A gas chromatography/resonance electron capture ionization mass spectrometry method was developed to quantify LSD and its metabolite N-demethyl-LSD in urine. The method achieved detection limits of 0.1 ng/mL for LSD and 0.2 ng/mL for N-demethyl-LSD, with linear calibration curves over a range of 0.5 to 20 ng/mL. The technique was applied to urine samples from human subjects administered known doses of LSD, demonstrating reliable identification and measurement of both compounds. The approach offers improved sensitivity and specificity for forensic and clinical detection of LSD use.
A method detects LSD in urine at concentrations as low as 0.5 ng/mL. After adding a deuterium-labeled internal standard, LSD is extracted from urine at pH 8 using n-butyl chloride, then converted to a trimethylsilyl derivative and measured by gas chromatography–mass spectrometry with selected ion monitoring. The procedure tracked LSD concentrations in urine for eight hours after two volunteers each took 70.5 micrograms of LSD orally. Results are compared with those from radioimmunoassay and high-performance liquid chromatography. The report also includes data on LSD stability in urine.