Hong Yeon-Ji, Kim Jin-Chul
School of Biotechnology and Bioengineering and Institute of Bioscience and Biotechnology Kangwon National University, 192-1, Hyoja 2-Dong, Chunchon, Kangwon-Do 200-701, Korea.
J Nanosci Nanotechnol. 2011 Jan;11(1):204-9. doi: 10.1166/jnn.2011.3042.
Egg phosphatidylcholine (EPC) liposomes incorporating hydrophobically modified chitosan (HmCh) were prepared by a sonication method. In order to immobilize chitosan on the surface of EPC liposomes, pentyl chains were covalently attached to chitosan. Following the proton NMR spectrum, the number of pentyl chains per chitosan molecule was calculated to be 2.5. Once the ratio of HmCh to EPC was kept below 1:5, the degrees of fluorescence quenching in the liposomal suspension were greater than 70%, indicating a high yield of liposome formation. No significant release from the liposome was observed in neutral and akali condition. The liposomes started to release their content at pH 6.5, and the release became more extensive as the pH of release medium decreased. The pH-sensitivity of the liposomes in terms of the release strongly depended on the amount of HmCh incorporated in liposomes.
采用超声法制备了包载疏水改性壳聚糖（HmCh）的蛋黄卵磷脂（EPC）脂质体。为了将壳聚糖固定在EPC脂质体表面，戊基链通过共价键连接到壳聚糖上。根据质子核磁共振谱，计算出每个壳聚糖分子的戊基链数为2.5。一旦HmCh与EPC的比例保持在1:5以下，脂质体悬浮液中的荧光猝灭程度大于70%，表明脂质体形成产率较高。在中性和碱性条件下未观察到脂质体有明显释放。脂质体在pH 6.5时开始释放其内容物，并且随着释放介质pH值的降低，释放变得更加广泛。脂质体在释放方面的pH敏感性强烈依赖于脂质体中HmCh的含量。
