| Abstract
| - A novel approach was used to analyze street drugs inseized material without primary reference standards.Identification was performed by liquid chromatography/time-of-flight mass spectrometry (LC/TOFMS), essentiallybased on accurate mass determination using a targetlibrary of 735 exact monoisotopic masses. Quantificationwas carried out by liquid chromatography/chemiluminescence nitrogen detection (LC/CLND) with a singlesecondary standard (caffeine), utilizing the detector'sequimolar response to nitrogen. Sample preparationcomprised dilution, first with methanol and further withthe LC mobile phase. Altogether 21 seized drug sampleswere analyzed blind by the present method, and resultswere compared to accredited reference methods utilizingidentification by gas chromatography/mass spectrometryand quantification by gas chromatography or liquid chromatography. The 31 drug findings by LC/TOFMS comprised 19 different drugs-of-abuse, byproducts, and adulterants, including amphetamine and tryptamine designerdrugs, with one unresolved pair of compounds having anidentical mass. By the reference methods, 27 findingscould be confirmed, and among the four unconfirmedfindings, only 1 apparent false positive was found. In thequantitative analysis of 11 amphetamine, heroin, andcocaine findings, mean relative difference between theresults of LC/CLND and the reference methods was 11%(range 4.2−21%), without any observable bias. Meanrelative standard deviation for three parallel LC/CLNDresults was 6%. Results suggest that the present combination of LC/TOFMS and LC/CLND offers a simple solutionfor the analysis of scheduled and designer drugs in seizedmaterial, independent of the availability of primary reference standards.
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