| Objective | To determine if a blood sample contains illicit drugs (from a short list of possibilities). |
| Sample | Simulated blood plasma with added illicit drug at a concentration of about 0.30 µg/mL. Prepare a fresh sample the day of the testing; the sample is not stable for more than a couple of days, even when stored in the refrigerator. The drug is chosen from a short list, provided to the students. Drug standards may be purchased without a DEA license (e.g. from Sigma-Aldrich) . |
| Reagents | Drug standard (Sigma-Aldrich); methanol; 0.050 M, pH 6.0 phosphate buffer; 0.10 M HCl; 80:18:2 mixture of ethyl acetate:methanol:ammonium hydroxide |
Standard Reference Material | None |
| Method | Solid phase extraction ; gas chromatography - mass spectrometry |
| Special equipment | Capillary gas chromatograph-mass spectrometer with mid-polar column (e.g. DB-5, phenyl methyl silane, 30 m x 0.25 mm x 0.25 µm); 10-µL syringe; 2-mL chromatography vials with screw caps; 3-mL, mixed-mode (C8 & strong cation exchanger) solid phase extraction (SPE) cartridges (e.g. Strata Screen C from Phenomenex); vacuum manifold; aluminum heating block and supply of nitrogen gas for evaporating solvents |
| Procedure | For instructor (detailed) ; For student (brief) |
| Typical results | Total ion chromatogram of 0.50 µg/mL drug sample (cocaine) processed by SPE; 5µL injection of SPE eluate at 20:1 split; 1 mL/min helium flow; temperature programmed separation; ion trap mass analyzer. Mass spectrum of suspected drug (cocaine) from chromatogram above. Result of library search of suspected cocaine spectrum. |
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