Preparation and in vitro release of mPEG-PLA microspheres of Panax notoginseng saponins

This study was performed to promote the clinical application of Panax notoginseng saponins (PNS), which present anti-inflammatory and antitumor activities, and provided insights for the preparation of controlled-release dosage forms of traditional Chinese medicine. A series of drug-loaded microspheres with degradable amphiphilic polymer material polyethylene glycol monomethyl ether-polylactic acid (mPEG-PLA) as the carrier was synthesized. The degradation, sustained-release behavior, and biocompatibility of the drug-loaded microspheres were studied through in vitro release, degradation, hemolysis, anticoagulation, and cytotoxicity experiments. The pharmacological activities of the microspheres were studied through anti-inflammatory and antitumor experiments. The results showed that the best carrier material was mPEG2k-PLA (1:9), with an average particle size of 3.47 ± 0.35 μm, a drug load of 5.50 ± 0.28 %, and an encapsulation efficiency of 38.52 ± 1.93 %. This material could be released stably for approximately 24 days and degrade in approximately 60 days. Moreover, the microspheres had good biocompatibility and anti-inflammatory and antitumor activities.