关键词: 魔芋葡甘聚糖, 聚丙烯酸, 重均分子量, 药物载体, &beta, -甘露聚糖酶

Abstract: In this paper，a pH-sensitive interpenetrating polymer network（IPN）hydrogels designed for colon targeted drug delivery were prepared by using konjac glucomannan（KGM）with different molecular weights（1.070×106（KGM-1），8.272×105（KGM-2），7.329×105（KGM-3），and 6.012×105（KGM-4））and poly（acrylic acid）（PAA）with N,N-methylene-bis-（acrylamide）（MBAAm）as a cross-linker. The structure of the hydrogels was characterized by FTIR and SEM. The swelling ratio of these hydrogels had sensitive respondence to the environmental pH value variation. Hydrogels composed of higher molecular weights KGM had bigger swelling ratio than those hydrogels composed of lower molecular weights KGM. The enzymatic degradation tests showed that the IPN hydrogels retain the enzymatic degradation character of KGM，and hydrogels composed of lower molecular weights KGM can release drug more stably. These results showed that KGM with lower molecular weights could be a more suitable polymeric carrier for controlled release.

Key words: konjac glucomannan, poly(acrylic acid)；weight average molecular weight；drug delivery；β-mannanase