Drug-delivery study and estimation of polymer-solvent interaction parameter for bisacrylate ester-modified Pluronic hydrogels.

In this study, Pluronic F127 hydrogels were characterised as an injectable system for the controlled release of drugs with variable molecular weights (FITC-Dextran at 70 and 40 kDa). In addition, the polymer-solvent interaction parameter (chi) was successfully estimated. Pluronic hydrogels (10-25 wt.%) were redox cured and their swelling behaviour investigated in PBS (pH 7.45) at 37 degrees C. After swelling to equilibrium, the hydrogels were compressed and the rubber-elasticity theory was applied to evaluate chi. Tensile tests proved the hydrogels were elastic and their chi values ranged between 0.50 and 0.53. The full drug load could be delivered over a period of approximately 15 h suggesting that redox cured Pluronic F127 hydrogels can function as injectable systems for controlled and sustained release of macromolecules.