Analytical Method Development and Validation for Estimation of Nadolol and Bendroflumethiazide in Bulk and Tablet Dosage Form by RP-HPLC

Abstract

A simple, rapid, precise, and accurate reverse phase high-performance liquid chromatographic (RP-HPLC) method was developed and validated for the simultaneous estimation of Nadolol and Bendroflumethiazide in bulk drug substances and tablet dosage forms. Chromatographic separation was achieved using a C18 column with an optimized mobile phase consisting of an appropriate mixture of organic solvent and aqueous buffer at a constant flow rate. Detection was carried out at a selected wavelength where both drugs exhibited adequate absorbance.

The proposed method showed good resolution with well-defined and symmetrical peaks for both Nadolol and Bendroflumethiazide. Method validation was performed in accordance with ICH guidelines, evaluating parameters such as specificity, linearity, accuracy, precision, limit of detection (LOD), limit of quantification (LOQ), robustness, and system suitability. The method demonstrated excellent linearity over the selected concentration ranges with correlation coefficients close to unity. Accuracy studies showed satisfactory percentage recovery of both drugs, while precision studies revealed low %RSD values, confirming the reproducibility of the method. Robustness studies indicated that minor deliberate variations in chromatographic conditions did not significantly affect the analytical results.

The validated RP-HPLC method was successfully applied to the quantitative analysis of Nadolol and Bendroflumethiazide in tablet dosage forms, with assay results within acceptable limits. The developed method is suitable for routine quality control analysis of Nadolol and Bendroflumethiazide in bulk and pharmaceutical formulations.