3. Chromatographic
techniques
Thin layer chromatography (TLC / HPTLC)
• Identification and determination of herbal extracts
• Identification and determination of fixed and volatile oils.
• Analysis of a wide variety of organic and inorganic
materials
• TLC has been utilized for the determinationof some
steroids
• TLC plays a crucial role in the early stage of drug
development when information about the impurities and
degradation products in drug substance and drug product
is inadequate.
5. Chromatographic
techniques
High Performance Liquid Chromatography (HPLC)
• Used in separating the complex
mixture of molecules encountered
in chemical and biological
systems,
• The principal method in USP
• To separate and analyze complex
mixtures or solutions which
include liquids and solids of both
organic and inorganic origins
6. Chromatographic
techniques
Gas Chromatography (GC)
• Powerful separation technique
for detection of volatile organic
compounds.
• Used for assay of drugs
• Determination of residual solvents
• Important tool for analysis of
impurities of pharmaceuticals.
Agilent 8890 GC system
7. Spectroscopic
techniques
Spectrophotometry
• Based on natural UV absorption and chemical reactions
• Spectrophotometry is the quantitative measurement of the
absorption, reflection or transmission properties of a
material as a function of wavelength.
• The advantages of these methods are low time and labor
consumption.
8. Spectroscopic
techniques
Spectrophotometry
• The use of UV–Vis spectrophotometry especially applied in
the
analysis of pharmaceutical dosage form and for the assay
of bulk materials.
• The colorimetric methods are usually based on the
following aspects:
1. Complex-formation reaction.
2. Oxidation-reduction process.
3. A catalytic Spectrophotometer Shimadzu UV-19001
9. Spectroscopic
techniques
Fluorescence spectroscopy
It uses a beam of light that excites the
electrons in molecules of certain compounds, and
causesthem to emit light.
That light is directed towards a filter and onto a detector for
measurement and identification of the molecule or changes in
the
molecule.
Fluorescence spectroscopy analyzes fluorescence from a
10. Spectroscopic
techniques
Fluorescence spectroscopy
The applications of this technique are limited and it offers
quantitative estimations of those compounds like benzene
and fused benzene ring systems.
Inorganic metals can also be analyzed by the ability of them
to form complexes with the ligands.
11. Spectroscopic
techniques
Fluorescence spectroscopy
It finds usesin the analysis of foods for
vitamin content, since vitamins like riboflavin,
niacin, etc., exhibitfluorescence.
Only limited compounds show the fluorescence hence
this technique is relatively free of any
interference and is very
sensitive
12. Spectroscopic
techniques
Fourier Transform Infrared spectroscopy (FTIR)
It is preferred method of infrared spectroscopy.
In infrared spectroscopy, IR radiation is passed through a
sample. Some of the infrared radiation is absorbed by the
sample and some of it is passed through (transmitted).
The resulting spectrum representsthe molecular absorption
and transmission, creating a molecular fingerprint of the
sample.
13. Spectroscopic
techniques
Fourier Transform Infrared spectroscopy (FTIR)
Like a fingerprint no two unique molecular structures produce
the
same infrared spectrum.
FTIR is used for identifying organic compounds, both
quantitatively and qualitatively.
In quantitative research, FTIR is used to figure out an analyte
concentration in a sample. In qualitative research, FTIR is
used for identifying the functional groups that make up a
14. Spectroscopic
techniques
Atomic Absorption Spectroscopy (AAS)
This is the most widely used technique for the
quantitative
determination of metals at trace levels (0.1 to 100ppm),
which present in various materials.
The sample is vaporizedby aspiration of solution into a flame or
evaporation from electrically heated surface. At this condition
where the individual atoms co-exist, a beam of light is passed
through them.
15. Spectroscopic
techniques
Atomic Absorption Spectroscopy (AAS)
The atoms will absorb in the visible and ultraviolet region
resulting in changes in electronic structure (excited state). So,
the resultant light beam coming out of the sample will be
missing the light in the corresponding wave length, which is a
measure of the characteristics of the sample.
16. Spectroscopic
techniques
Plasma Emission Spectroscopy
Mostly referred as Inductively Coupled Plasma (ICP) Emission
Spectroscopy. Atoms and ions present in the sample are excited
in high temperature gas plasma. Since the plasma provides
very high temperature and hence the energy, almost all the
atoms present in the sample can be excited with this technique
ending up with high efficiency (a hotter source increases both
atomization efficiency and excitation efficiency).
17. Spectroscopic
techniques
Plasma Emission Spectroscopy
Thus, the emissions from the atoms would be more intense and
even very small concentrations of metals/metal ions can be
detected and accurately measured.
Agilent 5900 ICP-OES with auto sampler
and microwave
19. Spectroscopic
techniques
Electrochemical analysis
There are severaltechniquesunder this title like
Potentiometry, Amperometry, Conductometry,
Voltametry, etc.,
Potentiometry
We use a potentiometer to determine the difference between
the potential of two electrodes. The potential
of one electrode—the
working or indicator electrode—responds to the analyte’s
activity, and the other electrode—the counter or reference
21. Spectroscopic
techniques
Electrochemical analysis
Applications
• Determination of chloride
• It is usedfor the analysis of cyanide,
ammoniaetc., in water or wastewater.
• It is used in agriculture for the detection of different elements
in soils, fertilizers etc.
• It is used in detergent manufacturing, food processing etc.
22. Spectroscopic
techniques
Electrochemical analysis
Ion selective electrode (ISE) analysis is an electroanalytical
technique that uses an electrochemical cell consisting of two
electrodes and a sample solution (electrolyte). The electrodes
contain an ion permissible membrane that is selective of the
ion that passes through it. This membrane separates the
sample from the electrode internals. An internal reference
electrode present within the ISE is made of silver wire with
silver chloride coating and is fixed in a concentrated
potassium chloride solution saturated with silver chloride.
Example : Determination of
23. Spectroscopic
techniques
Thermal analysis
The technique of thermal analysis actually comprises of a
series of methods, which detect the changes in the physical
and mechanical properties of the given substance by the
application of heat or thermal energy
