High-performance liquid chromatographic method with diode array detection for identification and quantification of the eight new antidepressants and five of their active metabolites in plasma after overdose.

A high-performance liquid chromatographic method is described for the determination of selective serotonin reuptake inhibitors (fluvoxamine, paroxetine, sertraline, fluoxetine, citalopram, mirtazapine), serotonin norepinephrine reuptake inhibitors (milnacipram, venlafaxine), a noradrenergic and specific serotoninergic antidepressant (mirtazapine), and five pharmacologically active metabolites (desmethylcitalopram, didesmethylcitalopram, norfluoxetine, O-desmethylvenlafaxine, desmethylmirtazapine). After a double-step liquid-liquid extraction, compounds are separated on a Symmetry C8 column eluted with a gradient of acetonitrile-phosphate buffer 10 mM pH 3.8 and detected at 230 nm and 290 nm. Calibration curves were linear in the range 25 to 500 ng/mL (100-2000 ng/mL for venlafaxine and its metabolite). The limit of quantification was 25 ng/mL (100 ng/mL for venlafaxine and its metabolite). For all quality controls good accuracy was achieved (93% to 99.5%) with intraday and interday variation coefficients less than 12%. This method allows simple and rapid (run time 18 min) identification and quantification of the eight new antidepressants and five of their active metabolites. This method can be used for toxicologic purpose.