Preparation and characterization of bioadhesive grafted starch copolymers as platforms for controlled drug delivery

Co-60-gamma-radiation and ceric ammonium nitrate (CAN) redox-induced graft polymerization of acrylic monomers (acrylonitrile, acrylic acid, and methyl acrylate) to starch was performed to produce drug-delivery systems. The grafted starches obtained mainly by redox-induced polymerization were characterized by chemical and physicochemical methods, and the nature and size of the polyacrylic moiety grafted to the starch were determined. Although the choice of grafting method depended in part on the particular monomer, only copolymers obtained by gamma radiation proved to be satisfactory drug delivery systems. Changes of parameters in the gamma radiation-induced polymerization, such as radiation times and changes in the amount of starch and/or acrylic monomers, were tested in terms of the release rate of model drug compounds. (C) 2002 Wiley Periodicals, Inc.