DEVELOPMENT OF CHITOSAN POLYETHYLENE VINYL-ACETATE CO-MATRIX - CONTROLLED-RELEASE OF ASPIRIN-HEPARIN FOR PREVENTING CARDIOVASCULAR THROMBOSIS/

Aspirin and heparin were embedded in chitosan/polyethylene vinyl aceta te co-matrix to develop a prolonged release form. The in vitro release profiles of these drugs from the co-matrix system were monitored in T ris HCl buffer pH 7.4, using a UV spectrophotometer. The amount of dru g release was initially much higher, followed by a constant slow relea se profile for a prolonged period. The initial burst release was subst antially modified with styrenebutadiene coatings. From scanning electr on microscopy studies it appears that the drugs diffuse out slowly to the dissolution medium through the micropores of the co-matrix. The re leased aspirin-heparin from the co-matrix system had shown their antip latelet and anticoagulant functions. The results propose the possibili ty of delivering drug combinations, having synergestic effects for the rapeutic applications. (C) 1997 Elsevier Science Limited. All rights r eserved.