CHARACTERIZATION AND PERFORMANCE OF A NEUTRAL HYDROPHILIC COATING FORTHE CAPILLARY ELECTROPHORETIC SEPARATION OF BIOPOLYMERS

Polyvinylmethylsiloxanediol (50% vinyl) was synthesized and combined w ith a cross-linker for static coating onto fused-silica columns. After cross-linking and binding to the surface, linear polyacrylamide was g rafted to the double bonds of the siloxanediol; subsequently, this lin ear polymer matrix was cross-linked with formaldehyde. The grafted neu tral polymeric layer provided suppression of electroosmotic flow and m inimized adsorption. This combination yielded successful open tube and polymer network separations of proteins, peptides and DNA molecules. Very high efficiencies (ca. 1 . 10(6) plates/m) were achieved for open tube protein separations, and hundreds of consecutive runs were perfo rmed with minimal change in migration times.