Temperature sensitive poly[N-isopropylacrylamide-co-(acryloyl β-cyclodextrin)] for improved drug release

The model drugs ibuprofen (IBU) and tegafur (T-Fu) were loaded into poly[N-isopropylamide (acryloyl β-cyclodextrin)][P(NIPA-co-A-CD)] and PNIPA hydrogels by immersing dried gels in IBU solutions until they reached equilibrium. Drug release studies were carried out in water at 25°C. In contrast to the release time of conventional PNIPA hydrogel, that of IBU from the β-CD incorporated hydrogel was significantly prolonged a the drug loading was also greatly incresed, which may be the result of the formation of inclusion complexes between CD and ibuprofen. However, another hydrophilic drug did not display these properties because it could not form a complex with the CD groups. Cumulative release of IBU from P(NIPA-co-A-CD) and PNIPA hydrogels as a function of time at 25 °C.