Determination of Methamphetamine Enantiomer Composition in Human Hair Using Clean Screen® DAU SPE Columns.
One of the issues that face forensic toxicologists is the analysis of chiral drugs especially within the amphetamine type substances (ATS). The R enantiomer of methamphetamine is an active ingredient of Vicks inhaler, and a metabolite of some legitimate medications such as Selegiline for anti-Parkinson’s treatment. The S enantiomer of methamphetamine is a schedule II controlled substance, which can be prescribed for medical use and has high potential for abuse. The enantiomeric ratio determination of the two is essential to discriminate between legal versus illicit use in methamphetamine-positive cases. Typically, chromatographic analysis is performed on expensive chiral GC/LC columns or using a chiral derivatizing reagent for GC-MS.
In a recent paper by I. Shu et al., published in the prestigious Journal of Chromatography B ((2016) 1028:145), methamphetamine was extracted using UCT’s flagship sorbent Clean Screen® DAU from hair samples. After pulverization and acid digestion, the samples were extracted using ZSDAU020 Solid Phase Extraction columns, evaporated, and derivatized with Marfey’s reagent. This permitted chiral analysis to be performed on a non-chiral LC column. By executing an efficient sample clean-up and concentrating the extract, it allowed for the detection of the analytes in question at the concentrations normally encountered in hair samples. The Society of Hair Testing (SoHT) recommends 200 pg/mg methamphetamine cut-off in hair to identify use, whereas Substance Abuse and Mental Health Services Administration (SAMHSA) proposed cut-off concentrations of 300 pg/mg and for hair, 250 ng/mL in urine. When analysts require high quality, clean, reproducible extracts for analysis, they turn to CleanScreen® DAU columns.
