Abstract: In this study, chitosan nanoparticles prepared by ionic cross-linking was considered as a new vehicle for the improvement of the water solubility and biocompatiblity of ginsenoside Rh2. Based on the size and zeta potential of nanoparticles, the conditions for preparing ginsenoside Rh2-loaded nanoparticles were optimized with respect to mass ratio between chitosan and sodium tripolyphosphate, the molecular mass of chitosan and the feeding amount of Rh2. The morphology of Rh2-loaded nanoparticles was observed transmission electron microscopy and atomic force microscopy. The change of crystal types was investigated by X-ray diffraction. The anti-proliferation effect of Rh2-loaded nanoparticles on non-small cell lung cancer cells (A549) and the cellular uptake of Rh2 were studied. Under the optimal conditions as follows: mass ratio of chitosan to Rh2 to sodium tripolyphosphate 8:1.5:2 and chitosan molecular mass 50 kDa, Rh2-loaded nanoparticles whose average particle size and zeta potential were (222.70 ± 17.34) nm and (46.50 ± 2.57) mV, respectively were obtained with encapsulation and loading efficiencies of 7.89% and 49.54%, respectively. The as-prepared nanoparticles showed uniform size distribution and good stability, therefore being suitable for drug delivery. It could be uptaken by A549 cells and have higher inhibitory effect on the proliferation of A549 cells compared with free ginsenoside Rh2. Therefore, the chitosan nanoparticles prepared by ionic cross-linking are a promising carrier for the delivery of ginsenoside Rh2.

Key words: chitosan; nanoparticles; ionic cross-linking; ginsenoside Rh2