Simultaneous Estimation of Fimasartan potassium trihydrate and Atorvastatin calcium with Greenness Assessment using HPLC and UV Spectrophotometric Methods

•Fimasartan potassium trihydrate and Atorvastatin calcium combination may show better efficacy with fewer side effects.•Three analytical methods such as HPLC and two UV spectrophotometric techniques develop for simultaneous estimation and validated.•AGREE metrics confirm greenness of developed methods, minimizing environmental impact. Clinical trials have demonstrated that combining fimasartan potassium trihydrate and atorvastatin calcium produces better results for essential hypertension and dyslipidemia with fewer side effects than individual drugs. However, no analytical method is available to accurately determine both drugs' qualitative and quantitative amounts when used together. Therefore, we are interested in developing and validating three analytical methods for simultaneously estimating fimasartan potassium trihydrate and atorvastatin calcium in laboratory-prepared tablets. These methods include a novel, simple, precise, sensitive, robust HPLC technique, and two UV spectrophotometric methods. The HPLC method used a reversed-phase Shimpack ODS C18 column as a stationary phase with an isocratic procedure. A mobile phase consisting of a mixture of acetonitrile and 0.01 M ammonium acetate buffer, (pH adjusted to 3.7 using formic acid) at a ratio of 70:30 v/v, at a constant flow rate of 1 mL/min and chromatograms were recorded at 234 nm for the two analytes. Vierordt's simultaneous equation method used two wavelengths (247 nm and 263 nm) to estimate the drugs' amounts and derive a simultaneous equation for FIMA and ATOR. Meanwhile, the first-order derivative method used zero-crossing points of 224nm and 261nm to estimate the concentrations of ATOR and FIMA. A statistical analysis using an analysis of variance test revealed no significant differences among the three methods regarding accuracy and precision. Moreover, the three developed methods underwent rigorous statistical validation by the ICH Q2R1 guidelines, demonstrating their successful application in the concurrent analysis of the two drugs in bulk and tablets prepared within the laboratory. To assess the ecological impact of the new UV spectrophotometric technique and HPLC method, the greenness profile was evaluated utilizing Analytical eco scale (AES), National environmental method index (NEMI), the Green analytical procedure index (GAPI), and the software-based Analytical greenness metric (AGREE) tools. This evaluation substantiated the method's environmental friendliness regarding solvent us