Thermally responsive polymer as a sieving matrix of proteins in capillary gel electrophoresis

Abstract

A thermally responsive polymer, termed as P(IPAAm-AM-BisAM), was prepared by the copolymerization of N-isopropyl acrylamide, acrylamide, and N,N′-methylenebisacrylamide. At room temperature this polymer was dissolved in water to form a low viscous solution so that it could be loaded in a capillary easily. When a high voltage was applied on the capillary, the polymer was stimulated by the Joule heat and transferred from a liquid state into a solid state, acting as a sieving matrix for the separation of proteins according to their molecular weights. The logarithm values of the molecular weights of the proteins correlated linearly with the migration times. This capillary gel electrophoresis of proteins was carried out using a conventional instrument. Using such a copolymer, we can easily realize high-speed, high-efficiency and reproducible capillary gel electrophoresis for proteins without any instrumental rebuilding or investment.