Synthesis, Characterization and Hydrolytic Behavior Study of Vinyl Ester Type Ibuprofen Polymeric Prodrugs

In this present research work, vinyl ester type polymeric systems linked to ibuprofen were synthesized and evaluated as materials for drug delivery systems. Vinyl 2-(4-isobutylphenyl)propionate (VIP), as a new vinyl ester type derivative of ibuprofen was synthesized by reaction of ibuprofen and vinyl acetate in the presence of mercuric acetate as a catalyst. The resultant compound was then copolymerized with 2-hydroxyethyl methacrylate (HEMA) or methyl methacrylate (MMA) monomers by free radical polymerization method. The structure and molecular weight of all the compounds was characterized by FT-IR, 1HNMR, 13CNMR, elemental analysis and gel permeation chromatography techniques. The hydrolysis of the drug-polymer conjugates was carried out in cellophane membrane dialysis bags containing aqueous buffered solutions (pH 1, 7.4 and 10) at 37 oC for 48 h. The release profiles indicated that the hydrolytic behavior of the polymeric prodrugs is strongly based on the polymer hydrophilicity and the pH value of the hydrolysis solution.