RESUMEN
<p><b>OBJECTIVE</b>To optimize formulation of tanshinone II(A)-loaded PLGA nanoparticles and compare the difference of two methods in preparation and quality of nanoparticles.</p><p><b>METHOD</b>The two methods were nanoprecipitation method and emulsion-evaporation method. Single factor experiments and central composite design and response surface method were used to optimize the formulation of nanoparticles. The nanoparticles were characterized at size, morphology, entrapment efficiency, drug loading, drug recovery rate, crystallinity and drug release in vitro.</p><p><b>RESULT</b>The mean diameters were 225 nm and 183 nm, the entrapment efficiency were 95.49% and 87.99%, the drug loading were 2.03% and 0.16%, and the drug recovery rates were 38.42% and 17.59% respectively for nanoprecipitation method and emulsion-evaporation method.</p><p><b>CONCLUSION</b>Nanoprecipitation method was better than emulsion-evaporation method for preparation of tanshinone II(A)-loaded PLGA nanoparticles.</p>