Synthesis and Hydrolysis of Polyurethanes Containing Ibuprofen Pendent Groups

Abstract

New biodegradable polyurethanes and polyetherurethanes having hydrolytically labile ibuprofen groups as a therapeutic agent were prepared by reacting 1,6-hexamethylenediisocyanate (HDI), ethylene glycol with ibuprofen monoglyceride as a chain extender. The polyetherurethanes containing ibuprofen pendent groups were prepared by reacting poly(ethylene glycol) with an excess of HDI to obtain a prepolymer which was reacted with ibuprofen monoglyceride low molecular weight diol. The structure of the polymers was confirmed by FTIR and 1H NMR spectroscopy. The hydrolysis of the polymers was carried out in dialysis bags containing aqueous buffer solution (pH 8) at 370C. UV spectroscopy was used to show that ibuprofen was released by hydrolysis of the ester bond between the drug and polyurethane monoglyceride segments. The polyurethane-drug conjugates have longer duration of activity, due to slow release of ibuprofen.