Delving into the Inception of BODIPY Dyes: Paradigms of In Vivo Bioimaging, Chemosensing, and...

Boron-dipyrromethene (BODIPY) dyes belong to a class of organoboron compounds that have become ubiquitous for researchers in areas of fluorescence imaging, photodynamic therapy, and optoelectronics. The intrinsic qualities of BODIPY dyes and their meso-modified structural analogs, Aza-BODIPY dyes, have propelled their recent increase in use in biomedical applications. The two scaffolds have high quantum yields, narrow absorption, and emission bandwidths with large Stokes' shifts, and high photostability and thermal stability. Because their properties are independent of solvent polarity and dye functionality, they can be tuned to promote novel analytical methods, resulting in the adaptation of the physicochemical and spectral properties of the dyes. In this review of BODIPY and Aza-BODIPY scaffolds, we will summarize their spectral properties, synthetic methods of preparation, and applications reported between 2014 and 2025. This review aims to summarize the advances in chemosensing, especially pH sensor development, and the advances in NIR-II window bioimaging probes. We hope that this succinct overview of Aza-BODIPY scaffolds will highlight their untapped potential, elucidating insights that may catalyze novel ideas in the physical organic realm of BODIPY.