Robust method operable design region for economical and eco‐friendly chromatographic analysis of azilsartan medoxomil and cilnidipine by incorporating a hybrid approach of green analytical chemistry and analytical quality by design

According to the concept of green analytical chemistry, the analytical method development should be carried out by avoiding or minimizing the usage of toxic organic solvents for the safety of human and aquatic animal life and the protection of the environment. Hence, the green analytical chemistry (GAC)‐assisted robust liquid chromatographic method has been developed for chromatographic analysis of azilsartan medoxomil and cilnidipine (CIL) using safe organic solvents. The chromatographic method was developed by the implementation of analytical quality by design using chemometrics and response surface modeling. The chromatographic separation was carried out using Shim‐Pack C18 (250 × 4.6 mm, 5.0 μm) column as stationary phase and ethanol: 0.1% V/V ammonia solution (45:55, %V/V) as mobile phase. The chromatographic peak of AZL and CIL was found to be at the retention time of 3.5 and 4.5 min, respectively. The flow rate was kept at 1.0 mL/min and the column oven temperature was set to 40˚C. The developed method was found to be validated as per the International Council for Harmonization Q2 (R1) guideline. The method was applied for the assay of fixed‐dose combination and results were found in compliance with the labeled claim. The greenness of the method was evaluated using GAC tools.