Gel Filtration Chromatography

Gel filtration chromatography : In this technique of chromatography, separation of molecules is accomplished, on the base of their size, shape and molecular weight. Gel filtration chromatography is also known as molecular sieve or molecular exclusion chromatography.

In this type of chromatography a packed column consists of a sponge like gel beads (usually cross-linked polysaccharides) containing pores.

The pores on the surface of gel allows small molecules to penetrate inside, whereas larger molecules are left outside and eluted with a buffer, hence the name exclusion chromatography.

The gels are commercially available in different types (e.g. Sephadex G-25, G-50, G-250, etc.) depending upon the pore size and hence, suitable for different set of molecules

depending on their molecular weight.

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