TABLE 1

Study drugs, reference standard provider, and analytical method information

Study drugs: caffeine, 100-mg tablets (GlaxoSmithKline, Uxbridge, Middlesex, UK); bupropion, 150-mg extended release tablets (Watson Pharmaceuticals, Corona, CA); tolbutamide, 500-mg tablets (Mylan, Pittsburgh, PA); and dextromethorphan, 15-mg Robitussin Cough Gels (Wyeth Consumer Healthcare, New York, NY).

Reference StandardsSupplier InformationAnalytical MethodUPLC/MS/MS Detection Parameters: m/z Transition, Cone Voltage, Collision Energy
CaffeineCerilliant (Round Rock, TX)UPLC/MS/MS and HPLC/UV195.1 < 137.9, 15, 20
1-Methyl uric acidSigma-Aldrich (St. Louis, MO)HPLC/UVN.A.
1,7-Dimethyl uric acidSigma-AldrichHPLC/UVN.A.
1-Methyl xanthineSigma-AldrichHPLC/UVN.A.
AAMUSigma-AldrichHPLC/UVN.A.
BupropionCerilliantUPLC/MS/MS240.0 < 184.0, 20, 20
4-OH-BUPCerilliantUPLC/MS/MS256.0 < 238.0, 17, 20
TolbutamideSigma-AldrichUPLC/MS/MS271.1 < 172.0, 25, 10
4-OH TOLBSigma-AldrichUPLC/MS/MS287.2 < 188.0, 25, 10
Carboxy tolbutamideSigma-AldrichUPLC/MS/MS301.0 < 201.9, 20, 10
DextromethorphanSigma-AldrichUPLC/MS/MS272.3 < 215.2, 40, 22
DextrorphanSigma-AldrichUPLC/MS/MS258.2 < 201.2, 45, 22
3-Methoxy morphinanSigma-AldrichUPLC/MS/MS258.1 < 201.2, 37, 35
Internal standards for quantification
    d4-MidazolamCerilliantUPLC/MS/MS330.0 < 295.2, 40, 27
    d4-OH midazolamCerilliantUPLC/MS/MS346.0 < 328.2, 40, 22
    [13C]CaffeineToronto Research Chemicals Inc. (North York, ON, Canada)UPLC/MS/MS198.1 < 139.9, 15, 20
    ChlorpropamideSigma-AldrichUPLC/MS/MS277.0 < 174.9, 25, 15
    7-β hydroxy propyl theophyllineSigma-AldrichHPLC/UVN.A.
  • N.A., not applicable.