UHPLC method for the simultaneous determination of β-blockers, isoflavones and their metabolites in human urine

A rapid-resolution ultra high-performance liquid chromatography separation method (UHPLC) for the simultaneous determination of the following β-blockers: milrinone, sotalol, metoprolol, propranolol and carvedilol, and their metabolites: 5′-hydroxylphenyl-carvedilol, O-desmethylcarvedilol, 4-hydroxypropranolol, α-hydroxy-metoprolol, O-desmethyl-metoprolol; the following isoflavones: genistein, daidzein, glycitin, glycitein, puerarin and biochanin A; as well as their metabolites: dihydrogenistein, desmethylglycitein, 8-hydroxygenistein, daidzein-7,4′-diglucoside, 8-hydroxydaidzein, dihydrobiochanin A in human urine was optimized. The analysed compounds were extracted from human urine by means of solid phase extraction (SPE). The effective UHPLC separation of the examined compounds was applied on a Hypersil GOLD™ (50 mm × 2.1 mm, 1.9 μm) column with a gradient mobile phase system and a UV detector. The complete separation of all analytes was achieved within 8.0 min. The method was validated for the determination of the aforementioned substances in human urine. The linear ranges, limits of detection (LOD) and limits of quantification (LOQ) for β-blockers, isoflavones and their metabolites were determined. The intra- and inter-day precision (%C.V.) was less than 4.48%, and the intra-day and inter-day accuracy was less than 4.74%. The tested SPE sorbent proved that appropriate absolute recoveries can be obtained for Oasis HLB (Waters). The mean recovery of the analytes, using the new SPE procedure, amounted from 70.14% to 99.85%. The present paper reports, for the first time, the method for the determination of β-blockers, isoflavones and their metabolites in human urine samples. The newly developed method was suitably validated and successfully applied for the analysis of the certain of the aforementioned analytes in human urine samples obtained from the patients suffering cardiovascular disease.