Lipid droplets-targeting multifunctional fluorescent probe and its application in ferroptosis and bioimaging

Unraveling the inherent association between diseases and hypochlorous acid (HOCl), within the microenvironments of lipid droplets (LD) remains a formidable task due to the scarcity of research on multiple disease models. Intracellular HOCl and microenvironments (such as viscosity and polarity), are crucial in upholding redox balance, orchestrating diffusion, transportation and signal transduction within living cells. Nevertheless, the simultaneous visualization of HOCl alongside viscosity and polarity within the milieu of ferroptosis, inflammation, and neoplasia remains unachieved due to the absence of appropriate analytical tools. In response to this pressing need, we have developed an innovative, multifunctional near infrared (NIR) fluorescent probe, termed NCN, capable of simultaneously monitoring HOCl, viscosity, and polarity within lipid droplets. NCN is characterized by its heightened sensitivity to increased viscosity and decreased polarity, which allows it to target LDs with high specificity. Furthermore, the combined application of HOCl, viscosity, and polarity as diagnostic markers for cancer has been triumphantly demonstrated, encompassing cellular and tissue strata as well as in vivo tumor-bearing mouse models. Therefore, our probe offers a reliable means for understanding LD microenvironments and proposes a promising approach for the diagnostic evaluation of diseases.