A simple and reliable method for quantifying plasma concentrations of tetracyclic antidepressants using monolithic silica solid-phase extraction tips

摘要: Three tetracyclic antidepressants, mianserin, mirtazapine, and setiptiline, were extracted from human plasma samples using a new micropipette solid-phase extraction tip containing monolithic silica gel packing material, the MonoTip C18. The (0.1 ml), which contained mixed with 330 μl of distilled water 50 μl 0.5 M glycine–sodium hydroxide buffer solution (pH 8). After centrifugation, supernatant was onto C18 phase (pipette volume, 200 μl) by 25 sequential aspirating/dispensing cycles. three analytes retained in eluted methanol 5 eluate subjected to measurements gas chromatography (GC) nitrogen–phosphorus detection (NPD). recoveries antidepressants 84.6–99.6% limits for each drug between 2.4 15 ng/ml plasma. maximum intraday interday coefficients variation drugs below 10.6%. Regression equations showed excellent linearity range 50–5000 ng/ml mianserin mirtazapine 50–10 000 ng/ml setiptiline. stable at least 12 h 4°C, 4 weeks −80°C, through freeze–thaw cycles validated method successfully used quantify concentrations subject after oral administration drug. Although we achieved analyte GC-NPD, present seems be very useful combining it GC–mass spectrometry (MS) and/or liquid chromatography–tandem MS secure high simplicity, purification, reproducibility, sensitivity.