Metoprolol is a lipophilic, cardioselective β-adrenergic blocking agent commercially available as a racemic compound. A normal phase high-performance liquid chromatographic method was developed to directly determine individual enantiomeric concentrations of metoprolol in human serum. Separation of the enantiomers was accomplished by a cellulose-tris(3,5-dimethylphenylcarbamate) chiral stationary phase. Metoprolol enantiomers were detected by means of fluorescence with excitation and emission wavelengths of 275 and 315 nm, respectively. Standard curves were linear over the concentration range 12.5-400 ng/ml for each enantiomer. Within-day coeffient of variation was <15% at all concentrations and the between-day coefficient of variation ranged from 4.1 to 11.2%. The limit of detection was determined to be 5 ng/ml for each enantiomer and the stereoselective resolution (α) of R- and S-metoprolol was 3.08. The assay was employed to determine enantiomeric serum concentrations of metoprolol in healthy male volunteers.
|Original language||English (US)|
|Number of pages||11|
|Journal||Journal of Chromatography B: Biomedical Sciences and Applications|
|State||Published - 1990|
Bibliographical noteFunding Information:
We thank our colleagues( Ciba-Geigy Ltd., Base&S witzerland) for their gift of the metoprolol enantiomersa nd Dr. William Elmquist and Ms. Shu-Hui Huang for their assistancei n the use of the weighting program. We also thank Dr. Cynthia Gross for her statisticalc onsultation and the American Association of Colleges of Pharmacy, University of Minnesota Graduate School Grant-in-Aid Program and the Ramsey Foundation for their contributions in support of this project.