Forensic analysis of eleven cyclic antidepressants in human biological samples using a new reversed-phase chromatographic column of 2 mu m porous microspherical silica gel

A high-performance liquid chromatographic method has been developed for the forensic analysis of eleven frequently used cyclic antidepressant drugs (ADSs) (amitriptyline, amoxapine, clomipramine, desipramine, dosulepine, doxepin, imipramine, maprotiline, melitracen, mianserine and nortriptyline) using a recently developed reversed-phase column with 2 mu m particles for the analysis of biological samples. The separation was carried out using two different C-8 reversed-phase columns (column 1: 100 mmx4.6 mm LD., particle size 2 mu m, TSK gel Super-Octyl; column 2: 100 mmx4.6 mm LD., particle size 5 mu m, Hypersil MOS-C-8) for comparison. The mobile phase was composed of methanol-20 mM KH2PO4 (pH 7) (60:40, v/v) and the flow-rate was 0.6 ml/min for both columns. The absorbance of the eluent was monitored at 254 nm. When the eleven drugs were determined, the sensitivity with the 2 mu m particles was about five times greater than with the 5 mu m particles. Retention times on column 1 were shorter than those on column 2. These results show that the new ODS column packing with a particle size of 2 mu m gives higher sensitivity and a shorter analysis time than the conventional ODS column packing when applied to the analysis of biological samples.