LC-MS Analysis of Human Urine Specimens for 2-Oxo-3-Hydroxy LSD: Method Validation for Potential Interferants and Stability Study of 2-Oxo-3-Hydroxy LSD Under Various Storage Conditions

A major metabolite of LSD, 2-oxo-3-hydroxy lysergic acid diethylamide (O-H-LSD), is a superior marker for identifying LSD use because it appears in urine at concentrations 16 to 43 times higher than LSD itself. Testing a wide range of chemically similar compounds, over-the-counter products, prescription drugs, and other drugs of abuse showed none interfered with detecting O-H-LSD. The metabolite remained stable under refrigerated and frozen conditions within normal urine pH (4.6-8.4), but significant loss occurred at room temperature or higher (24-50°C). These findings support the forensic reliability of liquid chromatography-mass spectrometry for detecting LSD use via O-H-LSD.

Study at a glance

Abstract

2-Oxo-3-hydroxy lysergic acid diethylamide (O-H-LSD), a major LSD metabolite, has previously been demonstrated to be a superior marker for identifying LSD use compared with the parent drug, LSD. Specifically, O-H-LSD analyzed using liquid chromatography-mass spectrometry has been reported to be present in urine at concentrations 16 to 43 times greater than LSD. To further support forensic application of this procedure, the specificity of the assay was assessed using compounds that have structural and chemical properties similar to O-H-LSD, common over-the-counter products, prescription drugs and some of their metabolites, and other drugs of abuse. Of the wide range of compounds studied, none were found to interfere with the detection of O-H-LSD or the internal standard 2-oxo-3-hydroxy lysergic acid methyl propylamide. The stability of O-H-LSD was investigated from 0 to 9 days at various temperatures, pH conditions, and exposures to fluorescent light. Additionally, the effect of long-term frozen storage and pH was investigated from 0 to 60 days. There was no significant loss of O-H-LSD under both refrigerated and frozen conditions within the normal human physiological pH range of urine (4.6-8.4). However, significant loss of O-H-LSD was observed in samples prepared at pH 4.6-8.4 and stored at room temperature or higher (24-50 degrees C).