by sonication and french press procedure. Ultra sonic electro capillary emulsification or solvent dilution techniques can be used to prepare SUV. The injection of lipid solubilised in an organic solvent into an aqueous buffer can result in the spontaneous formation of LUV. But the better method that is widely accepted for generating LUV is by reverse phase evaporation. LUV can also be formed by solubilising lipid in an aqueous buffer that contains detergents.

NIOSOME DELIVERY APPLICATIONSA variety of non ionic surfactant vesicles employed as drug, vaccine and imaging agent delivery systems. The most popular surfactants used are the sorbitanamphiphiles (span 20, span 40, span 60 and span 80) which are approved excipients. DRUG TARGETINGAnticancer drugsAnti-cancer drugs such as the model drug doxorubicin, when encapsulated in sorbitan mono stearate poly (oxyethylene) coated (coated with solulan C24) niosomes, circulate for prolonged periods.These particles circulate for prolonged periods due to the poly (oxyethylene) coating, which prevents particle recognition and the uptake by the liver and spleen. However while a poly(oxyethylene) coat may improve the delivery of drugs to tumors by achieving long blood circulation times, niosomes devoid of poly(oxyethylene) coatings are also able to improve the tumoricidal activity of drugs such as doxorubicin, methotrixate and vincristin, principally by altering drug bio distribution following intraveneous administration such that the drug is targeted to some extend to the tumor tissue.Anti-infectiveThe targeting of anti-leishmanial drugs to the liver, the site of pathology, is achievable with niosomal formulations. The niosomes are thought to be taken up by macrophages in the liver. The anti-parasitic activity of sodium stilbogluconate is increased ten fold by encapsulation into niosomes.DELIVERY TO THE BRAINDelivery of peptides to area beyond the blood brain barrier is a major challenge, however, there is evidence that glucose coated niosomes may be able to achieve brain delivery of hydrophillic peptides.

TOPICAL USE OF NIOSOMESTransdermalThe topical application of niosomes encapsulated drugs results in the enhanced delivery of drugs through the stratum corneum and delivery is specifically enhanced when hydrophillic surfactants such as poly(oxyethylene)-7-dodecylether are used to produce flexible vesicles, which have similar flexible bilayer properties to the phospholipid transfersomes.OcularNiosomal formulation for the topical treatment of glaucoma have emerged in the form of carbopol 934P coated sorbitanmonostearateazetazolamideniosomes both chitosan and carbopol 934P coated sorbitan mono stearate timolol maleate niosomes and sorbitan mono palmitatetimolol maleate discomes.

NIOSOMAL VACCINESThe niosomal encapsulation of both antigens and DNA encoding for antigens results in an enhancement of the humoral and cellular immune response to the said antigens.

NIOSOMES AS IMAGING AGENTSTargeting tumor glucose receptors is a viable method of imaging tumors. N-palmitoyilglucasamineniosomescaoted with poly(oxyethylene) and encapsulating gadolinium salts target PC# tumor cells on tail vain injection.

AIMTo carry out review of literature for the formulation and characterisation of niosomes for transdermal drug delivery.

