Determination of lumefantrine in rat plasma by liquid-liquid extraction using LC-MS/MS with electrospray ionization: assay development, validation and application to a pharmacokinetic study.

A simple, sensitive and rapid method for the analysis of lumefantrine in rat plasma using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was developed. Detection was performed by positive ion electrospray ionization (ESI) in multiple reaction monitoring (MRM) mode. The method included a chromatographic run of 5 min using a C(18) analytical column and the calibration curve was linear over the concentration range of 2-500 ng/mL with a correlation coefficient (r) of 0.996 or better. The intra- and inter-day assay precision ranged from 1.5 to 7.5% and 5.5 to 7.7%, respectively, and intra- and inter-day assay accuracy was between 91.3-109.7% and 97.0-104.7%, respectively. The method was successfully applied for the pharmacokinetic study in rats.