以三七总皂苷壳聚糖纳米粒为例探讨超滤离心法在包封率评价中的可靠性

目的 以建立三七总皂苷壳聚糖纳米粒(PNS-NPs)包封率的测定方法为例,探讨可能导致包封率测定错误结果的原因及解决方法。方法 通过加入促透剂,破坏皂苷分子的聚集状态,进而使用超滤离心法分离PNS-NPs中包封药物与游离药物,以避免游离药物被超滤膜非特异性截留。本实验对促渗剂类型进行了选择,对超滤离心方法的回收率与重复性进行了方法学验证,并对多批次的PNS-NPs的包封率进行了测定。结果 该方法能有效实现壳聚糖纳米粒中包封药物与游离药物的分离,回收率,重复性满足测定要求。结论 所建立的分离方法可适用于易产生分子间缔合药物的纳米制剂包封率测定,避免误导性的实验结果。

Reliability of Ultrafiltration Centrifugation in the Evaluation of Entrapment Efficiency: A Case Study of Panax notoginseng Saponins Chitosan Nanoparticles

OBJECTIVE To establish a method for determining the entrapment efficiency of Panax notoginseng saponin chitosan nanoparticles(PNS-NPs), and to explore the causes and solutions that may lead to wrong results. METHODS The aggregation state of saponin molecules was destroyed by adding penetration enhancers, and then the encapsulated drugs and free drugs in PNS-NPs were separated by ultrafiltration centrifugation, to avoid nonspecific interception of free drugs by ultrafiltration membrane. In this experiment, the type of penetration enhancer was selected, the recovery and repeatability of ultrafiltration centrifugation method were verified, and the entrapment efficiency of multiple batches of PNS NPs was measured. RESULTS The method can effectively separate encapsulated drugs from free drugs in chitosan nanoparticles, and the recovery and repeatability meet the requirements of determination.. CONCLUSION The separation method can be applied to the determination of encapsulation efficiency of nano preparations prone to intermolecular association drugs, so as to avoid misleading experimental results.