Adsorption of enzymes onto submicron-sized temperature-sensitive composite polymer particles and its activity

Temperature-sensitive composite polymer particles were prepared by seeded emulsion copolymerization of dimethylaminoethyl methacrylate and ethylene glycol dimethacrylate with 0.14-mu m-sized polystyrene seed particles. Its reliability as a carrier for biomolecules was evaluated by measuring the enzymatic activity of trypsin adsorbed on the composite particle at a temperature above the lower critical solution temperature (LCST). Conformation of trypsin desorbed from the particle surface by lowering the temperature to below the LCST was examined with circular dichroism spectroscopy and compared with the native one. Both results indicate that enzymatic activity of the trypsin retained during the adsorption/desorption measurement. (C) 1999 Elsevier Science B.V. All rights reserved.