Applications of liquid chromatography-tandem mass spectrometry in drug andbiomedical analyses

Background: Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is on e of the major tools for bioanalytical works. These instruments can be used for quantitative determination of plasma samples in pharmacokinetic studie s. LC-MS/MS techniques frequently provide specific, selective and sensitive quantitative results often with reduced sample preparation and analysis ti me relative to other commonly employed techniques. Methods: The application s of these instruments include analysis of nine corticosteroids illegally a dulterated in traditional Chinese medicines, identification of drug metabol ites of roxithromycin, propafenone and some glucuronide conjugates and the quantitative determination of plasma samples containing amlodipine, nitrend ipine, flupirtine and their major metabolites. Conclusions: LCQ is ideally suited for the rapid identification of metabolites because it provides on-l ine LC/MSn capability, enabling multiple MS stages to obtain the maximum am ount of structural information, while TSQ provides excellent precise and ac curate results for quantitative assays at very low detection limits. (C) 20 01 Elsevier Science B.V. All tights reserved.