REVIEW ARTICLE

Int J Pharm. 2009 Jul 30;377(1-2):1-8. 1Formulation and in vitro assessment of minoxidilniosomes for enhanced skin delivery.(Balakrishnan P1, Shanmugam S, Lee WS, Lee WM, Kim JO, Oh DH, Kim DD, Kim JS, Yoo BK, Choi HG, Woo JS, Yong CS.AbstractBalakrishnan P.et.al.suggests that niosomes improve the low skin penetration and bioavailability characteristics shown by conventional topical vehicle for minoxidil. Niosomes formed from polyoxyethylene alkyl ethers (Brij) or sorbitan monoesters (Span) with cholesterol molar ratios of 0, 1 and 1.5 were prepared with varying drug amount 20-50mg using thin film-hydration method. The prepared systems were characterized for entrapment efficiency, particle size, zeta potential and stability. Skin permeation studies were performed using static vertical diffusion Franz cells and hairless mouse skin treated with either niosomes, control minoxidil solution (propylene glycol-water-ethanol at 20:30:50, v/v/v) or a leading topical minoxidil commercial formulation (Minoxyl). The results showed that the type of surfactant, cholesterol and incorporated amount of drug altered the entrapment efficiency of niosomes. Higher entrapment efficiency was obtained with the niosomes prepared from Span 60 and cholesterol at 1:1 molar ratio using 25mg drug. Niosomal formulations have shown a fairly high retention of minoxidil inside the vesicles (80%) at refrigerated temperature up to a period of 3 months. It was observed that both dialyzed and non-dialyzed niosomal formulations (1.03+/-0.18 to 19.41+/-4.04%) enhanced the percentage of dose accumulated in the skin compared to commercial and control formulations (0.11+/-0.03 to 0.48+/-0.17%) except dialyzed Span 60 niosomes. The greatest skin accumulation was always obtained with non-dialyzed vesicular formulations. Balakrishnan P.et.al. suggest that these niosomal formulations could constitute a promising approach for the topical delivery of minoxidil in hair loss treatment.2Indian J Exp Biol.2011 Jun;49(6):438-45.2 Sorbitan ester niosomes for topical delivery of rofecoxib.Das MK1,Palei NN.The aim of the present investigation is to encapsulate rofecoxib in niosomes and incorporate the prepared niosomes into dermal gel base for sustained therapeutic action. Niosomes were prepared by lipid film hydration technique and were analyzed for size, entrapment efficiency and drug retention capacity. Niosomal vesicles were then incorporated into blank carbopol gel to form niosomal gel. The in vitro permeation study across pig skin was performed using Keshary-Chien glass diffusion cell. The size and entrapment efficiency of the niosomal vesicles increased with gradual increase in HLB value of nonionic surfactants used. Maximum drug entrapment was observed with Span 20 with HLB value of 8.6 and drug leakage from vesicles was less at refrigerated condition than at the room temperature. Higher proportion of cholesterol made the niosomal formulation more stable with high drug retention properties. The niosomal gel showed a prolong drug release behavior compared to plain drug gel. Differential scanning calorimetric study of drug loaded gel and pig skin after permeation study confirmed inertness of carbopol gel base toward rofecoxib and absence of drug metabolism in the skin during permeation study, respectively. The niosomal formulations were successfully prepared by lipid film hydration technique using cholesterol and Span as nonionic surfactant. Presence of cholesterol made niosomes more stable with high drug entrapment efficiency and retention properties.Das MK and Palei NN reported that the lower flux value of niosomal gel as compared to plain drug gel across pig skin assured the prolong drug release behavior with sustained action.3J Pharm Bioallied Sci.2013 Oct;5(4):318-25. doi: 10.4103/0975-7406.120080.

3 Evaluation of proniosomes as an alternative strategy to optimize piroxicam transdermal delivery.Alsarra IA.The current investigation aims to evaluate the transdermal potential of niosomes bearing a potent non-steroidal anti-inflammatory, piroxicam. Piroxicam-loaded niosomes were prepared and characterized for surface morphology, entrapment efficiency and in vitro permeation across excised rat skin from various proniosome gel formulations using Franz diffusion cells. Various non-ionic surfactants were used to achieve optimum encapsulation efficiency. The prepared proniosomes significantly improved drug permeation and reduced the lag time (p < 0.05). Proniosomes prepared with Span 60 provided a higher piroxicam flux across the skin than did those prepared with Tween 80. Niosomes prepared using Span 60 showed a higher release rate than those prepared using non-ionic surfactants, Span 20 and Span 80, while those prepared from Tween showed higher release rate than formula prepared with Span. This indicates that lipophilicity and hydrophilicity of surfactant has a main role in release rates of piroxicam. Particle size of piroxicamniosomal vesicles formed by proniosome was determined by scanning electron microscopy. The encapsulation efficiency was evaluated by a specific high performance liquid chromatography method. Niosomes formed from using Spans and Tweens exhibited very high encapsulation efficiency. The results assured by Alsarra IA are very encouraging and he suggested that niosomes can act as promising carriers offering an alternative approach for transdermal delivery of piroxicam.

