Integrated approach of white analytical chemistry and design of experiments to microwave-assisted sensitive and eco-friendly spectrofluorimetric estimation of mirabegron using 4-chloro-7-nitrobezofuran as biosensing fluorescent probe.

The USFDA recently approved mirabegron, a novel once-daily β-3 adrenoceptor agonist for oral administration, as a transformative treatment for overactive bladder. Despite the existence of numerous analytical methods for the assay and bioanalysis of mirabegron, it's perplexing that none have explored the domain of microwave-assisted sensitive spectrofluorimetric method for mirabegron estimation, even after extensive literature review. Adding to the enigma is the insistence of current analytical methods on using expensive and harmful organic solvents, posing a threat to marine life and the broader environment. Recently, the white analytical chemistry approach has been introduced to develop analytical methods that are cost-effective, environmentally friendly, and user-friendly. Consequently, a white analytical chemistry-based, sensitive, and eco-friendly spectrofluorimetric estimation of mirabegron has been initiated, using 4-Chloro-7-nitrobenzofurazan as a fluorescent biosensing probe. The development of this robust method involved a series of experiments designed to minimize solvent and time wastage. Through a combination of fractional factorial and Box-Behnken designs, researchers identified the critical variables and optimized the method to perfection. This method was validated according to the stringent ICH Q2 (R2) and USFDA guidelines, ensuring its reliability and accuracy. Once approved, this sensitive spectrofluorimetric method was tested, accurately estimating mirabegron levels in commercial formulations and rat plasma samples. To further enrich the study, a comprehensive evaluation of existing analytical methods was conducted alongside the proposed spectrofluorimetric method, using advanced tools like the AGREE calculator, GAPI software, and RGB model to assess their eco-friendliness and effectiveness in mirabegron estimation.