| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 96446 | Forensic Science International | 2012 | 4 Pages |
The aim of the present investigations was to find markers for differentiating between the consumption of illegal cannabis products and legal medication containing fully synthetic Δ9-tetrahydrocannabinol (Δ9-THC), e.g., Marinol® capsules. Δ9-Tetrahydrocannabinolic acid A (Δ9-THCA-A) and Δ9-tetrahydrocannabivarinic acid A (Δ9-THCVA-A) were taken into consideration for analysis, because these substances are the precursors of Δ9-THC and Δ9-tetrahydrocannabivarin (Δ9-THCV) in plant material of Cannabis sativa and are not contained in medical THC formulations. Whereas Δ9-THCA-A is an already well investigated substance, there is little analytical data on Δ9-THCVA-A.The reason for the presented investigations was a case in which a man was tested positive for Δ9-THC during a routine traffic control claiming that the positive serum sample resulted from the intake of a THC medication (Marinol®) and not from consuming illegal cannabis products.Sample preparation consisted of a protein precipitation with acetonitrile. Analysis was carried out on a Thermo Fisher LCQ Deca ion trap LC–MS–MS-system using electron spray ionization (ESI) in negative mode. MS2- and MS3-full scan spectra were recorded for Δ9-THCA-A and Δ9-THCVA-A starting from [M−H]−. Reference spectra were obtained by measuring a Δ9-THCA-A reference solution and an ethanolic cannabis extract for Δ9-THCVA-A as there is no reference material for this cannabinoid available on the market yet.Main transitions for Δ9-THCA-A were m/z 357 → 313 and 339 in the MS2-spectrum and m/z 313 → 245 and 191 in the MS3-spectrum. Fragmentation pattern of Δ9-THCVA-A was identical with a difference of 28 amu less for the precursor ion as well as the fragments due to a shorter alkyl side chain in the molecule (MS2: m/z 329 → 285 and 311; MS3: m/z 285 → 217 and 163).The two plant cannabinoids Δ9-THCA-A and Δ9-THCVA-A could be detected in the serum sample by LC–MS–MS which proved the intake of illegal cannabis products derived from plant material of C. sativa in the described case.