J Pharm Pharmacol.2004 Dec;56(12):1509-17.4 Development of a topical niosomal preparation of acetazolamide: preparation and evaluation.Aggarwal D1,Garg A,Kaur IP.Orally administered acetazolamide has a limited use in glaucoma due to the systemic side effects associated with its use. No topical formulation of acetazolamide is available, mainly because of it having a limited aqueous solubility and poor corneal permeation. To enhance the bioavailability of acetazolamide by the topical route and to improve the corneal permeability of the drug, niosomes of acetazolamide were prepared (employing span 60 and cholesterol) by different methods. Transmission electron microscopy (TEM) of the selected formulation was carried out to study the morphology. Niosomes were also prepared in the presence of dicetyl phosphate and stearylamine to obtain negatively and positively charged vesicles, respectively. It was found that the reverse-phase evaporation method (REV) gave the maximum drug entrapment efficiency (43.75%) as compared with ether injection (39.62%) and film hydration (31.43%) techniques. Drug entrapment efficiency varied with the charge and the percent entrapment efficiency for the REV method was 43.75, 51.23 and 36.26% for neutral, positively charged and negatively charged niosomes, respectively. Corneal permeability studies, however, showed that the percent permeation and the apparent permeability coefficient for the charged niosomes were less than for the neutral ones. A bioadhesiveniosomal formulation of acetazolamide was also prepared and compared with the positively charged formulation, considering that both of them would have a prolonged stay in the cul-de-sac because of their expected interactions with mucin. The formulations were also compared based on their intraocular pressure (IOP)-lowering capacity. The positively charged niosomes (REV2), although showing good corneal permeability and pharmacodynamics, were however found to be inappropriate in terms of the corneal cell toxicity. The bioadhesive coated formulation (REV1bio) compared well with REV2 and also showed a much lesser toxicity. Further, the IOP-lowering effect of the developed formulations was compared with that of a marketed formulation of dorzolamide 2%, a topical carbonic anhydrase inhibitor. The developed niosomal formulations of acetazolamide showed a comparable physiological effect (33% reduction of IOP in REV1bio and 37% reduction in dorzolamide) with a duration of up to 6 h (the duration being 3 h for dorzolamide). Results of the study done by Agarwal D.et.al indicate that it is possible to develop a safe (as indicated by corneal toxicity studies) and physiologically active topical niosomal formulation of acetazolamide relative in efficiency to the newer local carbonic anhydrase inhibitor, dorzolamide.Agarwal D.et.al showed that the developed formulations can form a cost effective treatment plan, which is especially important in the treatment of glaucoma, a chronic ailment affecting middle-aged to old patients.

Int J Pharm.2005 Dec 8;306(1-2):71-82. Epub 2005 Nov 2.5 Preparation and evaluation of reverse-phase evaporation and multilamellarniosomes as ophthalmic carriers of acetazolamide.Guinedi AS1,Mortada ND,Mansour S,Hathout RM.Guinedi AS.et.al.suggested that niosomes improve the low corneal penetration and bioavailability characteristics shown by conventional ophthalmic vehicles. Niosomes formed from Span 40 or Span 60 and cholesterol in the molar ratios of 7:4, 7:6 and 7:7 were prepared using reverse-phase evaporation and thin film hydration methods. The prepared systems were characterized for entrapment efficiency, size, shape and in vitro drug release. Stability studies were carried out to investigate the leaching of drug from niosomes during storage. The intraocular pressure (IOP) lowering activity of acetazolamide niosomal formulations in rabbits was measured using Shitz tonometer. Histological examination for the corneal tissues of rabbits receiving niosomal formulations was carried out for assessment of the ocular irritancy of niosomes. The results showed that the type of surfactant, cholesterol content and the method of preparation altered the entrapment efficiency and drug release rate from niosomes. Higher entrapment efficiency was obtained with multilamellarniosomes prepared from Span 60 and cholesterol in a 7:6 molar ratio. Niosomal formulations have shown a fairly high retention of acetazolamide inside the vesicles (approximately 75%) at a refrigerated temperature up to a period of 3 months. Each of the tested acetazolamide niosomes prepared by either method produced a significant decrease in IOP compared to the solution of free drug and plain niosomes. Multilamellar acetazolamide niosomes formulated with Span 60 and cholesterol in a 7:4 molar ratio were found to be the most effective and showed prolonged decrease in IOP. Histological examination of corneal tissues after instillation of niosomal formulation for 40 days showed slight irritation in the substantiapropria of the eye which is reversible and no major changes in tissues were observed.

