Design and synthesis of fluorescent probe for determination of β-glucosidase activity and inhibitor screening

β-Glucosidase (β-Glc) is widely expressed across various organisms and plays essential roles in physiological processes. Notably, β-Glc serves as a diagnostic marker for certain diseases and represents a potential therapeutic target. Developing tools for detecting β-Glc activity and discovering novel β-Glc inhibitors holds significant potential. In this study, we designed and synthesized a novel fluorescent probe named P1, utilizing resorufin as the fluorophore. This probe demonstrates exceptional selectivity, sensitivity (LOD = 8.2 × 10^-5 U/mL), and affinity (K_m = 7.59 μmol/L) towards β-Glc. It enables efficient imageing of β-Glc in living cells and has been successfully applied for screening inhibitors. Using this probe, a novel tricyclic benzimidazole azasugar inhibitor for β-Glc was identified. Overrall, the developed probe represents a powerful tool for β-Glc activity detection and inhibitor screening.