A REVERSED-PHASE HPLC METHOD DEVELOPMENT FOR THE SEPARATION OF NEW ANTIDEPRESSANTS

Abstract

A RPLC method with UV detection (225 nm) is developed for the separation of five SSRIs (fluvoxamine, fluoxetine, sertraline, paroxetine, and citalopram), two SNaRIS (venlafaxine and milnacipran), one NaSSA (mirtazapine), and four active metabolites (norfluoxetine, desmethylcitalopram, desmethylvenlafaxine, and desmethylmirtazapine). A standard solution (20 μg/mL) of the twelve compounds is analysed under isocratic conditions on two new-generation RP columns (Satisfaction® RP 18 AB and Satisfaction® C8+, 250 mm × 4.6 mm, 5 μm). Mobile phase composition (acetonitrile content, pH of the aqueous buffer) and temperature are varied and the effect of these parameters on the retention factors of the antidepressants is examined. Similar elution profiles are observed with the two stationary phases, but the separation of all the solutes is only possible on the RP 18 AB column. It can be achieved at 45°C (or 50°C) with a mobile phase consisting of a mixture of potassium dihydrogen phosphate (pH 4.8, 25 mM)-acetonitrile (65:35, v/v) (flow rate: 1 mL/min). The run time is 20 min and a baseline resolution is obtained for all the analytes allowing this procedure to be well suited for a rapid toxicological screening.