부산대학교 도서관

This study examines the application of a pH-responsive hydrogel with a semi-interpenetrating polymeric network (semi-IPN) as a controlled drug release system. The hydrogel is synthesized from biodegradable materials, namely, polyvinylpyrrolidone, sodium alginate and acrylic acid, using a simple conventional heating method. Structural and morphological characterizations are performed using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The semi-IPN hydrogel shows high porosity, good swelling properties and noticeable pH-responsivity. Paracetamol, which is a common analgesic and antipyretic drug, is used as a model to study the application of the prepared hydrogel as a pH-controlled drug release system. The drug is loaded using a post-loading method, in which the loading percentage is equal to 96%. The results of in vitro release studies shows that the hydrogel performs a higher rate of paracetamol release in alkaline mediums, where 98.5% of paracetamol is released after 4 h, in comparison with restricted and relatively slow release in acidic medium. The determination of the mechanism that governs drug release is accomplished with Korsmeyer-Peppas model, and the results indicated a supper-case II mechanism. In addition, the amount of crosslinker is found to have a noticeable effect on the adsorption and in vitro release of the drug from the hydrogel. These results suggest the possibility of using the prepared hydrogel as potential site-specific drug release system, particularly for short term release of drugs that must be absorbed in the small intestine rather than the stomach. [ABSTRACT FROM AUTHOR]