This study aims to optimize the preparation technics of artemisinin (ART) loaded lactic-co-glycolic acid (PLGA) nanoparticles (PLGA-ART-NPs).The emulsification-solvent evaporation method was performed to prepare the nanoparticles.The influnences of emulisifier types (polyvinyl alcohol,Tween 80,and poloxamer),the concentrations of the emulisifier,water-oil ratio,and carrier-drug ratio on the particle size,encapsulation efficiency,and drug loading capacity were analyzed by a single factor analysis.The preparation technics of PLGA-ART-NPs were optimized by using drug loading capacity as the index based on a Box-Benhnken response surface method.The results indicated that polyvinyl alcohol had a better emulsification effect.Emulsifier concentration,water-oil phase ratio,and carrier-drug ratio were chosen as the influence factors and the optimal formulations were as follows:emulsifier concentration of 0.017 g/mL,water-oil phase ratio of 18∶1 (V/V),and carrier-drug ratio of 10∶1 (W/W).Drug loading rate for the nanoparticles prepared under the optimal conditions was detected to be (4.43±0.22)% together with zeta potential at -28.28±2.17 mV.The formulation process optimized in this work,therefore,is stable,reproducible and feasible,and the prepared nanoparticles possess a satisfying solution stability.

"> polylactic acid-glycolic acid copolymer, artemisinin nanoparticles, response surface method, single factor analysis, emulsification-solvent evaporation method