A general screening and confirmation approach to the analysis of designer tryptamines and phenethylamines in blood and urine using GC-EI-MS and HPLC-electrospray-MS.
Journal of analytical toxicology – September 01, 2004
Source: PubMed
Summary
Identifying new designer drugs in the body poses a unique challenge for forensic science. A new approach effectively addresses this by providing reliable `detection` and `quantitation` in `blood` and `urine`. Researchers successfully employed `GC-EI-MS` to screen for various designer tryptamines and phenethylamines, demonstrating high sensitivity and accuracy. This method was successfully applied to real-world samples. Further confirmation and detailed `quantitation` of specific compounds were achieved using `HPLC-electrospray-MS`, which also identified key metabolic byproducts. This robust analytical framework significantly enhances the ability to identify these substances in biological samples.
Abstract
Recent additions of designer tryptamines and phenethylamines to the Drug Enforcement Administration's schedule of controlled substances necessitate analytical procedures for their detection and quantitation. As specific immunoassays are not currently available and cross-reactivities with existing assays are unknown, a screening method based on gas chromatography-mass spectrometry was developed. The method was capable of measuring the pentafluoropropionic derivatives of a-methyltryptamine (AMT), N,N-dimethyltryptamine (DMT), 4-bromo-2,5-dimethoxy-beta-phenethylamine (2CB), N,N-dipropyltryptamine (DPT), 2,5-dimethyl-4-N-propylthio-beta-phenethylamine (2C-T-7), and 5-methoxy-N,N-diisopropyltryptamine (5-MeO-DiPT). Separation was optimized to allow tentative identification of metabolites, which display common electron impact ionization fragmentation patterns. The screening method gave limits of detection between 5 and 10 ng/mL and demonstrated linearity between 50 and 1000 ng/mL. The method was successfully applied to blood and urine samples in suspected AMT intoxications. Confirmation of 5-MeO-DiPT in one of the subjects' urine was achieved using liquid chromatography-mass spectrometry (LC-MS). Quantitation by selected ion monitoring (SIM) yielded a urinary concentration of 229 ng/mL. The method was linear from 25 to 1500 ng/mL with a correlation coefficient of 0.995. The limit of detection was 5 ng/mL in urine on the LC-MS. Two additional peaks were observed and presumed to be metabolic products reported previously as 5-methoxy-N-isopropyltryptamine (5-MeO-iPT) and 5-methoxy-N,N-diisopropyltryptamine-N'-oxide (5-MeO-DiPT-N-oxide).