A novel NIR fluorescent probe for enhanced β-galactosidase detection and tumor imaging in ovarian cancer models.

[Display omitted] • Developed a novel near-infrared fluorescent probe, NRO-βgal, for detecting endogenous β-galactosidase. • The probe demonstrated high selectivity and sensitivity towards β-galactosidase with a low detection limit (LOD = 0.2 U/L) and rapid response time (within 10 min). • NRO-βgal enables effective imaging of β-galactosidase levels in ovarian cancer mouse models, contributing to advancements in tumor detection and surgical interventions. The advancement of biological imaging techniques critically depends on the development of novel near-infrared (NIR) fluorescent probes. In this study, we introduce a designed NIR fluorescent probe, NRO-βgal, which exhibits a unique off–on response mechanism to β-galactosidase (β-gal). Emitting a fluorescence peak at a wavelength of 670 nm, NRO-βgal showcases a significant Stokes shift of 85 nm, which is indicative of its efficient energy transfer and minimized background interference. The probe achieves a remarkably low in vitro detection limit of 0.2 U/L and demonstrates a rapid response within 10 min, thereby underscoring its exceptional sensitivity, selectivity, and operational swiftness. Such superior analytical performance broadens the horizon for its application in intricate biological imaging studies. To validate the practical utility of NRO-βgal in bio-imaging, we employed ovarian cancer cell and mouse models, where the probe's efficacy in accurately delineating tumor cells was examined. The results affirm NRO-βgal's capability to provide sharp, high-contrast images of tumor regions, thereby significantly enhancing the precision of surgical tumor resection. Furthermore, the probe's potential for real-time monitoring of enzymatic activity in living tissues underscores its utility as a powerful tool for diagnostics in oncology and beyond. [ABSTRACT FROM AUTHOR]