Determination of abacavir in human plasma by high‐performance liquid chromatography with ultraviolet detection and the analytical error function

A rapid and simple high‐performance liquid chromatography method has been developed for the determination of the HIV‐1 reverse transcriptase inhibitor abacavir in human plasma. It included a single liquid–liquid extraction procedure with a mixture of ethyl acetate‐diethyl ether prior to reversed‐phase chromatography on a C 18 column and C 18 precolumn insert. Ultraviolet detection was set at 285 nm. The mobile phase consisted of water–acetonitrile (83:17, v/v) and the ow rate was kept at 1 mL/min. The total run time for a single analysis was 10 min. The method has been validated over the range 50–2500 ng/mL. The assay was linear over the entire concentration range ( r 2 = 0.9993). Intra‐ and inter‐day precision and accuracy were less than 8.1 and −5.2%, respectively. The extraction recovery was greater than 94.3%. Abacavir was stable under the relevant storage conditions tested. After the validation, the analytical error function was established as standard deviation (SD; ng/mL) = −1.072 + 0.037 C ( C = theoretical concentration value). The method developed and its associated analytical error function will be suitable for pharmacokinetic studies and monitoring of HIV‐1 patients. Copyright © 2004 John Wiley & Sons, Ltd.