Analytical evaluation of plant constituents

Spectrophptometric methods:

i) UV- Ultra violet /visible spectroscopy ii) IR-Infra Red spectroscopy iii) Fluorescence analysis iv) NMR-nuclear magnetic resonance spectroscopy v) MS-Mass spectroscopy vi) X-ray diffraction vii) RIA-radio immuno assay

viii) Chromatographic techniques:

a)TLC-Thin layer chromatography b)HPTLC-High performance thin layer chromatography c)HPLC-High performance/pressure liquid chromatography d)GC-Gas chromatography e)CC-column chromatography f)Gel permeation chromatography g)Affinity chromatography

Analytical evaluation

Spectrophptometric methods:

i) UV- Ultra violet /visible spectroscopy Ultra violet –visible absorption techniques encompass analytical methods based up on measurement of light absorption by substances in wave length region from 190 to 900 nm 190-380 nm UV region. 380-900 nm visible region. Applications :we can analyze variety of pharmaceutical

phytoconstituents like Lobeline-244 nm, Morphine-286 nm Antharaquinone 505 nm .

ii)IR-Infra Red spectroscopy -12,500-400 cm-1, Mid IR-

4000-400 cm-1 Far IR-400-20cm- ometer can be divided in to single and double beam and Fourier transform spectrophotometer(FTIR) Applications :Identification of drugs, polymorphs Raw

materials,excipients.

iii) Fluorescence analysis cific range of wave length, and many of them re- -emission of

absorbed light losts only when substance receiving exiting rays, and called as fluorescence.

iv) NMR-nuclear magnetic resonance spectroscopy

sample and it occurs at different frequencies for nuclei with chemically different environment. Applications NMR is imp tool in elucidation of molecular structure It is applicable in identification of impurities. It reveals

position of protons in a complex

v) MS-Mass spectroscopy h the electron ionisation,subsequent fragmentation of molecules, determination of the mass to charge ratio (m/e).and relative abundances of ions

drug constituents.

vi) X-ray diffraction: Many compounds are capable of crystallising in more than one type of crystal lattice at a particular temperature and pressure, since the rate of phase transformation of a metastable polymorph to the

stable one can be quite slow.Polymorphs plays a very imp role in pharmaceutical science

vii) RIA-radio immuno assay labeled form of the same drug. The label may be particular radio-isotope, active-enzyme or a C14 and iodine

I125 commonly used isotopes in RIA.RIA is method of choice for identification of cardiac glycoside, insulin.

viii) Chromatographic techniques:

a)TLC-Thin layer chromatography

to analyse Alkaloids, Glycosides like all bio- y,nature,of

determination of natural products

Advantages :simple in operation and rapid.

Thin layer chromatography(TLC), has become increasingly popular for both qualitative and quantitative evaluation of drugs. • Rf values refers to the ration of distance travelled by the solute to the distance moved

by the solvent on a thin layer adsorbent

b)HPTLC-High performance thin layer chromatography:

-Gel with very small particle size used as

-HPTLC plates are produced from 4-achieved in about 4 minutes.

c) HPLC-High performance/pressure liquid chromatography to those methods in which the separation takes place with packed column.(stationary) A liquid mobile phase

less) flow rate of mobile phase is (100μl /min) Advantages : most versatile ,safest.

Uses :quality control of drugs like morhine,emetine,steroids

d) GLC-Gas liquid chromatography stationary phase. Principle :GLC works on partitioning Carrier gas used as mobile phase (Nitrogen, Helium) A film of a liquid spread over an inert solid. Acts as stationary phase. GLC applied for i.Assay of impurities ii.Examination of volatile oils plant alkaloids.

e)CC-column chromatography iquid passes over

chromatography is oldest and still practiced to day for extraction process.

f)Gel permeation chromatography -exclusion chromatography.seperation occurs not on the basis of

adsorption /partition ,but on the effective size of solutes present in solution for the separation purpose.

g)Affinity chromatography protiens,enzymes,ant

attached to a porous stationary phase and placed in a column, when mixture containing the other complement of adsorbent passed through stationary phase.