Biol Pharm Bull.2014;37(4):541-51.6 Potential use of niosomal hydrogel as an ocular delivery system for atenolol.Abu Hashim II1,El-Dahan MS,Yusif RM,Abd-Elgawad AE,Arima H.Abu Hashim II.et.al.reported that niosomes improve the low corneal penetration and bioavailability characteristics for many drugs. The purpose of this study was to prepare and characterize an effective ocular niosomal hydrogel containing 0.5% (w/v) atenolol which is 1 adrenoceptor blocker for treatment of glaucoma. Thin film hydration method was used for the preparation of niosomes using Span 60 and cholesterol at different molar ratios. Niosomes were characterized using laser diffraction particle size analyzer, transmission electron microscopy, and differential scanning calorimetry. The results showed that higher entrapment efficiency (80.7%1.2) was obtained from niosomes prepared using Span 60/cholesterol at a 2 : 1 molar ratio. Stability study revealed that a fairly high retention of atenolol inside vesicles (83.1%2.35) up to a period of 3 months at 4C. Abu Hashim.et.al found that niosomal hydrogel formulation using carbopol 934P significantly exhibited sustained in vitro release of the drug compared with free drug solution and other polymeric hydrogels. The intraocular pressure (IOP) lowering activity of selected atenolol formulations was determined and compared with that of atenolol solution. It is worth noting that niosomal hydrogel formulation was found to show the most significant prolonged decrease in IOP, suggesting that niosomal hydrogel could be a promising delivery system for atenolol.Int J Pharm.2012 Feb 28;423(2):303-11. doi: 10.1016/j.ijpharm.2011.11.032. Epub 2011 Dec 2.7 Physicochemical properties and skin permeation of Span 60/Tween 60 niosomes of ellagic acid.Junyaprasert VB1,Singhsa P,Suksiriworapong J,Chantasart D.Ellagic acid (EA) is a potent antioxidant phytochemical substance which has limitation to use due to its poor biopharmaceutical properties, low solubility and low permeability. The aim of the present study was to develop niosomal formulations obtained from the mixture of Span 60 and Tween 60 that could encapsulate EA for dermal delivery. The EA-loaded niosomes were prepared with 1:0, 2:1, 1:1, 0:1 Span 60 and Tween 60, using polyethylene glycol 400 (PEG 400), propylene glycol (PG) or methanol (MeOH) as a solubilizer. The influence of formulations on vesicle size, entrapment efficiency and stability of EA-loaded niosomes was investigated. It was found that all ratios of surfactants could produce EA-loaded niosomes when using 15% (v/v) PG, 15% (v/v) PEG 400 or 20% (v/v) MeOH. The niosomes were spherical multilamellar vesicles showing the localization of EA in the vesicles. The vesicle sizes of the niosomes after extrusion were 124-752 nm with PI less than 0.4. The percentages of entrapment efficiency (% E.E.) of all EA-loaded niosomes varied between 1.35% and 26.75% while PEG 400 niosomes gave the highest % E.E. The most stable and highest entrapped formulation was 2:1 Span 60 and Tween 60 niosomes. Additionally, the in vitro skin permeation revealed that penetration of EA from the niosomes depended on vesicle size, the amount of EA entrapped and the added solubilizers which could act as a permeation enhancer. From skin distribution study, the EA-loaded niosomes showed more efficiency in the delivery of EA through human epidermis and dermis than EA solution. The experiment done by Junyaprasert VB et.al. showed that the Span 60 and Tween 60 niosomes may be a potential carrier for dermal delivery of EA.

