Abstract: Hydrogel microparticles(microgel)based on natural polymers have been widely used as biomaterials due to their excellent biocompatibility. In this study,a series of dextran microgel were prepared using the inverse microemulsion technique. And,effects of the HLB value,emulsification method,volume ratio of water to oil(φ),molar ratio of water to emulsifier(R₀)on the morphology,and particle size of the dextran microgel were investigated. The results indicated that dextran microgels with particle size from 400nm to 70μm could be prepared with the CYH/Span 80-Tween 80/Dex-CHO emulsion system. Microgels prepared under ultrasonic had smaller particle size than that prepared under mechanical agitation. Dextran microgel with relatively small diameter at ～422nm was obtained with m_{(Tween 80)}/m_{(Span 80)}=0.10,HLB=5.27,φ =1/6. In addition,the particle size of the dextran microgel increased with the increase of the R₀ value. The dextran hydrogel microparticles based on the natural dextran with controllable particle size can be used as promising carrier materials for biomedical applications.

Key words: dextran, hydrogel microparticles, inverse microemulsion, particle size control

摘要： 基于天然高分子的水凝胶微球因具有良好的生物相容性，作为生物材料得到了广泛应用。本文采用反相微乳液交联技术制备了一系列葡聚糖水凝胶微球，并探讨了反相微乳液体系中表面活性剂的亲水亲油平衡值（HLB值）、乳化方式、水油相体积比（φ）、水相与表面活性剂的摩尔比（R₀）等因素对该葡聚糖水凝胶微球形貌及粒径的影响情况。结果表明：采用环己烷（CYH）/Span 80-Tween 80/醛基化葡聚糖（Dex-CHO）乳液体系制备所得葡聚糖水凝胶微球的粒径在400nm～70μm之间可调；相对于机械搅拌乳化，超声波乳化条件下获得的凝胶微球具有更小的粒径，且当复配乳化剂m_{（Tween 80）}/m_{（Span 80）}=0.10、HLB值=5.27、φ=1/6时，获得的凝胶微球粒径最小（约422nm）；葡聚糖凝胶微球的粒径随着R₀值的增加呈现增大趋势。该葡聚糖水凝胶微球粒径可控，是一类天然高分子水凝胶，有望作为载体材料应用于生物医学领域。

关键词: 葡聚糖, 水凝胶微球, 反相微乳液, 粒径调控