REVERSED-PHASE HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY (RP- HPLC) BASED ANALYTICAL METHOD DEVELOPMENT AND VALIDATION FOR PHARMACEUTICAL DOSAGE FORMS: A COMPREHENSIVE REVIEW

High-performance liquid chromatography (HPLC) has long served as the central tool for checking the quality of pharmaceutical products. As drug formulations grow more complex— often combining multiple active ingredients or utilizing advanced delivery matrices—the industry requires highly reliable analytical techniques to ensure product safety and clinical efficacy. Reversed-phase HPLC (RP-HPLC) remains the preferred choice in most quality control laboratories because it delivers excellent peak resolution, handles a wide variety of compounds, and yields highly reproducible results. This review provides a detailed look at how RP-HPLC methods are developed and validated for modern dosage forms today. We break down the core physicochemical factors that drive separations, such as stationary phase chemistry, mobile phase selection, and the critical role of pH in controlling analyte ionization. Additionally, the paper discusses the industry's significant shift away from traditional trial-and-error testing toward Analytical Quality by Design (AQbD), a structured approach now heavily emphasized by the ICH Q14 guidelines. We also walk through the strict validation requirements set by ICH Q2(R2), explaining the practical importance of testing for specificity, forced degradation, linearity, accuracy, precision, and overall method robustness. Finally, the review explores recent technological upgrades from the past few years, including the rise of core-shell columns, two-dimensional liquid chromatography (2D-LC), and the push for greener analytical practices. By highlighting these trends alongside the potential future impact of artificial intelligence on method optimization, this paper serves as a practical blueprint for researchers looking to build and validate robust, regulatory-compliant RP-HPLC procedures.