Preparation and Evaluation of Novel Emodin-loaded Stearic Acid-g-chitosan Oligosaccharide Nanomicelles

The purpose of this study was to prepare and characterize emodin-loaded stearic acid-g-chitosan oligosaccharide (CSO-SA/EMO) and to evaluate its antitumor activity in vitro. In this study, stearic acid-g-chitosan oligosaccharide was used as a carrier and its physicochemical properties were determined by different methods. Cell uptake behavior was examined using FITC-labeled stearic acid-g-chitosan oligosaccharide. CSO-SA/EMO was prepared using ultrasonication and dialysis. Particle size, surface potential, entrapment efficiency, and drug release behavior were studied in vitro. The effects of CSO-SA/EMO on gastric cancer cells were investigated using MTT assay and flow cytometry. Results showed CSO-SA/EMO particle size was larger and potential was smaller than that of stearic acid-g-chitosan oligosaccharide. The 12 h micellar uptake by MGC803 and BGC823 cells was sufficient, and the micelles were able to abundantly accumulate at lesion sites in mice thus achieving good passive EPR targeting. MTT and cell cycle arrest assays showed CSO-SA/EMO-enhanced antitumor activity significantly towards MGC803 and BGC823 cells compared with that of free emodine. Tumor volume, hematoxylin and eosin staining, and terminal deoxynucleotide transferase dUTP nick-end labeling assay proved CSO-SA/EMO had a significant antitumor effect on tumor tissues in vivo. In conclusion, the ultrasonication-dialysis method provided a simple and effective method for preparing CSO-SA/EMO. The delivery of emodine using a micelle system improved its antitumor effects effectively.