Study on Pharmacokinetics of Paclitaxel Liposome in rats

AIM To study the pharmacokinetics of paclitaxel liposome in rats. METHODS Plasma was extracted with tert-butyl methyl ether and norethisterone was employed as internal standard after iv. paclitaxel liposome and taxol injection in rats. Plasma samples were analyzed on a C_ 18 column at 227 nm and the mobile phase was methanol and water (65∶35,v/v). RESULTS Linearity was confirmed over the whole calibration range from 0.05 μg/ml to 50 μg/ml(r=0.9999). The intra- and inter-day precisions (RSD) of analysis were lower than 6% and the extraction recovery at three different concentration were better than 90%. The plasma concentration-time profile in rat after iv injection of paclitaxel liposome or taxol injection follow a bi-exponential disposition. T_ 1/2β are (11.19±0.08) h and (7.49±0.80) h, AUC are 2615.89±770.58(mg·L -1·min -1) and 904.94±25.36 (mg·L -1·min -1) respectively. CONCLUSION Paclitaxel liposome has a long-circulating action and improve bioavailabilty of paclitaxle in rat to some extent in comparison with conventional taxol injection.