A simple and sensitive HPLC‐fluorescence method for quantification of MDMA and MDA in blood with 4‐(4,5‐diphenyl‐1 H ‐imidazol‐2‐yl)benzoyl chloride (DIB‐Cl) as a label

A sensitive high‐performance liquid chromatographic method with fluorescence detection to determine 3,4‐methylenedioxymethamphethamine (MDMA) and 3,4‐methylenedioxyamphethamine (MDA) in human and rat whole blood or plasma samples was developed by using 4‐(4,5‐diphenyl‐1 H ‐imidazol‐2‐yl)benzoyl chloride (DIB‐Cl) as a label. MDMA and MDA in a small amount of blood sample ( ca 100 µL) were extracted by liquid–liquid extraction with ethyl acetate, and were derivatized with DIB‐Cl under mild conditions (10 min at room temperature). A good separation of DIB‐derivatives could be achieved within 45 min using a commercially available ODS column with an isocratic eluent of 10 m m citric acid–20 mm Na 2 HPO 4 aqueous buffer (pH 4.0)–CH 3 CN–CH 3 OH (50:45:5, v/v/v %). The calibration curves prepared with 1‐methyl‐3‐phenylpropylamine (MPPA) as an internal standard showed good linearity ( r = 0.999) with 0.36–0.83 ng/mL detection limit at a signal‐to‐noise ratio of 3. MDMA and MDA in rat whole blood could be monitored for 6 h after a single administration of MDMA (2.2 mg/kg, i.p.). The pharmacokinetic parameters for MDMA and MDA obtained by triplicate measurements were 426 ± 23 and 39 ± 6 ng/mL ( C max ), 20 ± 5 and 100 ± 10 min ( T max ), respectively. Copyright © 2006 John Wiley & Sons, Ltd.