Determination of Metopolol in Human Plasma Using UHPLC Coupled to Mass Spectrometry

OBJECTIVE To establish a method for determine metopolol in human plasma using UHPLC coupled to mass spectrometry. METHODS The chromatographic separation was achieved on Agilent RRHD PLUS C₁₈column (2.1 mm×50 mm, 1.8 μm), using mobile phase as a mixture of water (0.2% formicacid)-acetonitrile (68:32). The multiple reaction monitoring mode of the positive ion was adopted during MS detection (electrospray ion source), and precursors to the product ion transitions of m/z 268/116, 237/194 were used to measure metoprolol and the internal standard (carbamazepine). RESULTS The calibration curve was linear in the range of 1.012-759.0 ng·mL^-1for metopolol in human plasma (r=0.999 2) with matrix effect of 105.9%, 106.1%, 106.9% and extraction recovery experiments of metoprolol of 83.0%, 99.3%, 95.2%, respectively. The within-run accuracy RSD was ≤ 3.22%, and between-run accuracy RSD was ≤ 4.14%. CONCLUSION The method is simple, accurate, quick and sensitive for determination of metopolol in human plasma.