Int J Pharm.2008 Aug 6;360(1-2):156-63. 8 Anti-inflammatory activity of gel containing novel elastic niosomes entrapped with diclofenacdiethylammonium.Manosroi A1,Jantrawut P,Manosroi J.The objective of the study done by Manosroi A.et.al was to develop a novel elastic bilayer vesicle entrapped with the non-steroidal anti-inflammatory drug (NSAID), diclofenacdiethylammonium (DCFD) for topical use. Eighteen bilayer vesicular formulations composing of DPPC or Tween 61 or Span 60 mixed with cholesterol (at 1:1, 3:7 and 1:1 molar ratios, respectively) and ethanol at 0-25% (v/v), by chloroform film method with sonication were developed. The elastic Tween 61 niosomes which gave no sedimentation, no layer separation, unchanged particle sizes (about 200 nm) were selected to entrap DCFD. The entrapment efficiency of the drug in the conventional and elastic Tween 61 niosomes was 65 and 93%, respectively. At least 87% of DCFD determined by HPLC remained in elastic Tween 61 niosomes when kept at 4, 27 and 45 degrees C for 3 months. The deformability index values of the elastic niosomes were 13.76 and 3.44 times higher than the conventional niosomes entrapped and not entrapped with the drug, respectively, indicating the higher flexibility of the elastic vesicle especially, when entrapped with the drug. Transdermal absorption through excised rat skin was performed by vertical Franz diffusion cell at 32+/-2 degrees C for 6h. Gel containing elastic niosomes exhibited fluxes of DCFD in the stratum corneum (SC), deeper skin layer (viable epidermis and dermis, VED) and receiver chamber at 191.27+/-9.52, 16.97+/-2.77 and 3.76+/-0.54 microg/(cm2 h), whereas the commercial emulgel, containing an equivalent DCFD, gave 60.84+/-13.63, 7.33+/-1.70 and 0.14+/-0.01 microg/(cm2 h), respectively. The in vivo anti-inflammatory activity was evaluated by ethyl phenylpropiolate (EPP)-induced rat ear edema (n=3). DCFD entrapped in the developed elastic niosomes and incorporated in gel gave the same ear edema inhibition percentages of 23.81% at 30 min, but 2 and 9 times more inhibition percentages at 45 and 60 min than the commercial emulgel, respectively. This result has not only demonstrated the enhancement of transdermal absorption through rat skin, but also the in vivo anti-inflammatory effect of DCFD when entrapped in the developed novel elastic Tween 61 niosomes, as well.Int J Pharm Investig.2012 Oct;2(4):201-7. doi: 10.4103/2230-973X.107002.9 Formulation and evaluation of Ketoconazole niosomal gel drug delivery system.Shirsand S1,Para M,Nagendrakumar D,Kanani K,Keerthy D.PURPOSE:Niosomes play an increasingly important role in drug delivery as they can reduce toxicity and modify pharmacokinetic and bio-availability. Topically applied niosomes can increase the residence time of drugs in the stratum corneum and epidermis, while reducing the systemic absorption of the drug. It can act as drug containing reservoirs and the modification of the vesicular compositions or surface properties can adjust the drug release rate and the affinity for the target site. Ketoconazole is a broad spectrum Imidazole derivative useful in the treatment of superficial and systemic fungal infections.MATERIALS AND METHODS:In order to improve the low skin penetration and to minimize the side effects associated with topical conventional drug administration, Ketoconazole niosomes were prepared by a thin film hydration method using different ratios of non-ionic surfactants (Span 40, 60 and Tween 60) along with cholesterol (CHO). The formulations were evaluated for size, shape, entrapment efficiency and in vitro drug release.RESULTS:Niosomes appeared spherical in shape and size range was found to be 4.86 1.24-7.38 3.64 m. The entrapment efficiency was found in the range of 55.14 2.29-78.63 0.91% and in vitro drug release in the range of 46.63 0.95-72.37 0.59% in 24 h. Ketoconazole niosomes formulated with Span 60 and CHO in the ratio of 1:0.2 were found to be promising and were incorporated into 1% Carbopol gel. The formulated gel was evaluated for various physicochemical parameters and antifungal activity. The in vitro drug release study was carried out using phosphate buffer saline pH 7.4 and was found to be 36.18 1.50% in 12 h.CONCLUSION: Shirshad.et.al concluded that gel formulation containing niosomes loaded with Ketoconazole showed prolonged action than formulations containing Ketoconazole in non-niosomal form and it can be developed successfully to improve the antifungal activity.

