Wang Kang, He Zhimin
Enzyme Technology Laboratory, Chemical Engineering Research Center, Tianjin University, Tianjin 300072, PR China.
Int J Pharm. 2002 Sep 5;244(1-2):117-26. doi: 10.1016/s0378-5173(02)00324-1.
Controlled release beads were prepared by using alginate (ALG), konjac glucomannan (KGM) and chitosan (CHI). Bovine serum albumin and insulin were used as model proteins for in vitro assessments. It was observed that KGM could be contained within beads, and faintness hydrogen binding and electrostatic interaction exist between ALG and KGM by infrared spectra. Clear dents were found on the surface of beads using KGM by scanning electron microscopy. Use of KGM could help increase the payload of drug. After beads were treated by 0.1 N HCl for 4 h and put into pH 7.4 buffers, protein was released from ALG-CHI beads within 1 h, while it was lost from ALG-KGM-CHI beads for 3 h. However, the leaking of protein from ALG-KGM-CHI beads was also increased in 0.1 N HCl solution. Concentration of gelling ion had great effect on release rate and gel structure. Studies of water of hydration had shown that swelling of ALG-KGM-CHI beads was higher than that of ALG-CHI beads in acidic solution, but the opposite result was obtained in alkali solution. The result indicated that the diffusion of protein was related to the viscosity and swelling properties of KGM.
采用海藻酸钠（ALG）、魔芋葡甘聚糖（KGM）和壳聚糖（CHI）制备控释微珠。以牛血清白蛋白和胰岛素作为模型蛋白进行体外评估。观察到KGM可被包裹在微珠内，通过红外光谱发现ALG与KGM之间存在微弱的氢键和静电相互作用。使用扫描电子显微镜观察发现，含KGM的微珠表面有明显凹痕。使用KGM有助于增加药物载量。微珠经0.1 N盐酸处理4小时后放入pH 7.4的缓冲液中，蛋白质在1小时内从ALG-CHI微珠中释放出来，而从ALG-KGM-CHI微珠中释放则持续3小时。然而，在0.1 N盐酸溶液中，ALG-KGM-CHI微珠中蛋白质的泄漏也有所增加。胶凝离子浓度对释放速率和凝胶结构有很大影响。水合水研究表明，在酸性溶液中，ALG-KGM-CHI微珠的溶胀度高于ALG-CHI微珠，但在碱性溶液中结果相反。结果表明，蛋白质的扩散与KGM的粘度和溶胀特性有关。
