Maintaining the therapeutic integrity of medicinal products is fundamentally dependent on the precision of analytical testing frameworks. Reversed-Phase High-Performance Liquid Chromatography (RP-HPLC) has emerged as the most reliable analytical platform for the quantitative assessment of active pharmaceutical ingredients (APIs), antimicrobial preservatives, and complex degradation profiles. This review presents a critical evaluation of the modern RP-HPLC landscape, focusing on systematic method development and the transition toward structured analytical workflows. We examine the core mechanisms of hydrophobic partitioning, the tactical selection of stationary phases—specifically C8 and C18—and the nuanced optimization of mobile phase variables such as pH, buffer concentration, and organic modifiers. Additionally, the article explores the rigorous validation protocols mandated by the International Council for Harmonisation (ICH) Q2(R1) guidelines, specifically addressing specificity, linearity, precision, and robustness. By synthesizing current research from 2018 to 2025, this work serves as a practical blueprint for quality assurance professionals seeking to establish stability-indicating assays that comply with evolving global regulatory expectations. The integration of high-resolution particle technology and optimized gradient strategies ensures that RP-HPLC remains a high-throughput pillar in pharmaceutical manufacturing and product lifecycle management.
Deepesh Khandelwal1*, Shaziya Yasmeen2, Anju Goyal3 (Sun,) studied this question.