Analytical quality by design and greenness assessment–based RP-HPLC method development for stability-indicating assay of Tafamidis

Abstract

A novel Analytical Quality by Design (AQbD)-based stability indicating assay method using reverse-phase high-performance liquid chromatography (RP-HPLC) integrated with green analytical assessment was developed and validated for the Tafamidisin bulk drug. Critical analytical parameters, including flow rate, mobile phase composition, and pH, were systematically optimized using custom design in Design of Experiments (DoE). The optimized chromatographic conditions provided efficient separation with a retention time of 2.230 min. The method exhibited excellent linearity over the concentration range of 50–150 µg/mL (R² = 1.00), with limits of detection and quantification of 0.47 µg/mL and 1.59 µg/mL, respectively as per ICH Q2 R1 guidelines. The forced degradation study performed in typical stress conditions. Under acid and thermal, degradation were high impact of 10.4% and 8.9%, respectively within acceptable range. Greenness assessment using AGREE and MoGAPI yielded scores of 0.82 and 84, indicating excellent environmental sustainability. The developed AQbD-based RP‑HPLC method offers a rapid and robust analytical platform that is environmentally sustainable, highly reliable, and stability indicating, making it ideally suited for routine quality control of Tafamidis active pharmaceutical ingredient (API) and extending its applicability to finished pharmaceutical formulations in compliance with regulatory standards.