Curcumin loaded hydrogels as probable drug delivery systems

Hydrogels of crosslinked poly n-isopropyl acrylamide (PNIPAAm) and poly vinyl alcohol (PVA) were prepared by gamma-irradiation of the aqueous solutions. Curcumin, a pigment from curcuma longa exhibiting several important pharmacological activities, was loaded into these hydrogels. Following absorbance at 426 nm, quantitative estimation of the amount of loaded curcumin was made. The absorption and fluorescence spectra of curcumin in hydrogels indicate that it resides in the hydrophobic pockets of the gel. The kinetics of release of curcumin from the hydrogel in to aqueous Tx-100 surfactant solutions was also followed which indicated that release of curcumin from PVA hydrogel was efficient even at low (3 mM) surfactant concentration, while release from PNIPAAm hydrogel was efficient only at high (>30 mM) surfactant concentrations. The studies indicate that hydrogels can be employed as suitable systems for the delivery of curcumin, which is known for its excellent skin protecting properties.