Principles of Biochemistry (2+1)

5.3.2.2.2.3 Size-exclusion chromatography (gel filtration)

5.3.2.2.2.3 Size exclusion (Gel filtration) chromatography

This chromatography separates larger proteins from small ones, since the larger molecules travel faster through the cross-linked polymer in the chromatography column. The large proteins do not fit into the pores of the polymer whereas smaller proteins do, and take longer to travel through the chromatography column, via their less direct route.

Eluate is collected in a series of tubes separating proteins based on elution time. Gel filtration is a useful tool for concentrating a protein sample, since the target protein is collected in a smaller elution volume than was initially added to the column. Such techniques might be used during large scale protein production because of their cost-effectiveness.