[Comparison of preparing two polylactide nanoparticles loaded lipophilic anti-cancer herb drug by nanoprecipitation method].

This paper introduced an experimental study of polylacticacid (PLA) nanoparticles of lipophilic anti-cancer herb drug using a precipitation method. Cucurbitacins (Cu) and Curcuminoids (Cur) were selected to be model drugs. They had similar solubility but their incorporation effects were significantly different: the average drug entrapment ratio, the average drug loading and the average drug recovery were 38.53%, 2.21% and 27.02% respectively; while those of Cur-PLA-NP were 94.36%, 14.35% and 91.23% respectively. To analyse the reason, drug incorporation process was investigated. By measuring solvent evaporation rate, ratio of drug PLA precipitates, drug distribution in system and entrapping ratio at different time of preparation, we found the difference of precipitation velocity of drug was the main reason. We also concluded that not all lipophilic drug can be well entrapped into PLA nanoparticle by nanoprecipitation method. The drug incorporation depended on the interations among drug, PLA and organic solvents, in addition to the solubility of the drug.

[The preparation of the polylacticacid nanoparticles of cucurbitacin and their drug loading].

This paper introduced an experimental study of the preparation of polylacticacid (PLA) nanoparticles of cucurbitacin (CuC) using a precipitation method. The residual acetone, ratio of CuC PLA precipitates, and the relationships between the ratios of two precipitates and drug incorporation rates were measured. It appeared that the nanoparticles with 60% of PLA incorporated with 5.5% of CuC were formed when acetone was injected into the aqueous phase. As the acetone gradually evaporated, drug incorporation/encapsulation continued, with most of CuC (about 70%) formed new crystalline cores and suspended in the form of microcrystals in the medium, resulting a suspension containing both nanoparticles and microcrystals. We also concluded that this system may not necessarily be suitable for all lipophilic drugs to be prepared to PLA nanoparticles with good incorporation rate. The drug incorporation depended on the interactions among drug, PLA, and organic solvents, in addition to the solubility of the drug.