A fast and reliable UPLC-MS/MS method was developed and validated for measuring dimethyltryptamine (DMT) in hair samples. The method, which pulverizes 20-milligram hair samples with methanol below 4 °C, achieved a lower limit of quantitation of 3 pg/mg and a calibration curve with R² = 0.992. Intraday and interday precision (RSD < 15%) and accuracy (92-113%) were acceptable, and dilution integrity was confirmed. Applied to 28 forensic cases, DMT concentrations ranged from 3 to 1109 pg/mg.
A rapid UHPLC-MS/MS method was developed to screen 16 tryptamines in hair samples. Twenty milligrams of hair were pulverized and processed, achieving limits of detection from 0.1 to 20 pg/mg and quantitation from 3 to 50 pg/mg. The method was applied to 191 hair samples from suspected tryptamine users; 77 tested positive for 5-MeO-DiPT, while the other 114 showed none of the targeted tryptamines or metabolites. In 34 samples, 5-MeO-DiPT and its metabolites 5-MeO-NiPT, 5-OH-DiPT, and 4-OH-DiPT were detected together. The method demonstrated good accuracy (91-114%), precision, and recovery (85-115%), making it suitable for forensic analysis of tryptamine use.