title: A rapid and convenient LC/MS method for routine identification of methamphetamine/dimethylamphetamine and their metabolites in urine.
abstract: A rapid and sensitive LC/MS method was developed for the simultaneous analysis of N,N-dimethylamphetamine (DMA), N,N-dimethylamphetamine N-oxide (DMANO), methylamphetamine (MA) and amphetamine (A) in urine samples. Employing an Alltech C18 column for solid phase extraction followed by LC/MS analysis using an Alltech Platinum EPS C18 column with a mixture of ammonium formate (0.01 M, pH 3) and acetonitrile (77:23, v/v) as mobile phase at a flow rate of 0.2 mL/min, simultaneous identification and quantitation of A, MA, DMA and DMANO in urine can be achieved using a 5-min chromatographic run. The calibration ranges were 0.10-3.0 micro g/mL for DMANO, 0.05-3.0 micro g/mL for DMA and 0.05-5.0 micro g/mL for both MA and A. The intra-, inter-day precision and accuracy for all analytes, spiked at three different concentrations in quality control samples, were in the ranges of 1.7-8.6, 4.1-10.0, -11.6 to 12.9%, respectively. The newly developed method was applied to the analysis of urine samples obtained from 118 suspected MA/DMA abusers, with the presence of MA confirmed in their urine samples under the drug-use surveillance program. Of these 118 samples, 43 were found to contain DMANO and 11 with both DMANO and DMA.
authors.affiliation: Forensic Science Division, Government Laboratory, Homantin Government Offices, Homantin, Hong Kong SAR, China. wccheng@govtlab.gov.hk
authors.forename: Wing-Chi
authors.initials: WC
authors.lastname: Cheng
authors.forename: Vincent King-Kuen
authors.initials: VK
authors.lastname: Mok
authors.forename: Ka-Keung
authors.initials: KK
authors.lastname: Chan
authors.forename: Ava Fung-Man
authors.initials: AF
authors.lastname: Li
mesh_terms: D000661:Amphetamine / Q000652:urine*; D019969:Amphetamine-Related Disorders / Q000652:urine*; D002853:Chromatography, Liquid / Q000379:methods; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods*; D008694:Methamphetamine / Q000031:analogs & derivatives / Q000652:urine; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D015813:Substance Abuse Detection / Q000379:methods*
chemical_list: D008694:Methamphetamine; D000661:Amphetamine; C003714:dimethylamphetamine