Chromatography & Band Broadening

This ppt explained the general desctiption of Chromatography techniques and types of chromatography technique. It also explained the process of Band Broadening .

1. CHROMATOGRAPHY & BAND BROADENING Submitted By, M. Pratheep , ICE – 4 th Year , SCE , Trichy.

2. SEPERATION METHODS General description of Chromatography. Band broadening and optimization of column performance.

3. CHROMATOGRAPHY : Chromatography is a physical process where the Components (solutes) of a sample mixture are Separated as a result of their differential distribution between stationary phase and mobile phase.

4. PRINCIPLE: Chromatography is usually based on the principle of Partition of solute between two phases (Mobile phase and Stationary phase). The Mobile phase usually refers to the mixture of the substances to be separated dissolved in a liquid or gas. The Stationary phase is a porous solid matrix through which the sample contained in the mobile phase percolates.

5. HISTORY : Russian botanist Mikhail Tswett (referred to as Father of Chromatography) is credited for the development of chromatography. He used this technique to separate various plant pigments such as chlorophyll and xanthophyll packed with finely divided Calcium Carbonate. The separated species appeared as coloured bands on the column which leads to the name “Chromatography” In Greek Chrome means ‘Colour’ and Graphy means ‘Writing’.

6. SPECIALITY OF CHROMATOGRAPHY : It can separate complex mixture with great precision. Very similar components such as proteins that may only vary by a single amino acid can be separated efficiently. It can purify any soluble are volatile substances. It can be used to separate delicate products.

7. TYPES OF CHROMATOGRAPHY : CHROMATOGRAPHY Gas Liquid Chromatography Chromatography Gas-Solid Liquid-Solid Gas-Liquid Liquid-Liquid Ion exchange chromatography

8. PAPER CHROMATOGRAPHY :

9. APPLICATIONS OF CHROMATOGRAPHY : The chromatographic technique is used for the separation of amino acids , proteins & carbohydrates.. It is also used for the analysis of drugs, hormones, vitamins. Helpful for the qualitative and quantitative analysis of complex mixtures. The technique is also useful for the determination of molecular weight of proteins.

10. BAND BROADENING : Band broadening is a general term used to describe the overall dispersion or widening of a sample peak as it passes through a separation system. Band broadening in a chromatography is a result of several effects. These includes diffusion of solutes between the mobile phase and stationary phases, etc..

11. BAND BROADENING :

12. There are four general contributions to broadening within chromatographic columns. There are known as ; Longitudinal diffusion. Eddy diffusion. Mass Transport broadening in the stationary phase. Mass Transport broadening in the mobile phase. COLUMN EFFICIENCY: The sharpness of the peak is an indication of the efficiency of the column.

13. METHODS OF REDUCING BAND BROADENING : Small packing diameter (of stationary phase). Small column diameter. Optimum flowrate of mobile phase. Optimum temperature. Variation in solvent composition. For liquid stationary phase - thickness of the layer should be minimized.

14. !...THANK YOU…! Email Id : [email protected]