Quantification of eight new antidepressants and five of their active metabolites in whole blood by high-performance liquid chromatography-tandem mass spectrometry.

A liquid chromatography-tandem mass spectrometry method is described for the blood determination of selective serotonin reuptake inhibitors (fluoxetine, paroxetine, sertraline, fluvoxamine, and citalopram), serotonin noradrenaline reuptake inhibitors (milnacipram and venlafaxine), a noradrenergic and specific serotoninergic antidepressant (mirtazapine) and five of their active metabolites (norfluoxetine, desmethylcitalopram, didesmethylcitalopram, desmethylvenlafaxine, and desmethylmirtazapine). After a liquid-liquid extraction from blood, the compounds and the internal standard (methylrisperidone) were eluted on a XTerra RP18 column with a gradient of acetonitrile/ammonium formate buffer 4 mmol/L pH 3.2. They were then detected by electrospray ionization mass spectrometry with multiple reaction monitoring mode. The calibration curves were linear over the range 5-500 ng/mL (20-2000 ng/mL for venlafaxine and desmethylvenlafaxine). The limit of quantification was set at 5 ng/mL for each compound (except for venlafaxine and desmethylvenlafaxine: 20 ng/mL). The bias were lower than 12%. Intraday and interday precisions, expressed as variation coefficient, were lower than 11%. The extraction recoveries were between 70 and 90% except for desmethylmirtazapine, desmethylvenlafaxine, milnacipram, and didesmethylcitalopram. This specific and sensitive method allows management of intoxication and is suitable for the routine determination of antidepressants in forensic investigations.

Quantification of tricyclic antidepressants and monoamine oxidase inhibitors by high-performance liquid chromatography-tandem mass spectrometry in whole blood.

Here we describe a liquid chromatography-tandem mass spectrometry method for the blood determination of tricyclic antidepressant drugs (amitriptyline, clomipramine, trimipramine, and imipramine, doxepin, mianserin, maprotyline, dosulepine, amoxapine), their active metabolites (desipramine, nortriptyline, demethylclomipramine, and nordoxepin), and monoamine oxidase inhibitors (toloxatone and moclobemide). A nontricyclic antidepressant (viloxazine) and two other anxiolytic drugs (buspirone and hydroxyzine) that could be encountered in toxicology have been included to this method. After a liquid-liquid extraction from blood, the compounds and their internal standard (methylrisperidone) were eluted on a XTerra RP18 column with a gradient of acetonitrile/ammonium formate buffer 4 mmol/L (pH 3.2). They were then detected by electrospray ionization mass spectrometry with multiple reaction monitoring mode. The calibration curves were linear over the range 5-100 ng/mL. The limit of quantification was 2 ng/mL for each compound. The bias were lower than 10%. Intraday and interday precisions, expressed as variation coefficient, were lower than 13%. The extraction recoveries were between 60 and 80% except for moclobemide, viloxazine, and toloxatone (10-60%). This specific and sensitive method allows management of intoxication and is suitable for the routine determination of antidepressants in forensic investigation.