A Rapid and Sensitive UPLC-MS/MS Method for Determination of Docetaxel in Rabbit Plasma: Pharmacokinetic Study of New Lung-Targeting Docetaxel Liposome at Low Dose.

In this study, a more rapid and more sensitive ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method is developed and validated for the pharmacokinetic study of a new lung-targeting docetaxel liposome (DTX-LP) at low dose (1 mg/kg) in rabbits. The method is reliable and reproducible with intra-day precision below 5.75 %, inter-day precision below 7.57 %, and mean extraction recovery of 84.1-91.7 %. At low dose, the validated method is successfully applied to the comparative pharmacokinetic study of docetaxel (DTX) in rabbit plasma after intravenous administration of DTX-LP and DTX injection, respectively. The results indicate that the pharmacokinetic profile of DTX is completely changed when loaded in the new type of liposome, which can make DTX quicker distribution from the circulation to the target organ and slower eliminated from the body.