Adsorptions of Va rious Protein Molecules onto Polymer Microspheres Having Different Surface Hydrophilicity

Abstract

Adsorptions of proteins (bovine pancreas trypsin, bovine serum albumin, and human rglobulin)as high-molecules onto various microspheres of homopolymer and styrene-2-hydroxyethyl methacrylate copolymer (P(S-HEMA)) were investigated in comparison with that of an emulsifier (sodium dodecylbenzenesulfonate) as a low-molecule onto them. All polymer microspheres were prepared by emulsifier-free emulsion polymerization technique. Plots of the maximum amount of the emulsifier adsorbed versus those of the proteins onto polyme r microspheres gave straight lines in the adsorption onto homopolymer, whereas no straight lines were obtained in the adsorption onto P(S-HEMA). These results may be attributable to the, surfaces of P(S-HEMA) microspheres having a phase separated structure which consists of both hydrophobic and hydrophilic parts.