Simultaneous quantification of rosiglitazone and its two major metabolites, N-desmethyl and p-hydroxy rosiglitazone in human plasma by liquid chromatography/tandem mass spectrometry: Application to a pharmacokinetic study

Abstract

We present a simple, rapid, and sensitive liquid chromatography (LC)–tandem mass spectrometry (MS/MS) method for the simultaneous quantification of rosiglitazone and its two major metabolites via CYP2C8/9, N -desmethyl and p-hydroxy rosiglitazone, in human plasma. The procedure was developed and validated using rosiglitazone-d 3 as the internal standard. Plasma samples (0.1 ml) were prepared using a simple deproteinization procedure with 0.2 ml of acetonitrile containing 40 ng/ml of rosiglitazone-d 3. Chromatographic separation was carried out on a Luna C 18 column (100 mm × 2.0 mm, 3-μm particle size) using an isocratic mobile phase consisting of a 60:40 (v/v) mixture of acetonitrile and 0.1% formic acid (aq). Each sample was run at 0.2 ml/min for a total run time of 2.5 min per sample. Detection and quantification were performed using a mass spectrometer in selected reaction-monitoring mode with positive electrospray ionization at m/ z 358.1 → 135.1 for rosiglitazone, m/ z 344.2 → 121.1 for N -desmethyl rosiglitazone, m/ z 374.1 → 151.1 for p-hydroxy rosiglitazone, and m/ z 361.1 → 138.1 for rosiglitazone-d 3. The linear ranges of concentration for rosiglitazone, N -desmethyl rosiglitazone, and p-hydroxy rosiglitazone were 1–500, 1–150, and 1–25 ng/ml, respectively, with a lower limit of quantification of 1 ng/ml for all analytes. The coefficient of variation for assay precision was less than 14.4%, and the accuracy was 93.3–112.3%. No relevant cross-talk and matrix effect were observed. This method was successfully applied to a pharmacokinetic study after oral administration of a 4-mg rosiglitazone tablet to healthy male Korean volunteers.