Stability Indicating RP-HPLC Method Development and Validation for The Quantitative Estimation of Inosine Pranobex in Bulk and Tablet Dosage Form

Aim: The objective of the present study was to develop a novel RP-HPLC method for Inosine Pranobex using a unique mobile phase ratio for the first time and validate a simple, rapid, precise, and accurate reverse-phase high-performance liquid chromatography (RP-HPLC) method for the estimation of Inosine Pranobex in bulk drug and tablet dosage form, followed by forced degradation studies to assess the stability-indicating nature of the method. Methodology: Chromatographic separation was achieved on a Shimadzu C18 column (4.6 × 250 mm ×5 µm) using a mobile phase consisting of water: acetonitrile: methanol in the ratio of 80:10:10 %v/v/v. The flow rate was maintained at 0.7 ml/min, and detection was carried out at 259 nm using a UV detector. Results: The method exhibited good linearity in the concentration range of 20–100 µg/ml, with correlation coefficient (R² 0.9999) values meeting ICH acceptance criteria. System suitability testing showed peak asymmetry factors of < 1.0 and theoretical plate numbers greater than 2000, indicating efficient chromatographic performance. The % RSD for precision studies was found to be less than 2.0 %, confirming method reproducibility. Forced degradation results demonstrated that there was no significant interference from degradation products at the retention time of the analyte, confirming the stability-indicating property of the method. Conclusion: The developed RP-HPLC method is simple, precise, accurate, and robust, and can be successfully applied for routine quantitative estimation of Inosine Pranobex in bulk and tablet dosage forms, as well as for stability assessment under forced degradation conditions.