title: Simultaneous gas chromatographic determination of methamphetamine, amphetamine and their p-hydroxylated metabolites in plasma and urine.
abstract: We report a method for the simultaneous determination of methamphetamine, amphetamine and their hydroxylated metabolites in plasma and urine samples using a GC-NPD system. The analytical procedures are: (1) adjust the sample to pH 11.5 with bicarbonate buffer, saturate with NaCl and extract with acetate; (2) back-extract the amines in the ethyl acetate fraction with 0.1 M HCl; (3) adjust the pH of the acid fraction to 11.5 and follow by extraction in ethyl acetate; (4) reduce the volume of ethyl acetate under nitrogen and derivatize the concentrate with trifluoroacetic anhydride or heptafluorobutyric anhydride before the GC analysis. The derivatives were separated on a GC-NPD system equipped with a HP-5 column of 25 m x 0.32 m I.D. and a 0.52 micron film of 5% phenylmethylsilicone. The detection limit (taking a signal-to-noise ratio of 2) of heptafluorobutyl derivatives of methamphetamine and its metabolites in plasma and the trifluoroacetyl derivatives in urine was 1 ng/ml (22 pg on column). The limit of quantitation of the heptafluorobutyl derivatives in the plasma was 1 ng/ml (22 pg on column), and that of the trifluoroacetyl derivatives in urine was 20 ng/ml (73 pg on column). The between-day variation was from 0.9 to 17.4% and within-day variation from 0.9 to 8.3%. This method was used successfully in the quantitative determination of methamphetamine and its p-hydroxylated metabolites in the plasma and urine of human subjects.
authors.affiliation: Biobehavioral Research Department, Addiction Research Foundation of Ontario, Toronto, Canada.
authors.forename: S
authors.initials: S
authors.lastname: Cheung
authors.forename: H
authors.initials: H
authors.lastname: Nolte
authors.forename: S V
authors.initials: SV
authors.lastname: Otton
authors.forename: R F
authors.initials: RF
authors.lastname: Tyndale
authors.forename: P H
authors.initials: PH
authors.lastname: Wu
authors.forename: E M
authors.initials: EM
authors.lastname: Sellers
mesh_terms: D000661:Amphetamine / Q000097:blood* / Q000378:metabolism / Q000652:urine*; D000697:Central Nervous System Stimulants / Q000097:blood* / Q000378:metabolism / Q000652:urine*; D002849:Chromatography, Gas; D006801:Humans; D006900:Hydroxylation; D008694:Methamphetamine / Q000097:blood* / Q000378:metabolism / Q000652:urine*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D000697:Central Nervous System Stimulants; D008694:Methamphetamine; D000661:Amphetamine