UV-Spectrophotometric and RP-HPLC Method Development and Validation for Simultaneous Estimation of Gallic Acid,...

Phytochemicals have become the central focus of scientific research in recent times due to their vast applicability and comparatively low side effects. Gallic acid (GA), quercetin (QUE), luteolin (LUT), and apigenin (API) are natural antioxidants that are ubiquitous and co-exist in numerous medicinal plants and have been reported to have therapeutic potential in various diseases. The present study aims to develop and validate a simple, robust analytical method for the simultaneous estimation of these phytoconstituents in various plant extracts and pharmaceutical formulations. The UV and RP-HPLC methods were developed and validated in accordance with ICH Q2 guidelines. The UV method demonstrated good linearity and was found to be robust for the analysis of individual drugs, whereas the gradient HPLC method was suitable for the simultaneous estimation of these drugs. All method validation parameters were within acceptable limits; however, the HPLC method showed slight sensitivity to changes in method parameters, such as flow rate and wavelength. The developed UV spectrophotometric and gradient RP-HPLC methods for the simultaneous estimation of GA, QUE, LUT, and API were validated in accordance with the ICH guidelines. These analytical methods can facilitate simultaneous identification and quantification of phytoconstituents in crude extracts, pharmaceutical formulations, and biological samples.