title: A sensitive assay of metoprolol and its major metabolite alpha-hydroxy metoprolol in human plasma and determination of dextromethorphan and its metabolite dextrorphan in urine with high performance liquid chromatography and fluorometric detection.
abstract: A reverse-phase High Performance Liquid Chromatographic (HPLC) method was developed for the analysis of metoprolol in the large number of human plasma samples obtained in in vitro-in vivo correlations (IVIVC) and bioavailability studies of extended release formulations of metoprolol tartrate. The metabolite, alpha-hydroxy metoprolol (OH-met), could also be quantified. The analytes were extracted from the plasma using solid phase columns, separated on a C-4 analytical column followed by fluorimetric detection. The linearity, precision, accuracy, stability, selectivity and ruggedness were validated for the concentration ranges of 1-400 ng ml-1 for metoprolol and 0.5-200 ng ml-1 for OH-met. The same chromatographic conditions were slightly modified to quantify dextromethorphan and its metabolite dextrorphan in urine in the concentration range 0.052-0.05 microgram ml-1 as a method for screening for fast metabolizers.
authors.affiliation: Department of Pharmaceutical Sciences, University of Maryland at Baltimore 21201-1082, USA.
authors.forename: B
authors.initials: B
authors.lastname: Mistry
authors.forename: J
authors.initials: J
authors.lastname: Leslie
authors.forename: N E
authors.initials: NE
authors.lastname: Eddington
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000097:blood*; D000996:Antitussive Agents / Q000652:urine*; D002851:Chromatography, High Pressure Liquid; D003915:Dextromethorphan / Q000652:urine*; D003917:Dextrorphan / Q000652:urine*; D006801:Humans; D007202:Indicators and Reagents; D008790:Metoprolol / Q000031:analogs & derivatives* / Q000097:blood; D018696:Neuroprotective Agents / Q000652:urine*; D011786:Quality Control; D012015:Reference Standards; D015203:Reproducibility of Results; D013050:Spectrometry, Fluorescence
chemical_list: D000319:Adrenergic beta-Antagonists; D000996:Antitussive Agents; D007202:Indicators and Reagents; D018696:Neuroprotective Agents; D003917:Dextrorphan; C029504:alpha-hydroxymetoprolol; D003915:Dextromethorphan; D008790:Metoprolol