N，N＇-亚甲基双丙烯酰胺交联淀粉微球的制备及其降解性能研究

The Preparation and Degradability of Starch Microspheres Crosslinked with N,N'-methylene Bisacrylamide

以研究交联淀粉微球(CSM)制备工艺和降解性能为目的,采用单因素试验方法,分析了反应时间、反应温度、引发剂浓度、交联剂浓度对淀粉微球平均粒径的影响规律,用扫描电镜观测了样品形貌,用FT-IR对其结构进行了表征,利用In-Vitro消化模型,对不同粒径淀粉微球在人体内的降解性能进行了测定。结果表明:反应温度和反应时间与制备的淀粉微球平均粒径大小呈负相关,微球平均粒径随引发剂用量和交联剂用量增加而减小,达到最小值后又不断增大;交联淀粉微球形态圆整,表面略显粗糙,粒度均匀,红外光谱在1539cm-1处出现N—H弯曲振动的吸收峰,微球中存在酰胺基结构;CSM在人工胃液中的消化率与降解时间几乎成线性关系,4h内的消化率低于15%,在人工小肠液中的降解分两个阶段,前60min速度较快,60min后CSM的消化速度明显减慢,5h后消化率低于50%;CSM在人工消化液中的消化速度与其直径呈反比。表明交联淀粉微球可被人体缓慢降解,具有应用于药物缓释、靶向给药和栓塞治疗的前景。

The objective of this subject was to study the preparation process and degradability of crosslinked starch microsphere（CSM）. The effects of reaction time, reaction temperature, initiator concentration, crosslinker concentration on average diameter of CSM were studied. The samples of CSM were characterized by scan electron microscope, FT-IR spectroscopy. With In-Vitro degradability model, the degradability of CSM with different diameters was tested. Results showed that average diameter of CSM was negatively linked to reaction time and reaction temperature. Average diameter of CSM decreased with initiator and crosslinker concentrations, and reached a minimum and then increased. SEM and FT-IR analysis results indicated that CSM were spherical, even distributing particulates with rough surface and CSM had N--H bending vibration absorption at 1539cm^-1. The digestibility analysis results showed that as the CSM were degraded in simulated gastric fluid, a linear relationship existed between digestibility and degraded time, the high in the first 60 rain and became low significantly after 60 min. The degraded rate of CSM was negatively related to average diameter. So the CSM could be degraded slowly in human body and have prospects on the application to drug releasing, targeted drug delivery and curing embolization.