A dual‐responsive fluorescent probe for imaging viscosity and polarity in nonalcoholic fatty liver disease

Abstract Viscosity and polarity are critical physiological parameters implicated in the onset and progression of nonalcoholic fatty liver disease (NAFLD). Real‐time monitoring of their dynamic variations is of significant importance for the early diagnosis of NAFLD. In this study, BODIPY was utilized as the fluorophore core to successfully develop a dual‐responsive fluorescent probe, Mp BDP‐CF 3 , through the incorporation of a trifluoromethyl (CF 3 ) group at the meso position and methoxyphenyl groups at the 3,5‐positions. The probe demonstrated a high fluorescence quantum yield (approximately 47.86% in 1,4‐dioxane) and excellent photostability. It exhibited remarkable fluorescence sensitivity to variations in both viscosity and polarity within solution and cellular environments, achieving a detection limit as low as 0.41 cP for viscosity. Furthermore, Mp BDP‐CF 3 demonstrated effective targeting of lipid droplets during NAFLD progression. Subsequent in vivo investigations revealed that Mp BDP‐CF 3 facilitated high‐contrast fluorescence imaging and precise discrimination of NAFLD in BALB/c nude mouse models, underscoring its substantial potential for early NAFLD diagnosis.