温度敏感型淀粉基聚合物载体的制备、表征及性能分析

本研究以木薯淀粉为原料制备了温度敏感型聚合物载体(PEG-St-R),并用于探究缓释机制和一定的温度响应性。首先以异丙基缩水甘油醚作为疏水基团和温敏性基团,制备了疏水性木薯淀粉聚合物(St-R),然后将聚乙二醇(mPEG)作为亲水基团,通过酯化反应成功制备了温度敏感型木薯淀粉基聚合物(PEG-St-R)。并利用芘的荧光探针法对聚合物的自组装行为进行了表征,发现聚合物的临界胶束浓度(CMC)为0.339 mg/mL。用透射电镜辅助观察其形貌特征,能明显的观察到聚合物组装形成球形结构,并进一步测定胶束的粒径,粒径集中分布在28和122 nm附近。此外,通过负载功能性成分姜黄素以探究其负载性能,当材料投入100 mg,姜黄素投入量为14 mg时,胶束有最大负载量,负载量为18.47%。在不同温度下磷酸缓冲溶液(PBS)中探究累计缓释量的变化,通过缓释曲线可以较明显地观察到负载胶束在60 h内,37℃环境中的胶束累计释放量达到了43.9%,25℃环境中的负载胶束累计释放量只有34.7%,展现出良好的温度敏感性能。为木薯淀粉功能化和纳米胶束载体的制备提供了理论基础,并为制备温度敏感型淀粉基聚合物载体提供了良好平台。

Preparation,Characterization and Performance Analysis of Temperature-Sensitive Starch-Based Polymer Carrier

In this study,a temperature-sensitive polymer carrier(PEG-St-R)was prepared from tapioca starch as a raw material,and was used to explore the mechanism of sustained release and a certain temperature response. First,a hydrophobic tapioca starch polymer(St-R)was prepared with isopropyl glycidyl ether as a hydrophobic group and a temperature-sensitive group,and then polyethylene glycol(mPEG)was used as a hydrophilic group. The temperature-sensitive cassava starch-based polymer(PEG-St-R)was successfully prepared by esterification. The self-assembly behavior of the polymer was characterized by the fluorescent probe method of europium,and the critical micelle concentration(CMC)of the polymer was found to be 0.339 mg/mL. With the help of transmission electron microscope to observe its morphological characteristics,it could be clearly observed that the polymer assembled into a spherical structure,and the particle size of the micelles was further determined. The particle sizes were concentrated around 28 and 122 nm. In addition,by loading the functional component curcumin to investigate its loading performance,when the material was injected with 100 mg and the curcumin was injected with 14 mg,the micelles have the maximum load and the load was 18.47%. At different temperatures,the change of cumulative slow-release was explored. Through the slow-release curve,it could be clearly observed that the cumulative release of micelles in the environment of 37 ℃ reached 43.9% in 60 h. The cumulative release of loaded micelles at 25 ℃ was only 34.7%,showing good temperature sensitivity. It provides a theoretical basis for the functionalization of cassava starch and the preparation of nano-micelle micelles,and provides a good platform for the preparation of temperature-sensitive starch-based polymer carriers.