AI-64310-CRFT

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Determination of LSD and Its Metabolites
in Human Biological Samples by Liquid
Chromatography–Tandem Mass Spectrometry
François-Ludovic Sauvage1, Pierre Marquet 1,2
1Department of Pharmacology-Toxicology, University Hospital, Limoges, France.
2Laboratory of Pharmacology, Faculty of Medicine, University of Limoges, France.
Application
Note: 383
Key Words
• TSQ Quantum
• Drugs of Abuse
• Forensic
analysis
• LC-MS/MS
• LSD (Lysergic
acid diethy-
lamide
• LSD metabolites
• Toxicology
Introduction
Lysergic acid diethylamide (LSD) is a very potent
hallucinogenic drug involving, particularly, behavioral
disorders and is also extensively metabolized in man.
Moreover, LSD and its major metabolites are present
at low concentration in biological fluids, such as whole
blood or urine. Identification and quantitation of such
compounds for forensic use necessitate a sensitive and
specific method. This study aims to describe a method
using liquid chromatography/tandem mass spectrometry
and permitting to quantify LSD and its metabolites at low
concentrations.
Goal
The goal of this study was to identify and quantify LSD,
iso-LSD, nor-LSD, nor-iso-LSD and 2-oxo-3-hydroxy-LSD
in biological matrices. This report demonstrates the use
of the TSQ Quantum for this application.
Experimental Conditions/Methods
Chemicals and Reagents
Lysergic acid diethylamide (LSD), d 3-LSD (internal
standard), 2-oxo-3-hydroxy-LSD, iso-LSD, nor-LSD were
purchased from Cerilliant (Austin, TX, USA). Ammonium
formate and formic acid (>99 % pure) were purchased
from Sigma. All reagents and solvents used in the extrac-
tion procedures were of analytical grade.
Sample Preparation
To 2 mL of serum, urine or whole blood content were
added 100 µL of a 0.025 µg/mL aqueous solution of
d 3-LSD (Internal Standard), 1 mL of a solution of pH 9.50
carbonate buffer and 8 mL of dichloromethane-isopropanol
(95:5 by volume). The tubes were vortex-mixed and
shaken on an oscillatory mixer. After centrifugation at
3,400 g for 5 min, the organic phase was poured in a
conical glass tube and evaporated under a stream of
nitrogen at 37°C. The dried extracts were reconstituted
in 25 µL of acetonitrile : pH 3.0, 2 mmol/L ammonium
formate (30:70 by volume) and 10 µL were injected into
the chromatographic system.
Instrumentation Methods
HPLC Conditions
The chromatographic system consisted of a Shimadzu
10ADvp micro-flow rate, high-pressure gradient pumping
system with a Rheodyne® Model 7725 injection valve
equipped with a 5 µL internal loop. A C18, 5 µm (50 × 2.1
mm) column, maintained at 25°C, was used with a linear
gradient of mobile phase A (pH 3.0, 2 mmol/L ammonium
formate) and mobile phase B (ac 3.0, 2 mmol/L
ammonium formate [90:10; v/v]), flow rate of 200 µL/min,
programmed as follows: 0-1.5 min, 5% B; 1.5-9 min, 5 to
50% B; 9-10 min, 50 to 90% B; 10-10.5 min, decrease
from 90 to 5% B; 10.5-13 min, equilibration with 5% B.
MS Conditions
Mass Spectrometer: Thermo Scientific TSQ Quantum
Source: ESI mode
Ion Polarity: Positive
Spray Voltage: 4000 V
Sheath/Auxiliary gas: Nitrogen
Sheath gas pressure: 25 (arbitrary units)
Auxiliary gas pressure: 15 (arbitrary units)
Ion transfer tube temperature: 250°C
Scan type: SRM
Collision gas: Argon
Collision gas pressure: 1.5 mTorr
SRM Conditions
Settings were optimized by infusing at 5 µL/min a 1 µg/L
solution containing the studied compound in acetonitrile:
pH 3.0, 2 mmol/L ammonium formate (30:70, by volume).
The structure of these compounds is shown in Figure 1.