LC-MS analysis of trimethoxyamphetamine designer drugs (TMA series) from urine samples

A sensitive liquid chromatography–mass spectrometric (LC–MS) method for quantification of an active
psychedelic hallucinogenic drugs (trimethoxyamphetamines) in human urine after solid-phase extraction
(SPE) with C18 cartridge was developed and validated. Chromatographic separation was achieved
on reversed-phase Phenomenex 3.0m Polar Plus column (150mm×2.1mm) with acetonitrile −0.2%
acetic acid as mobile-phase and the step gradient elution resulted in a total run time of about 20 min. The
analytes were detected by using an electrospray positive ionization mass spectrometry in selected ion
monitoring (SIM) mode. In the evaluated concentration range (10–200 ng/mL) (R2 ≥0.998) a good linear
relationship was obtained. The lower limits of detection (LLODs) and quantification (LLOQs) ranged from
4.26 to 9.12 ng/mL and from 13.18 to 29.22 ng/mL, respectively. Average recoveries ranged from 68.52
to 97.90% in urine at the concentrations of 25, 50 and 100 ng/mL. Intra- and inter-day relative standard
deviations were 3.70–10.77% and 7.63–12.94%, respectively. This LC–MS method proved to be robust and
reliable, and suitable for the use as a confirmation method in clinical urine drug testing.