Method Development, Validation and Estimation of Single Synthetic Drug Tafamidis by RP-HPLC and Green Analysis in API Form and Pharmaceutical Dosage Form

Abstract

For the quantitative determination of Tafamidis in bulk and pharmaceutical dosage forms, a straightforward, accurate, precise, and environmentally friendly reverse-phase high-performance liquid chromatographic (RP-HPLC) method was developed and validated. To achieve optimal chromatographic performance, several stationary-phase and mobile-phase compositions were evaluated during method development. A Develosil ODS C18 column (4.6 × 150 mm, 5 µm) with a mobile phase consisting of ethanol and phosphate buffer (20:80 v/v, pH 2.8), delivered at a flow rate of 0.8 mL/min, with detection at 235 nm, provided the optimum conditions. The method demonstrated a high theoretical plate count, good peak symmetry, and a retention time of approximately 2.26 minutes. The developed method was validated in accordance with ICH criteria. The system suitability parameters were within acceptable limits, with a %RSD of less than 2%. The method showed good linearity across the concentration range of 6–14 µg/mL, with a correlation coefficient (r) of 0.999. Precision studies demonstrated high repeatability, with %RSD values below 1%. The accuracy of the method was confirmed by percentage recoveries ranging from 100.42% to 101.20%. The limit of quantitation (LOQ) and limit of detection (LOD) were 2.9 µg/mL and 0.95 µg/mL, respectively. The assay of the commercial formulation showed 99.40% purity. Robustness studies indicated that small changes in chromatographic conditions had no discernible effect on method performance. In addition to analytical validation, the environmental impact of the method was assessed using Green Analytical Chemistry (GAC) evaluation tools, including AGREE, Analytical Eco-Scale, and GAPI. An AGREE score of 0.78 demonstrated good adherence to green analytical principles. The method achieved an Analytical Eco-Scale score of 91, indicating a good green analytical process. The GAPI assessment showed predominantly green zones with minimal environmental impact, largely owing to the use of ethanol as a green solvent, reduced solvent consumption, and the elimination of derivatisation steps. Overall, the developed RP-HPLC method is robust, reliable, and environmentally friendly, making it suitable for routine quality control analysis of Tafamidis in pharmaceutical formulations while supporting sustainable analytical chemistry principles.