Cholesterol Biomimetic Fluorescent Probe for the High Signal‐to‐Noise Ratio and Selectivity Imaging of Nonalcoholic Fatty Liver

ABSTRACT

Nonalcoholic fatty liver disease (NAFLD) lacks sensitive and non‐invasive imaging tools. Conventional fluorescent probes label lipid droplets through non‐specific hydrophobic interactions, failing to distinguish pathological lipid overload from normal lipid storage. Here, we propose an “uptake‐targeted” strategy based on cholesterol biomimicry. TPAS‐PyCHO+ was synthesized as a fluorescent probe that structurally mimics cholesterol to hijack the clathrin‐mediated endocytosis pathway—a process hyperactive in steatotic hepatocytes. In lipid‐laden cells, the probes were actively internalized and accumulated in lipid droplets. TPAS‐PyCHO+ activated aggregation‐induced emission (AIE) to produce strong fluorescence. In contrast, normal hepatocytes show minimal uptake. TPAS‐PyCHO+ achieves high‐contrast imaging of NAFLD in cell and mouse models, with a signal‐to‐noise ratio superior to conventional lipid‐droplet dyes. Moreover, TPAS‐PyCHO+ successfully monitored disease recovery by dietary intervention. This work introduces a biomimetic “uptake‐targeted” design paradigm for metabolic disease imaging by active hijacking of the pathological endocytic pathway.