Simultaneous Determination of Voriconazole and Posaconazole Concentrations in Human Plasma by High-Performance Liquid Chromatography

A simple, sensitive, and selective high-performance liquid chromatographic method for the simultaneous determination of voriconazole and posaconazole concentrations in human plasma was developed and validated. Quantitative recovery following liquid-liquid extraction with diethyl ether was achieved. Linearity ranged from 0.10 to 20.0 mu g/ml for voriconazole and from 0.05 to 10.0 mu g/ml for posaconazole. The intra- and interday coefficients of variation were less than 8.5%, and the lower limits of quantitation were < 0.05 mu g/ml.