Sustainable Ethanol‐Based Reversed‐Phase Liquid Chromatography for Determination of Diltiazem pKa and Quantification with Integrated Green and White Analytical Metrics

value of diltiazem, which has low solubility in water, was calculated. Beyond analytical performance, the sustainability of method was evaluated multimetrically approach using the Environmental, Performance, and Practicality Index, the Carbon Footprint Reduction Index, and the Sustainability of Analytical Methods Index. This complementary framework provides a holistic assessment of operational greenness, carbon intensity, and global sustainability goals in accordance with the latest guidelines. The method for diltiazem determination according to these tools showed linearity with a correlation coefficient of 0.999 in the concentration range of 1.0-15 µg/mL and achieved acceptable precision and accuracy. Validated according to ICH Q2(R2) guidelines, the procedure was successfully applied to tablet formulations and forced degradation studies. This work establishes a comprehensive, ecofriendly methodological approach suitable for pharmaceutical analysis.