SOFT 2004 Meeting Abstracts - Society of Forensic Toxicologists

M42
A MIXED MODE SOLID-PHASE EXTRACTION METHOD FOR THE LC/MS
DETERMINATION OF DRUGS OF ABUSE IN PRESERVED SALIVA
Kevin M. Jenkins, Michael S. Young*: Waters Corporation, 34 Maple Street, Milford, MA
Saliva is a less invasive alternative to urine or blood in forensics analysis for drugs of abuse. Because drug
residues are typically less concentrated in saliva than in other biological fluids such as blood or urine,
quantification limits for saliva samples must be considerably lower than for urine, in the low nglmL range.
Compared with GCIMS, LCIMS is a simpler analytical approach requiring no derivatization. However, the
saliva collection fluid contains ingredients (stabilizers and preservatives) that present some interference
problems for LCIMS. A mixed-mode (cation-exchange) SPE cartridge, Oasis MCX, provided effective
cleanup suitable for LCIMS determination of basic drugs of abuse in preserved saliva. The drugs studied
were cocaine, codeine, morphine, amphetamine, methamphetamine, ecstasy (MDMA) and phencyclidine
(PCP). MDMA-d5 was used as an internal standard. Calibration was accomplished in the range from 5 to
250 ng/mL. Correlation coefficients (r2) for all constituents were better than 0.998. Reproducibility for all
constituents was better than 10 % (RSD) for 6 replicate samples fortified at the 10 nglmL and 50 nglmL
levels. Recovery was better than 85 % for all constituents.
Keywords: Saliva, LCIMS, Drugs of Abuse
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