A systematic physicochemical investigation on solubilization and in vitro release of poorly water soluble oxcarbazepine drug in pluronic micelles

The solubilization of hydrophobic drug oxcarbazepine (OXC) in different pluronics viz. F108, F127 and P84 have been studied employing state of art techniques. The results from UV-vis spectroscopy reveals that the solublization capacity of pluronic P84 is higher as compared to other two pluronics F108 and F127 from where we speculated that larger corona region of pluronic micelles acted as barrier for the movement of drug into core. The locus of OXC in different pluronic micelles has been adjudged by H-1 NMR and isothermal titration calorimetry (ITC) measurements. In case of P84, an upfield chemical shifts in PPO (poly-propylene oxide) protons and a net endothermic process in the presence of OXC confirms that more amount of OXC is solubilized in core region whereas opposite results have been observed in case of pluronic F108 and F127. Dynamic light scattering (DLS) has been employed to determine the hydrodynamic diameter (D-h) of loaded and unloaded micelles. A significant difference between Dh of loaded and unloaded micelles assure that OXC was solubilized in pluronic micelles. In vitro drug release study of three different pluronic formulations show sustained release behaviour according to their locus of solubilization. The present results demonstrate that via drug-pluronics interaction and drug location study, we can tune the drug release behaviour from the pluronic micelles. (C) 2016 Elsevier B.V. All rights reserved.