Stability-Indicating and RP-HPLC Method for Analyzing Amlodipine Besylate in Commercially Available Drug Products in Kurdistan, Iraq

This study aims to develop and validate a stability-indicating HPLC method for the simultaneous determination of Amlodipine (Amlo) in bulk and tablet dosage forms. The method’s goal is to evaluate the stability and degradation of Amlo under various stress conditions. The method was optimized using high-performance liquid chromatography (HPLC) with a UV detector. The mobile phase consisted of water and methanol in a 50:50 (v/v) ratio. An Eclipse XDB-C18 column (4.6 mm × 250 mm, 5 μm) was used for separation. The analysis was carried out at room temperature (25°C) with a 10 μL injection volume, a flow rate of 1.2 mL/min, and detection at 360 nm. Method validation was conducted in terms of linearity, precision, accuracy, limit of detection (LOD), and limit of quantification (LOQ). The stability of Amlodipine in tablet forms, under various stress conditions (acidic, alkaline, oxidative, thermal, and photolytic), was also evaluated. The finding showed excellent linearity (R² = 0.994) in the concentration range of 5–25 μg/mL. Precision was demonstrated by a relative standard deviation (RSD) of less than 0.8%. The LOD and LOQ were found to be 0.65 μg/mL and 2.16 μg/mL, respectively. Accuracy was assessed at three different levels, yielding recoveries above 98%. The method successfully detected the degradation products of Amlo under the applied stress conditions. The developed and validated HPLC method is simple, precise, and accurate for the simultaneous determination of Amlodipine in bulk and tablet forms. It is reliable for evaluating the stability and degradation of Amlo under different stress conditions, making it suitable for routine quality control and stability testing of Amlo-based pharmaceutical products.