Drug release behaviors of a novel pH/temperature‐responsive chitosan‐poly(N‐acryloylglycinate) hydrogel

Abstract A pH/temperature and degradable‐responsive hydrogel (PSMEA) was prepared from chitosan (CS), N ‐acryloylglycine methyl ester (NAGME), N ‐acryloylglycine ethyl ester (NAGEE), acrylic acid (AA), and N ‐methylenebisacrylamide (NMBA). The swelling properties of PSMEA were systematically investigated at different temperatures, pH, and CS contents. It was found that the PSMEA demonstrated obvious pH and temperature‐responsive natures. The caffeine‐release behaviors showed that only 42.9% caffeine was released from PSEMA in pH 2.1 phosphate buffer solution (PBS) after 360 min, whereas more than 71.5% caffeine was gradually diffused into pH 7.4 PBS over the same time interval. In addition, the caffeine release was much higher at 37.0°C than that at 14.0°C in PBS medium. The apparent degradability of PSMEA was also observed in the pH 7.4 PBS at 37.0°C through the chemical cleavage of CS. As seen from the results, PSEMA seems to be a potential application in the drug‐delivery system controlled by the external pH value and temperature. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011