Volume 6

January-March 2014

Formulation and in-vitro evaluation of vinyl ester type polymeric prodrugs of naproxen as drug delivery systems

Mirzaagha Babazadeh

Abstract:
This present research work describes synthesis and in-vitro evaluation of a serious of vinyl ester type polymeric systems linked to naproxen as materials for drug delivery. First, naproxen reacted with vinyl acetate in the presence of catalyst to obtain vinyl ester derivative of naproxen. The resulted material was then copolymerized with 2-hydroxyethyl methacrylate and methyl methacrylate by utilizing azoisobutyronitrile as an initiator at the temperature range of 65-70°C to give drug-polymer conjugates. The obtained materials were characterized by FT-IR, 1H-NMR, 13C-NMR and elemental analysis techniques to confirm their structures. The hydrolysis of drug-polymer conjugates was carried out in cellophane membrane dialysis bags containing aqueous buffer solutions (pH 1, 7.4 and 10) at 37°C for 24 h. Detection of hydrolysis solution by UV spectroscopy at selected intervals showed that naproxen can be released by hydrolysis of the ester bond between the drug and polymer backbone. The release profiles indicated that the hydrolytic behavior of polymeric prodrugs is strongly based on the polymer hydrophilicity and the pH value of the hydrolysis solution. The obtained results suggested that these polymeric prodrugs could be useful for release of naproxen in controlled release systems after in-vivo examinations.

Keywords: Naproxen, Non-steroidal anti-inflammatory Drugs, Polymeric Prodrugs, Drug Delivery Systems, Polymerization.