Drug Deliv.2010 Jul;17(5):282-7..10 Preparation and characterization of niosomes containing ribavirin for liver targeting.Hashim F1,El-Ridy M,Nasr M,Abdallah YThe objectives of Hashim F.et.al studies were to prepare ribavirin niosomes and evaluate the influence of niosomal encapsulation on drug liver targeting in rats. Ribavirin niosomes were prepared by the thin film hydration method using span 60, cholesterol, and dicetyl phosphate in molar ratios of (1:1:0), (4:2:0), (1:1:0.1), and (4:2:1). The prepared niosomes were characterized in vitro for vesicle size, drug entrapment, drug release profiles, and vesicular stability at refrigerator temperature. The results indicated that niosomes of the molar ratio (4:2:1) had a significantly (p < 0.05) higher entrapment percentage of ribavirin than the other molar ratios, moreover, they revealed sustained release characteristics as well as longer release pattern than other niosomal formulations. Accordingly, niosomes of molar ratio (4:2:1) was selected for in vivo liver targeting study. Separately, niosomal ribavirin dispersion and free ribavirin solution were administered as a single dose of 30 mg/kg by intraperitoneal injection into two groups of rats to compare the liver ribavirin concentration. The obtained results show that the niosomal formulation significantly increased ribavirin liver concentration (6-fold) in comparison with ribavirin-free solution. Based on the previous results, the use of niosomes as a drug delivery system for ribavirin has significant liver targeting properties, this is expected to improve the efficacy of low doses of ribavirin and minimize its toxic side-effects at higher doses.Pak J Pharm Sci.2013 Nov;26(6):1089-96.11 Design and characterization of ofloxacinniosomes.Ramalingam N1,Natesan G,Dhandayuthapani B,Perumal P,Balasundaram J,Natesan S.Niosomes are non ionic surfactant vesicles and potential surrogate for liposomes. The aim of the investigation done by Ramalingam N.et.al was to formulate and evaluate niosomes. The formulated ofloxacinniosomes were evaluated for their particle size, zeta potential, surface morphology, entrapment efficiency, in vitro drug release and in vivo pharmacokinetic studies. Niosomes of ofloxacin were prepared by thin film hydration technique using rotary flash evaporator. The formulated ofloxacinniosomes showed a vesicle size of 3.0-3.8 m and zeta potential of -9 to -13 mV. The in vitro release studies showed 98.79% of ofloxacin release in sustained manner following first order kinetics. The stability study confirmed the stability of Ofloxacinniosomes. Pharmacokinetics studies of ofloxacinniosomes made with Span 60 showed increased Cmax AUC, AUMC, t1/2 and MRT values compared to marketed intravenous ofloxacin product. The designed ofloxacinniosomes with span 60 showed good physicochemical properties, good stability, improved pharmacokinetic parameters, prolonged action and improved bioavailability than the commercially available conventional dosage form which might be a potential carrier system to improve the patient compliance and reduce the side effects.

Pharm Dev Technol.2013 May-Jun;18(3):667-72. 12 Effect of formulation compositions on niosomal preparations.Chaw CS1,Kim KY.

Chaw CS and Kim KY aimed to investigate the effects of molar ratio of cholesterol to Span 60 and stabilizers (Solutol HS 15 or dicetyl phosphate (DCP)) on the entrapment of methylene blue, a model hydrophilic drug. The niosomes were prepared by the film hydration method and characterized for drug entrapment efficiency (EE), vesicle size, zeta potential and thermal properties of niosomal membrane. It was found that niosomal vesicles possessed median diameter ranging from 0.35 to 1.85 m. The niosomes that were formulated with lower molar ratios of cholesterol to Span 60 of 0.33 and 0.50 produced significantly higher EE with both stabilizers when compared to cholesterol to Span 60 molar ratios of 1.0 and above (p < 0.05). The EE of niosomes stabilized with DCP was significantly higher (p < 0.05) than those prepared with Solutol HS 15 except at a molar ratio of cholesterol to Span 60 of 0.33. In conclusion, with low molar ratios of cholesterol to Span 60, more drugs could be entrapped within the niosomes regardless of the type of stabilizers. Furthermore, EE and median diameter of niosomes containing DCP were higher than those stabilized with Solutol HS 15.AAPS PharmSciTech.2013 Sep;14(3):1072-82. doi: 10.1208/s12249-013-9986-5. Epub 2013 Jul 2.13 Niosomal gel of lornoxicam for topical delivery: in vitro assessment and pharmacodynamic activity.Kumbhar D1,Wavikar P,Vavia P.Lornoxicam is a potent oxicam class of non steroidal anti-inflammatory agent, prescribed for mild to moderate pain and inflammation. Niosomal gel of lornoxicam was developed for topical application. Lornoxicamniosomes (Lor-Nio) were fabricated by thin film hydration technique. Bilayer composition of niosomal vesicles was optimized. Lor-Nio dispersion was characterized by DSC, XRD, and FT-IR. Morphological evaluation was performed by scanning electron microscopy (SEM). Lor-Nio dispersion was incorporated into a gel using 2% w/w Carbopol 980 NF. Rheological and texture properties of Lor-Nio gel formulation showed suitability of the gel for topical application. The developed formulation was evaluated for in vitro skin permeation and skin deposition studies, occlusivity test and skin irritation studies. Pharmacodynamic activity of the Lor-Nio gel was performed by carragenan-induced rat paw model. Optimized Lor-Nio comprised of Span 60 and cholesterol in a molar ratio of 3:1 with 30 Mdicetylpalmitate as a stabilizer. It had particle size of 1.125 0.212 m (d 90), with entrapment efficiency of 52.38 2.1%. DSC, XRD, and IR studies showed inclusion of Lor into niosomal vesicles. SEM studies showed spherical closed vesicular structure with particles in nanometer range. The in vitro skin permeation studies showed significant improvement in skin permeation and skin deposition for Lor-Nio gel (31.41 2.24 g/cm(2), 30.079 1.2 g/cm(2)) over plain lornoxicam gel (7.37 1.27 g/cm(2), 6.6 2.52 g/cm(2)).From the Kumbhar D.et.al studies they concluded that the Lor-Nio gel formulation showed enhanced anti-inflammatory activity by exhibiting mean edema inhibition (87.69 1.43%) which was significantly more than the plain lornoxicam gel (53.84 2.21%).

