The Analysis of Lysergide (LSD): The Development of Novel Enzyme Immunoassay and Immunoaffinity Extraction Procedures Together with an HPLC-MS Confirmation Procedure
Kenneth S. Webb, Pb Baker, N. P. Cassells, James B. Francis, D.e. Johnston, Steve Lancaster, P.s.b. Minty, G. D. Reed, Sa White
Journal of Forensic Sciences November 1, 1996 DOI: 10.1520/jfs14029j via OpenAlex
Summary
AI-generated from the abstractA forensic procedure for detecting lysergide (LSD) in urine uses a novel enzyme immunoassay (EIA) and immunoaffinity extraction alongside an established radioimmunoassay (RIA). Initial screening is followed by quantitative estimation via high-performance liquid chromatography with fluorescence detection after solid phase extraction. Final confirmation and quantitation, without derivatization, uses HPLC with electrospray ionization mass spectrometry and methysergide as an internal standard. The detection limit is 0.5 ng/mL. A blind trial confirmed the results. The study discusses internal standard choice, LSD's photo-sensitivity, and shows no interferants among a wide range of compounds tested. Comparisons are made between extraction and screening methods.
Study at a glance
| Characteristics | Method development and validation Peer reviewed |
|---|---|
| Population | Urine samples |
| Keywords | Immunoassay Extraction chemistry High-performance liquid chromatography Medicine Antibody |
| Citations | 42 |
| Key finding | A novel enzyme immunoassay and immunoaffinity extraction procedure, combined with HPLC-fluorescence and HPLC-ESI-MS, reliably screens and confirms LSD in urine at a detection limit of 0.5 ng/mL with no interferants from a wide range of compounds. |
Abstract
Abstract A forensic procedure for the screening and confirmation of the presence of lysergide (lysergic acid diethylamide, LSD) in urine is described together with the evaluation of a novel enzyme immunoassay (EIA) and immunoaffinity extraction procedure. Following initial screening using either an established radioimmunoassay (RIA) or a novel EIA procedure, a quantitative estimate is established using a conventional high performance liquid chromatography-fluorescence (HPLC) technique following solid phase extraction. Final confirmation and quantitation, without derivatization, is established using HPLC in combination with electrospray ionization (ESI) mass spectrometry using methysergide as an internal standard. The detection limit of LSD in urine is 0.5 ng/mL. A blind trial confirmed the validity of the results. The choice of internal standard is discussed. Consideration is given to the photo-sensitivity of LSD solutions. A study of potential interferants in the HPLC-MS confirmation of LSD is presented and shows that for the wide range of compounds studied, there are none that would interfere with this confirmation technique. A comparison is shown between solid phase and immunoaffinity extraction/clean up procedures, and between RIA and EIA screening procedures.