交联β-环糊精-可溶性淀粉聚合物微球的合成及载药性质

Preparation and drug absorption characterization of crosslinked β-CD and water-soluble starch microspheres

目的用β-环糊精和可溶性淀粉作为原料合成不溶于水的微球,并对其吸附载药性质进行研究。方法使用反相悬浮交联法制备聚合物微球,对其乳化及交联过程的各个因素进行考察,并且以水杨酸为模型药物,考察了交联反应不同因素对水杨酸载药量的影响。探讨了药物的吸附动力学和吸附热力学。用傅立叶红外色谱仪、粉末X射线衍射、激光衍射粒度分析仪等手段对微球的性质进行研究。结果与结论β-环糊精与可溶性淀粉和环氧氯丙烷的用量比例为9 g∶1 g∶12 mL、氢氧化钠质量分数为40%、水相油相体积比为15∶120、乳化剂用量为7.0 g、搅拌速度为400 r.min-1、60℃下交联8 h可以获得粒径为100μm左右、粒径分布较窄、形状圆整的微球。红外光谱证明β-环糊精和可溶性淀粉在交联后结构和性质发生变化,交联后生成的三维网络结构使其具有较大的机械强度和吸附能力,可以作为药物载体。实验结果表明交联微球对水杨酸的吸附很快,1 h可达到平衡,平衡时包封率达到58.35%,载药质量分数为4.856%,而且主要为物理吸附过程。

Objective To prepare and characterize hydrophilic but indissoluble microspheres from β-CD and water-soluble starch. Drag absorption of this kind of microspheres was studied by using salicylic acid as model drug. Methods An inverse suspension polymerization method was used to synthesize microspheres from cross-linked β-CD and water-soluble starch, and influence factors were studied. Fourier-transformed infrared spectroscopy, X-ray powder diffraction and laser particle size analyzes were employed to characterize the microshperes. The absorption of salicylic acid by microspheres was studied under different conditions （time, temperature and initial concentration）. Results and Conclusion When the ratio of β-CD, soluble starch and EH ratio was 9 g： 1 g： 12 mL, the concentration of NaOH was 0.4 kg·L^-1, the amount of emulsifier was 7.0 g and the stirring rate was 400 r.min-1 ,fine emulsion were gained after 15 min stirring,then the reaction was continued for 8 h at 60℃. The microspheres with the diameter around 100μm, a narrow particle size distribution（PSD） and good spherical shape was gained. Data from Fourier-transformed infrared spectroscopy and thermoanalysis proved that the structures, characters ofβ-CD and soluble starch had been changed after cross-linking. Its good rigidity and absorbing ability were proved by three-dimension network. Therefore it can be used as drug carrier. The drug loading and entrapment are 4. 856% and 58.35% ,respectively.