Breakthrough RP-HPLC strategy for synchronous analysis of pyridine and its degradation products in powder for injection using quality metrics.

We have developed a novel, sustainable, and quality-by-design (QbD) driven RP-HPLC method to simultaneously identify pyridine in powder for injection and its degradation products. The goal of this method is to meet the growing demand for robust, eco-friendly methods of quality control for pharmaceutical products. QbD ensured method robustness, while minimizing solvent consumption and waste generation to ensure sustainability. Several sustainable tools were investigated to assess their ecological impact in the study. Using Box-Behnken design, three chromatographic parameters were optimized: column oven temperature, flow rate, and buffer pH. An ethanol and buffer solution mobile phase at pH 6.5 in gradient mode was found to be optimal. An Avantor Hichrom C18 (0.46 cm × 15 cm, 5 µm) column was used with UV detection at 254 nm and pumped at 1.0 mL/min. The linearity of pyridine occurred in the 0.13-40 µg/mL range with an R2 of 0.9999. Pyridine was tested for acidity, basicity, oxidation, sunlight, and heat according to rules are set forth by the International Council for Harmonization (ICH). Degradation caused by bases, acids, and oxidation provided the highest degradation rates. Incorporating quality-by-design principles with sustainability considerations makes this method robust, eco-friendly, and cost-effective for quality control in pharmaceutical products. Having been successfully applied to powder of injection, its utility in the pharmaceutical industry is unquestionable.