Examination of Firearms Review: 2007 to 2010 - Interpol

urine [408]. To overcome matrix effects, a standard additions calibration
method was applied. The linear range was 0.25-2.5 µg/mL for both methods. A
method for the simultaneous detection of bovine, porcine and human insulins,
as well as the synthetic analogues Humalog (Lilly) and Novolog (Novo Nordisk)
in equine plasma, capable of detecting at 0.05 ng/mL, was described [409].
Administration studies of levamisole in horses were carried out using two
different levamisole preparations. Aminorex and rexamino, in addition to
levamisole and 4-phenyl-2-imidazolidinone, were detected in
post-administration urine and plasma samples [410]. It has been established
unequivocally that the normal use of levamisole products in horses can lead to
the presence of aminorex, rexamino, and 4-phenyl-2-imidazolidinone in their
urine and blood samples. A direct injection method was developed and
validated for the quantification and identification of salicylic acid by
LC-QTOFMS after the horse urine samples was 900-fold diluted, and the
internal standard (4-methylsalicylic acid) was added [411]. The intra- and
inter-assay precisions of salicylic acid in horse urine were better than 2.5% and
2.8%, respectively, with accuracy better than 3.3% deviation. A method for
differentiation and identification of rhEPO and DPO in equine plasma by
LC-MS/MS was reported [412]. The method involved analyte extraction and
enrichment by immunoaffinity separation with anti-rhEPO antibodies, dual
digestion by trypsin and peptide-N-glycosidase F (PNGase F), and analysis by
LC-MS/MS, with LODs of 0.05 ng/mL for DPO and 0.1 ng/mL for rhEPO.
3.4 Alternative Specimens
The use of alternative specimens in the field of toxicology was first described in
1979, when hair analysis was used to document chronic drug exposure. Since
then, 'alternative' samples such as oral fluid, hair, and sweat have gained
tremendous attention, and a large number of papers have been published.
'Alternative' specimens present a number of advantages over 'traditional'
samples (e.g., blood, urine, and tissues), namely the facts that their collection
is non-invasive, their adulteration is difficult, and they may allow suitable
windows of detection for certain drugs. The main disadvantage is that drugs
may be present in very low concentrations, and there are limited clinical
studies to aid in results interpretation. A literature review on the use of
alternative specimens, with special focus on the main analytical and
chromatographic problems for the analysis of these specimens, was presented;
the review included discussion on their advantages and disadvantages over
traditional samples in documenting drug exposure [413].
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