Preparation, physical characterization and pharmacokinetic study of paclitaxel nanocrystals

Paclitaxel (PTX) is a natural broad-spectrum anticancer drug with poor aqueous solubility. PTX nanocrystals were formulated to improve the water solubility, and PTX nanosuspensions were prepared using anti-solvent precipitation, and then organic solvent and surfactants were removed by filtering through a vacuum system. The physical characterization of PTX nanocrystals were measured by transmission electron microscope, X-ray diffraction and differential scanning calorimetry. In addition, saturation solubility, in vitro release, stability and pharmacokinetic characteristics were examined. The average particle size of PTX nanocrystals was ∼200 nm, and they had a stable potential and a uniform distribution. Paclitaxel nanocrystals can effectively improve drug solubility and in vitro release. PTX pharmacokinetic and tissue distribution studies were compared after intravenous administration of nanocrystals versus a commercial injection formulation. PTX nanocrystals were rapidly distributed with a longer elimination phase. Moreover, tissue distribution indicated that PTX nanocrystals are mainly absorbed by the liver and spleen and may offer reduced renal and cardiovascular toxicity which may reduce side effects.