Simultaneous Determination of Metoprolol and Propranolol Using Chemometric-assisted Spectrophotometry and High- Performance Liquid Chromatography

Resolution of binary mixtures of metoprolol and propranolol without sample pretreatment has been successfully achieved, using three different methods. The first method was based on application of Vierodt’s method that involves measurements of the absorbances at 222.6 and 213.4 nm for metoprolol and propranolol. Calibration graphs were established in the range of 1-70 μg/mL and 0.5-30 μg/mLfor metoprolol and propranolol, respectively. The second method describes the use of multivariate spectophotometric calibration by using partial least squares (PLS) analysis of UV spectral data. In the third method, high performance liquid chromatography (HPLC) was performed by using reversed phase column and a mobile phase composed of 0.01 mol/LNaH2PO4 (adjusted to pH 3.0 with phosphoric acid) methanol acetonitril (45:45:10, v:v:v). The proposed methods were validated and results obtained by adopting the three methods were statistically analyzed.