High-performance liquid chromatographic assay for the measurement of atovaquone in plasma.

A rapid and efficient isocratic high-performance liquid chromatographic assay for the measurement of atovaquone in plasma has been developed and validated. The drug was extracted from plasma with organic solvents, assayed on a C1 column with a mobile phase of methanol-0.1% acetic acid (70:30, v/v), and detected by ultraviolet absorbance at 254 nm. Recovery of atovaquone from plasma was greater than 85%. Intra- and inter-assay variability were less than 8%, and the average accuracy of the assay (expressed as % bias) ranged from -7.4 to + 2.2%. The upper and lower limits of quantitation were 100 and 0.25 microgram/ml, respectively. Measurement of atovaquone in spiked plasma control samples during routine runs of clinical trial samples confirmed the reliability of the assay.