What are the different molecular sieve effects in gel filtration chromatography and gel electrophoresis?

Gel filtration chromatography is also called molecular sieve chromatography and exclusion chromatography. It is the use of the molecular sieve action of a gel with a network structure, and separation is performed according to the molecular size of the substance to be separated. The fillers in the column are inert porous network materials, mostly crosslinked glycans (such as dextran or agarose). Small molecules can enter the interior of the column and travel longer distances. However, the macromolecular material is excluded from the outside and the down path is short. When a mixed solution passes through the gel filtration chromatography column, the substances in the solution are separated by different molecular weight sieves.

    In polyacrylamide gel electrophoresis (PAGE), the mobility of a protein depends on the net charge it carries and the size and shape of the molecule. After entering the separation gel, due to the molecular sieve action of polyacrylamide, small molecules of the protein can easily pass through the gel pore size, the resistance is small, and the migration speed is fast; the large-molecule protein is lagging behind due to large resistance, so that the protein is in the electrophoresis process. It will be separated according to the size of its respective molecular weight. The whole plastic sheet is equivalent to a molecular sieve.