Poly(D,L-lactic-co-glycolic acid)-based artesunate nanoparticles: formulation, antimalarial and toxicity assessments.

Objective: The aim of this study was to formulate polymer-based artesunate nanoparticles for malaria treatment.

Methods: Artesunate was loaded with poly(D,L-lactic-co-glycolic acid) (PLGA) by solvent evaporation from an oil-in-water single emulsion. Nanoparticles were characterized by X-ray diffraction and differential scanning calorimetry analyses. In vivo antimalarial studies at 4 mg/kg were performed on Swiss male albino mice infected with Plasmodium berghei. Hematological and hepatic toxicity assays were performed. In vitro cytotoxicity of free and encapsulated artesunate (Art-PLGA) to cell line RAW 264.7 was determined at concentrations of 7.8-1000 µg/ml.

Results: The particle size of the formulated drug was (329.3±21.7) nm and the entrapment efficiency was (38.4±10.1)%. Art-PLGA nanoparticles showed higher parasite suppression (62.6%) compared to free artesunate (58.2%, P<0.05). Platelet counts were significantly higher in controls (305 000.00±148 492.40) than in mice treated with free artesunate (139 500.00±20 506.10) or Art-PLGA (163 500.00±3535.53) (P<0.05). There was no sign of hepatic toxicity following use of the tested drugs. The half maximal inhibitory concentration (IC) of Art-PLGA (468.0 µg/ml) was significantly higher (P<0.05) than that of free artesunate (7.3 µg/ml) in the in vitro cytotoxicity assay.

Conclusions: A simple treatment of PLGA-entrapped artesunate nanoparticles with dual advantages of low toxicity and better antiplasmodial efficacy has been developed.