Synthesis of Biocompatible Polymers with Aspirin-Moieties for Aspirin Delivery

Abstract

Polyacrylate and polyhydroxylate polymers with aspirin moieties were prepared. The acrylate polymers were obtained by the synthesis and poly merization of several new monomers; β-(acetylsalicylyloxy)ethy methacrylate, β-(acetylsalicylyloxy)propyl methacrylate, β-(acetylsalicylyloxy)ethy acrylate, β-hydroxy-γ-(acetylsalicylyloxy)ethyl methacrylate and β-hydroxy-γ-(acetylsali cylyloxy)propyl methacrylate. The second series of biocompatible polymers with aspirin moieties was prepared by reacting the hydroxyl group of poly(vinyl alcohol) and poly(allyl alcohol) with 1-(acetylsalicylyl)benzotriazole. Both the homogeneous and heterogeneous hydrolysis of eight biocompatible polymers and copolymer with aspirin moieties were investigated in acidic or alkaline medium at 37 ° C or 60 °C, respectively. The main hydrolysis product was aspi rin with minor amounts of salicylic acid. The release rates of aspirin and sali cylic acid were related to the hydrolysis temperature, and the length of side chain. The release rate of aspirin and salicylic acid from poly[1-(acetylsalicylyl oxy)ethyl methacrylate-co-methacrylic acid] is markedly dependent on polymer composition and the pH value of hydrolysis medium.