Development and validation of a high-performance liquid chromatography-tandem mass spectrometric method for simultaneous determination of bupropion, quetiapine and escitalopram in human plasma

In the present study, an effective high performance liquid chromatography-tandem mass spectrometric (HPLC/MS/MS) method was developed and validated to simultaneously determine bupropion (BUP), quetiapine (QUE) and escitalopram (ESC) in human plasma using carbidopa as the internal standard. Chromatographic separation was achieved on a Waters Sun Fire C18 column using reversed-phase chromatography. The MS/MS experiment was performed in positive ion multiple reaction monitoring mode to produce product ions of m/z 240.3 → 184.2 for BUP, 384.2 → 253.1 for QUE, 325.3 → 109.3 for ESC and 227.2 → 181.2 for the internal standard. The method showed good linearity (R(2) ≥ 0.997), precision (relative standard deviation ≤7.5%), satisfactory intra- and interday accuracy (88.4-113.0%) and acceptable extraction recovery (87.2-115.0%), matrix effect (84.5.5-108.7%) and stability (92.3-103.5%). The method was successfully applied to determine the concentrations of BUP, QUE and ESC in human plasma samples.