Size-Exclusion Chromatography for Purification of Biomolecules
Size-exclusion chromatography (SEC) is a popular method to separate biomolecules based on their size. Primarily, it is applied to the separation of biopolymers such as proteins and nucleic acids, i.e. water-soluble polymers. This system is also called gel filtration, typically with beads of dextran or agarose serving as gel matrix. Smaller molecules pass significantly slower through the column than larger molecules. Not to be mixed up with gel electrophoresis, there are big differences in terms of the separation principle. SEC does not require electric current and the sieving effect will not separate small molecules first.