Optimization of separation and online sample concentration of N,N‐dimethyltryptamine and related compounds using MEKC

Optimal separation and online concentration methods for nine tryptamines, including DMT, AMT, and 5-MeO-DMT, were developed using micellar electrokinetic chromatography with UV detection. Limits of detection ranged from 1.0 to 1.8 μg/mL with standard MEKC, improved to 2.2–8.0 ng/mL using sweeping-MEKC, and further to 1.3–2.7 ng/mL using cation-selective exhaustive injection-sweep-MEKC. The migration order of the tryptamines was determined. A spiked human urine sample containing DMT was successfully analyzed, demonstrating practical applicability for drug testing.

Study at a glance

Abstract

Abstract The optimal separation conditions and online sample concentration for N , N ‐dimethyltryptamine (DMT) and related compounds, including α‐methyltryptamine (AMT), 5‐methoxy‐AMT (5‐MeO‐AMT), N , N ‐diethyltryptamine (DET), N , N ‐dipropyltryptamine (DPT), N , N ‐dibutyltryptamine (DBT), N , N ‐diisopropyltryptamine (DiPT), 5‐methoxy‐DMT (5‐MeO‐DMT), and 5‐methoxy‐ N , N ‐DiPT (5‐MeO‐DiPT), using micellar EKC (MEKC) with UV‐absorbance detection are described. The LODs (S/N = 3) for MEKC ranged from 1.0 ˜ 1.8 μg/mL. Use of online sample concentration methods, including sweeping‐MEKC and cation‐selective exhaustive injection‐sweep‐MEKC (CSEI‐sweep‐MEKC) improved the LODs to 2.2 ˜ 8.0 ng/mL and 1.3 ˜ 2.7 ng/mL, respectively. In addition, the order of migration of the nine tryptamines was investigated. A urine sample, obtained by spiking urine collected from a human volunteer with DMT, was also successfully examined.