Five poly(vinyl chloride) (PVC) matrix membrane electrodes responsive to the -blockers atenolol (AT), bisoprolol fumarate (BI), timolol maleate (TI), and levobunolol HCl (LV) were developed and characterized. A precipitation-based technique with ammonium reineckate anion as an electroactive
material in PVC matrix with AT, BI, TI, and LV cations was used for fabrication of Electrodes 14, respectively. Electrode 5 fabrication was based on precipitation of LV cation with tungstophosphate anion as an electroactive material. Fast and stable Nernstian responses at 1 1021
107 M for different -blockers over the pH range of 28 were found for these electrodes, which were evaluated according to International Union of Pure and Applied Chemistry recommendations. The method was successively applied for the determination of -blockers in their pharmaceutical
formulations. Validation of the method according to quality assurance standards showed the suitability of the proposed electrodes for use in the quality control assessment of these drugs. The recoveries for the determination of the -blocker drugs by the 5 proposed selective electrodes were
100.1 0.7, 99.9 0.8, 100.0 1.1, 100.5 1.1, and 100.6 0.7% for Sensors 15, respectively. Statistical comparison between the results obtained by this method and the official method of the drugs was performed and no significant difference was found.
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