Applications of Spectrophotometry .pptx

This presentation explores the diverse applications of spectrophotometry across the pharmaceutical, clinical, environmental, and research domains. 🌈
It covers how UV-Visible, IR, and Atomic Absorption Spectrophotometry are used for quantitative and qualitative analysis, drug assay, enzyme kinetics, pollutant detection, and food quality assessment.

The slides also highlight the principle, instrumentation, and working mechanism of spectrophotometers, providing a comprehensive understanding of how light absorption is utilized for precise and reliable measurements.

Whether you’re a student, researcher, or healthcare professional, this presentation will deepen your knowledge of how spectrophotometry contributes to analytical chemistry, pharmaceutical formulation, and quality control.

#Spectrophotometry #AnalyticalChemistry #Pharmacy #PharmaceuticalAnalysis #UVVisible #IRSpectroscopy #QualityControl #SlideShare

1. Spectroscopy & its applications Lokesh Patil 7 th sem B.pharm

2. Introduction "Unveiling the Invisible: The Power of Spectroscopy" 01

3. W hat is Spectroscopy…? It is branch of science that deals with interaction of matter with light or elctromagnetic radiation .

4. Less time consuming Very small amount of sample is required Cost effective in the long run Advantages of spectroscopy

5. Sectrophotometric titrations "Precision in Every Drop: Advancing Science with Spectrophotometric Titrations" 02

6. Spectrophotometric titrations Those titrations in which absorbance of the solution is used to determine the end point are called photometric titrations. The method is based on the fact that the absorbance of the solution is directly proportional to the concentration.

7. 1. Only the analyte absorbs….. If the analyte is the absorber while the titrant do not absorb , then the absorbance decreases during the titration and remain constant after the end point is reached

8. 2. Only the titrant absorbs….. If the titrant is capable to absorb then the absorbance initially remains constant but increases once the end point is reached as excess titrant is added.

9. 3. Only the product absorbs….. When the products are capable to absorb the radiations while the analyte and titrant cannot absorb . Thus the titrant is added to the analyte so the product formed absorbs the radiations.

10. 4. Analyte and titrant absorb…. When the titrant and analyte are capable to absorb and the products cannot …. Initially absorbance decreases as analyte diminishes and after the equivalence point, again the absorbance increases due to presence of excess titrant .

11. Single component analysis 03

12. Single component analysis Single component pharmaceutical assays can be determined using single point standardization which involves measuring the absorbance spectrum of standard solution of the reference sample and sample solution Standard absorptivity method Calibration graph Single or double point standardization

13. 1. Standard absorptivity value The concentration of the unknown compound can be determined by using standard absorptivity value and the measured absorbance. Mainly used for stable substances – broad absorption bands. This method is used when the substance is expensive or difficult to obtain

14. 1. Standard absorptivity value

15. 2. Calibration graph method The absorbances of a number of standard solutions of the reference substance at the concentration of the sample solutions are measured and a calibration graph is drawn.

16. 3. Single or double point standardization This method involves the measurement of the absorbance of sample solution of the reference substance. The concentration of substance in the sample is measured from the proportional relationship between the absorbance and concentration.

17. 3. Single or double point standardization

18. Multi component analysis 04

19. Multi component analysis If sample has more than one drug (analyte) and all of them absorb at same wavelength ( λ max ) then multiple component analysis is required. If the sample carry any excipients, impurities or decomposition product which absorb at ( λ max ) of drug then multiple component analysis is required.

20. Multi component analysis Simultaneous equation method ( Vierordt’s method) Difference spectrophotometry Derivative spectrophotometry Absorbance ratio method Geometric correction method Absorption factor method Area under curve method

21. 1. Simultaneous equation method If a sample contains 2 absorbing drugs (X & Y) each of which absorbs at the λ max of the other, it may be possible to determine both the frugs by the techniques of simultaneous equation

22. 1. Simultaneous equation method Information required is….

23. 1. Simultaneous equation method Formula for calculation of drug concentration

24. 2. Difference spectrophotometry If sample has interfering substances ( impurities, decomposition products or other drug ) then the selectivity and accuracy of method can be improved by this technique. In this method the measured value is the difference in absorbance ( dA ) between the two equimolar solutions of the analyte in different chemical forms , which exhibit different wavelengths.

25. 2. Difference spectrophotometry Eg. Solution of Phenylephrine in 0.1M HCL (pH 1) and in 0.1M NaOH (pH 13)

26. 3. Chemical derivatization These are known as indirect spectrophotometric assay. Sample (analyte) is converted into its coloured derivative using some reagent. This derivative have longer ( λ max ) and higher absorptivity value. Why chemical derivatization is required….? If the analyte do not have strong chromophore. If interfering substances are present To improve selectivity of assay To reduce cost

27. 3. Chemical derivatization Methods of chemical derivatization- Colourimetric estimation by oxidation Colourimetric estimation by complexation Colourimetric estimation by condensation reaction

28. i . Colourimetric titration by oxidation Eg. Ephedrine on oxidation produces Benzaldehyde. Benzaldehyde absorbs strongly at 240 nm.