Spectacular Application of Isoindole‐Based Fluorophore for Mirabegron Assay in Tablets and Biological Fluids (Urine/Plasma). Assessment of Method Blueness and Whiteness

The FDA has approved mirabegron (MBG) for alleviating urgency in micturition and incontinence. Its mechanism of action involves the activation of β₃-adrenoreceptors. The present research outlines a novel, highly sensitive, and cost-effective protocol for analyzing MBG. The current research relies on MBG interaction with o-phthalaldehyde alongside 2-mercaptoethanol. The resulting isoindole fluorophore was quantified at λ_ex 337.7 and λ_em 433.7 nm. A comprehensive analysis was conducted to systematically examine and enhance the several experimental factors that impact the creation of the isoindole-based fluorophore outcome. A linear correlation was established by precisely manipulating these variables, demonstrating that the increase in fluorescence strength is directly correlated to the quantity of MBG within the range of 30 to 1000 ng/mL. The analytical method was able to reliably detect MBG concentrations as low as 9 ng/mL and accurately quantify levels down to 27.5 ng/mL. This analytical procedure was effectively employed to determine the concentration of MBG in commercially available tablet formulations, as well as in plasma/urine samples. Furthermore, the strategy was extended to assess the content uniformity of MBG-containing products, providing results with satisfactory accuracy and precision. Importantly, this approach is cost-effective, environmentally friendly, and can be readily implemented for quality control and routine monitoring of MBG in pharmaceutical products. The suggested approach was evaluated utilizing the RGB12 and BAGI tools. The outcomes abundantly show the practicability and integrity of the planned strategy.