Simultaneous separation of eight β-adrenergic drugs using titanium dioxide nanoparticles as additive in capillary electrophoresis

The analysis is described for separating seven beta-adrenergic blocking agents (atenolol, celiprolol, clorprenaline, fenoterol, metoprolol, propranolol, terbutaline) and clenbuterol (sympathomimetic beta-2 receptor stimulating agonist, decongestant and bronchodilator, illicit anabolic used in athletics) by CE with UV detection. In order to simultaneously separate all analytes, Tris-H3PO4 solution was applied containing titanium dioxide nanoparticles (TiO2 NPs) as BGEs. The effects of important factors, such as concentration of TiO2. NPs, optimum pH, run buffer concentration, and separation voltage, were investigated so as to achieve best CE separation. The eight analytes could be well separated applying a separation voltage of 15 kV in 75 mM Tris-H3PO4 buffer at a pH of 2.40, containing 6.0 x 10(-6) g/mL TiO2 NPs. Under these optimal conditions, the RSDs for peak areas and for migration times were less than 2.7 and 2.3%, respectively. The detection limits were 0.1 mu g/mL for celiprolol, 0.1 mu g/mL for propranolol, 0.2 mu g/mL for fenoterol, 1.0 mu g/mL for atenolol, 1.0 mu g/mL, for clenbuterol, 1.0 mu g/mL for clorprenaline, 1.0 mu g/mL for metoprolol, and 1.0 mu g/mL for terbutaline. The proposed method was successfully applied for the rapid CE determination of the frequently applied antihypertensive P-blocking compounds atenolol, metoprolol, terbutaline, and propranolol in pharmaceutical tablets.