pharmceutical analysis m.pharm advanced pharmaceutical analysis

1. KARNATAKA COLLEGE OF PHARMACY
Seminar topic: UV-VISIBLE METHOD
By: KAVANA BB
1ST SEM M Pharm
Subject : APA
DEPARTMENT OF PHARMACEUTIAL ANALYS SUBMITTED TO:DR.C .SREEDHAR
HOD AND PROFESOR
DEPARTMENT OF PHARMACEUTICAL ANALYSIS
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2. Titration
• Titration is a common laboratory method of quantitative chemical analysis
to determine the concentration of an identified analyte.
• The purpose of the titration is the detection of the equivalence point, the
point at which chemically equivalent amounts of the reactants have been
mixed.
• Titration can analyse purity and content.
• It supports the preparation of pharmaceutical
products and the manufacturing of biodiesel fuel
from vegetable oil.
• It is used extensively in product development
and quality control.
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3. • Titration are done by three methods :
1. Using indicator
2. By using spectrophotometer
3. By using ion selected electron
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4. PHOTOMETERIC TITRATION
• This method is also known as uv-visible method.
• Photometric titrations are similar to the normal visual
titration but following course of photometric titration occurs
with the aid of a uv-visible detectors, rather than the naked
eye.
• Here absorbance is used to determine the end point.
• These titration are based on Beer’s law. Coloured compound
will absorb radiation.
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5. Instrumentation
• Photometric titrations can be carried out using a spectrophotometer that has
been modified to permit the insertion of a titration vessel in the light path.
• However, it is much more common nowadays for photometric titrations to be
carried out using automated apparatus consisting of a spectrophotometer or
photometer, a titration vessel and stirrer, an automated burette, and
software to control the titration and present the results.
• The titration vessels used are often cylindrical, with volumes of up to
100 ml.
• The titrant is incrementally added to the stirred vessel through the top and
absorption readings taken after each titrant addition.
• Movements of the titration vessel during titrations must be avoided as
inaccuracies will result due to deviations from Beer's Law.
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7. Photometric titration curve
A photometric titration curve is a plot
of absorbance, corrected for volume
changes, as a function of the
volume of titrant.
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8. (a) Here titrand will absorb radiation, titrant and
product will not absorb
example: EDTA and ferric ions
ferric ions salicylic acid= ferric salicylate
(highly colored)
as adding EDTA ; Fe-EDTA COMPLE is formed
(colorless) ,hence the absorbance
at a particular point the complex complete is
formed then it is constant.
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9. (b) Here titrant will absorbs but
titrand and product will not.
• Example: AsCl3 with
KBr+KBrO3(brominating mixture)
• Absorbance increase when
brominating mixture is added
excess and after complete
consumption of AsCl3.
Volume of titrant
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10. • Here product will absorb radiation but
titrant and titrand will not.
• Example: EDTA and CuSO4 .
• As the product forms absorbance
increases at end point complete
consumption of cuso4 basobance will
b constant. Volume of titrant
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11. • Here the titrand and titrant absorbs
radiation but product will not
• Example: liq. bromine and red dye.
• As the product is formed absorbance
decreases and after complete
formation of product and excess
addition of titrant the absorbance
increases.
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13. Thank you
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