Assay of metoprolol and alpha-hydroxymetoprolol in human urine by reversed-phase liquid chromatography with direct-injection
Abstract
AIM: To develop an HPLC method with direct injection for the simultaneous determination of metoprolol (M) and alpha-hydroxymetoprolol (HM) in human urine.
METHODS: Urine (200 microliters) was diluted with eluate and injected into the chromatograph. Samples were separated on an ODS column by isocratic binary elution and monitored by fluorescence detection.
RESULTS: No potential interfering peaks were identified. M and HM gave rapid elution and baseline resolution. The linear curves of both analytes ranged between 0.2 and 100 mg.L-1. The response sensitivity was approximately 0.1 mg.L-1 and the coefficients of variation in the assay were within 8% for both compounds. A typical application in oxidation phenotyping was presented for one healthy volunteer who received 100 mg of oral metoprolol.
CONCLUSION: The method can be used for the investigation of genetic polymorphism of metoprolol oxidation in the large populations.
Keywords:
METHODS: Urine (200 microliters) was diluted with eluate and injected into the chromatograph. Samples were separated on an ODS column by isocratic binary elution and monitored by fluorescence detection.
RESULTS: No potential interfering peaks were identified. M and HM gave rapid elution and baseline resolution. The linear curves of both analytes ranged between 0.2 and 100 mg.L-1. The response sensitivity was approximately 0.1 mg.L-1 and the coefficients of variation in the assay were within 8% for both compounds. A typical application in oxidation phenotyping was presented for one healthy volunteer who received 100 mg of oral metoprolol.
CONCLUSION: The method can be used for the investigation of genetic polymorphism of metoprolol oxidation in the large populations.