Method Development and Validation for the Estimation of Liraglutide and Its Related Substances by using RP-HPLC

A robust and precise gradient reversed-phase high-performance liquid chromatography (RP-HPLC) method was developed and validated for the simultaneous estimation of Liraglutide and its related impurities Des-acetyl Liraglutide (Impurity A) and Glycosylated Liraglutide (Impurity B). The optimized chromatographic conditions employed an Inertsil C18 column (250×4.6 mm, 3μm) with a mobile phase of NAH₂PO₄ buffer (pH 4) and methanol under gradient elution. System suitability parameters, including resolution (>2), tailing factor (2000), confirmed the method’s efficiency and reliability. Linearity was demonstrated across concentration ranges of 40–200 µg/mL for Liraglutide and 4–20µg/mL for impurities, with correlation coefficients (R²>0.999) indicating excellent linearity. The method exhibited high precision (%RSD