Kenneth S. Webb

2 papers in the library · 65 citations · publishing 1996-1999

Papers

The Analysis of Lysergide (LSD): The Development of Novel Enzyme Immunoassay and Immunoaffinity Extraction Procedures Together with an HPLC-MS Confirmation Procedure

Journal of Forensic Sciences November 1, 1996 Kenneth S. Webb, Pb Baker, N. P. Cassells et al. 42 citations

A 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.

DOI: 10.1520/jfs14029j Immunoassay Extraction chemistry High-performance liquid chromatography Medicine +1

The Determination of Lysergide (LSD) in Urine by High-Performance Liquid Chromatography-Isotope Dilution Mass Spectrometry (IDMS)

Journal of Forensic Sciences March 1, 1999 Sa White, A. Kidd, Kenneth S. Webb 23 citations

Isotope dilution mass spectrometry (IDMS) improves the forensic confirmation of lysergic acid diethylamide (LSD) in urine when using liquid chromatography–mass spectrometry (LC-MS). Using a deuterated analog of LSD as an internal standard offers advantages over methysergide. The method achieves a limit of quantification (LOQ) of 0.5 ng/mL, meeting the laboratory's forensic requirement, and can be improved to 0.1 ng/mL under some circumstances. It is linear up to 10 ng/mL LSD in urine and has been validated for accuracy and precision. The study also compares electrospray mass spectra of LSD, LSD-d3, and methysergide, and discusses suitable ions for selected ion monitoring.

DOI: 10.1520/jfs14467j Lysergic acid diethylamide Isotope dilution Chemistry Urine +3