SOFT 2004 Meeting Abstracts - Society of Forensic Toxicologists

A46
A RAPID METHOD FOR THE ANALYSIS OF ATOMOXETINE IN BLOOD USING GCIMS
Mike K. Angier*, Russell 1. Lewis & Robert D. Johnson, Federal Aviation Administration, Civil Aerospace
Medical Institute, Bioaeuronautical Sciences Research Laboratory, P.O. Box 25082, Oklahoma City,
Oklahoma 73125
Atomoxetine is a selective norepinephrine reuptake inhibitor (SNRI) prescribed for the treatment of
attention deficitJhyperactivity disorder (ADHD). It is the first non-stimulant drug approved by the FDA for
the treatment of this disorder in both adults and children. Since its approval in November 2002, over two
million prescriptions have been filled. It has been estimated that 3% of the U.S. adult population may have
ADHD. A review of the current literature has identified no gas chromatographic/mass spectrometric
(GCIMS) methods for the detection of atomoxetine in the forensic toxicology setting. Therefore, our
laboratory developed a method for the identification and quantitation of atomoxetine in postmortem blood
using GCIMS. This procedure incorporates a Varian Bond Elut® Certify solid phase extraction (SPE)
followed by derivitization with pentafluoropropionic anhydride (pFPA). Derivitization of atomoxetine
with PFPA, although not required for the GC/MS analysis of this compound, affords both superior linearity
and sensitivity over the non-derivatized compound. The method described is highly selective and sensitive,
having a limit of detection of 1 ng/mL for atomoxetine. Atomoxetine was found to have a linear dynamic
range of 3 - 800 ng/mL on a calibration curve weighted by a factor of l/x. The SPE provided an efficient
sample extraction yielding recoveries of 40 ± 3% and 51 ± 4% at 25 and 250 ng/mL (n=5 for each group).
Furthermore, the developed procedure provided superb accuracy and precision. This procedure showed
intra-day (within day) relative errors of::; 5% and relative standard deviations (RSD) within 2% for both the
25 ng/mL and 250 ng/mL control groups (n=5 for each group). Using whole blood controls stored at 4°C
the inter-day (between day) relative errors for the 25 ng/mL control group were 9%, 10% and 3% for days
2,3 and 7, respectively (n:=:5). The relative errors for the 250 ng/mL control group were 6%, 3% and 4%
for days 2, 3 and 7, respectively (n=5). The RSDs were all < 5% for both control groups over the 7-day
period. Based on the day 7 results, it is clear that atomoxetine is stable in blood stored at 4°C for at least
one week. The method developed proved to be rapid, reliable and sensitive for the identification and
quantitation ofatomoxetine in blood.
Key Words: Atomoxetine, SNRI, Forensic Toxicology
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