Sodium Dodecyl Sulfate-Linear Polyacrylamide-Bonded Capillary Electrophoresis for the Molecular Weight Determination of Proteins

Abstract

Sodium dodecyl sulfate (SDS)-linear polyacrylamide-bonded capillary electrophoresis has been developed for the separation and molecular weight determination of proteins. Vinyl groups were introduced to silanol groups on the inner wall of fused silica capillaries by a Grignard reaction, followed by reaction of the vinyl group with acrylamide, resulted in a sieving medium of linear polyacrylamide attached through hydrolytically stable Si-C linkages. The durability of the developed capillary were improved as compared with the SDS-linear polyacrylamide-filled capillary using a conventional fused silica capillary. An excellent linear relationship existed between the mobility and the logarithm of the molecular weight of proteins (r²>0.998). The relative standard deviation of migration times was below 1.0% (n=10).