Development of an assay method for the detection and quantification of protease and non-nucleoside reverse transcriptase inhibitors in plasma and in peripherical blood mononuclear cells by liquid chromatography coupled with ultraviolet or tandem mass spec

We present a simple chromatographic method to detect and quantify protease inhibitors (PI), metabolites and non-nucleoside reverse transcriptase inhibitors (NNRTIs) in human plasma of HIV-1 infected patients and in peripheral blood mononuclear cells (PBMCs) using either liquid chromatography coupled with ultraviolet (LC–UV) or liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS). A solid–liquid extraction was carried out on 500 μl of plasma as pre-treatment. Calibration curve ranges were from 50 (100) to 5000 ng/ml (indinavir). PBMC pellets from 7 ml of blood were lysed with methanol/tris with a calibration curve ranging from 0.25 to 250 ng/pellet. Simple modifications in the mobile phase composition (slight increase of ammonium acetate concentration and addition of methanol for LC–UV) easily linked the two analytical systems.