Improved high-performance liquid chromatographic analysis of teniposide in human plasma

A simple and practical high-performance liquid chromatographic analysis has been developed for measuring teniposide (VM26) in human plasma. The present analytical method has improved extraction efficiency from human plasma, therefore allowing determination of VM26 in a clinical setting using ultraviolet detection alone. Furthermore, sample preparation was simplified and shortened through use of a one-step extraction procedure. VM26 and internal standard (ibuprofen) were extracted from human plasma (0.5 ml) with ethyl acetate. A phenyl muBondapak column eluted with a mobile phase, consisting of acetonitrile-distilled water-acetic acid (30:68:2, v/v/v) was used for separation, and quantitation was achieved with a UV monitor set at 240 nm. Average extraction efficiency was 96.8+/-6.6% for VM26 between 1 and 25 microg/ml, and 91.4+/-4.3% for internal standard, with both intra- and inter-day coefficients of variation being less than 10%. The detection limit with a 100-microl injection was estimated at 0.2 microg/ml with a signal-to-noise ratio of 3 for VM26 in human plasma. The stability data of VM26 in plasma, standard and stock solutions were also obtained. The present method was found to be an alternative to the previously reported method with an electrochemical detection, and can be easily applied to routine clinical pharmacokinetic studies of VM26.