DEVELOPMENT AND VALIDATION OF AN ANALYTICAL RP-HPLC METHOD FOR THE DETERMINATION OF RELATED IMPURITIES IN MESALAMINE

Mesalamine is a key therapeutic agent used in the treatment of inflammatory bowel diseases such as ulcerative colitis and Crohn’s disease. Ensuring its purity and controlling related impurities is critical for drug safety and efficacy. This study focuses on the development and validation of a robust reversed-phase high-performance liquid chromatography (RP-HPLC) method for the simultaneous detection and quantification of three structurally related impurities Impurity G, Impurity K, and Impurity L in mesalamine pharmaceutical formulations. The chromatographic separation was achieved using an Agilent C18 column with an isocratic mobile phase composed of methanol and 0.1% acetic acid (52:48, v/v), at a flow rate of 0.85 mL/min, with detection at 229 nm. The method was validated in accordance with ICH Q2(R2) guidelines, covering critical parameters such as specificity, linearity (R² ≥ 0.999), precision (%RSD ≤ 0.65), accuracy (% recovery 94.8%–96%), robustness, limit of detection (0.20 µg/mL), and limit of quantification (0.62 µg/mL). The assay demonstrated high reliability for quality control applications and routine analysis of mesalamine products. Additionally, the method showed effective impurity resolution without the need for stress-degradation studies, making it stability-neutral. Overall, this validated RP-HPLC method serves as a regulatory-compliant and practical analytical tool for the pharmaceutical industry, ensuring the consistent quality and safety of mesalamine-based therapies.