Int J Pharm.2013 Nov 18;456(2):446-58. doi: 10.1016/j.ijpharm.2013.08.040. Epub 2013 Aug 30.14 Formulation, characterization and pharmacokinetics of Morin hydrate niosomes prepared from various non-ionic surfactants.Waddad AY1,Abbad S,Yu F,Munyendo WL,Wang J,Lv H,Zhou J.Morin hydrate (MH), a bioflavonoid with antioxidant and anticancer activity as well as the ability to improve the bioavailability of other drugs on their concurrent use. Three differently optimized niosomal formulations using three different non-ionic surfactants (Span 60, Span 80 and Tween 60) were achieved by (L9 (3(4))) Taguchi orthogonal array (TOA).The analysis done by Wadded AY.et.al.revealed that Tween 60 Niosomes had the highest entrapment efficiency (93.4%) compared to other optimized Niosomal formulations (71-79%). In terms of MH remaining %, Tween 60 Niosomes were found to be the most stable (89%) at 4 C over one month compared to Span 60 (56%) and Span 80 (57%) Niosomes. The release pattern in all Niosomal formulations was found to follow the Weibull model and Tween 60 Niosomes had the highest release rate. The molecular modeling simulation explained the binding of MH to the human serum albumin (HSA) by hydrogen bonds during the in vitro release process. As for the bioavailability, the AUC0-8 showed 1.3-2.7 fold increase compared to the MH solution. Ex vivo images of the excised organs showed that MH could accumulate in brain which indicates that MH-Tween 60 Niosomes might be a possible candidate to deliver hydrophobic drugs and overcome the blood-brain barrier (BBB) penetration.

J Pharm Pharm Sci.2012;15(1):184-96.15 Development and characterization of niosomal formulations of doxorubicin aimed at brain targeting.Bragagni M1,Mennini N,Ghelardini C,Mura PPURPOSE:The aim of the present work of Bragagni M.et.al was the development and characterization of a niosomal formulation functionalized with the glucose-derivative N-palmitoylglucosamine (NPG) to obtain a potential brain targeted delivery system for the anticancer agent doxorubicin.METHODS:Five different methods have been examined for vesicle preparation. Light scattering and transmission electron microscopy were used for vesicle characterization, in terms of mean size, homogeneity and Zeta potential, and selection of the best composition and preparation conditions for developing NPG-functionalized niosomes. Drug entrapment efficiency was determined after separation of loaded from unloaded drug by size exclusion chromatography or dialysis. Preliminary in vivo studies were performed on rats, injected i.v. with 12 mg/kg of doxorubicin as commercial solution (Ebewe, 2 mg/mL) or NPG-niosomal formulation. Drug amounts in the blood and in the major organs of the animals, sacrificed 60 min post injection, were determined by HPLC.RESULTS:The selected formulation consisted in Span:cholesterol:Solulan:NPG (50:40:10:10 mol ratio) vesicles obtained by thin-layer evaporation, leading to homogeneous vesicles of less than 200 nm diameter. This formulation was used for preparation of NPG-niosomes loaded with doxorubicin (mean size 1614 nm, encapsulation efficacy 57.81.8%). No significant changes (P>0.05) in vesicle dimensions, Zeta potential or entrapment efficiency were observed after six months storage at room temperature, indicative of good stability. I.v. administration to rats of the NPG-niosomal formulation allowed for reducing drug accumulation in the heart and keeping it longer in the blood circulation with respect to the commercial formulation. Moreover, a doxorubicin brain concentration of 2.90.4 g/g was achieved after 60 min, while the commercial solution yielded undetectable drug brain concentrations (