A D–π–A-type ratiometric fluorescent probe to detect polarity changes and inhibition effect during ferroptosis

To thoroughly understand ferroptosis's biological functions in living cells, it is crucial to investigate the polarity variations that occur during this unique Fe(II)-facilitated oxidative type of cell death. In this work, we report the development of a ratiometric probe (Po-P) to visualize the polarity changes in living cells and the inhibition effect during ferroptosis. The polarity-responsive fluorophore utilized by Po-P has a D-π-A-type structure. Based on theoretical calculations, ICT was proposed as the basis for Po-P's polarity-responsive mechanism. According to cell imaging results, Po-P had a desirable capacity for monitoring polarity fluctuations and erastin-induced ferroptosis. Furthermore, inhibition imaging revealed that dihydrolipoic acid (DHLA) could potentially prevent polarity changes that occur during erastin-induced ferroptosis, just as vitamin E (VE). We anticipate that the probe Po-P could be a valuable tool to quickly monitor polarity fluctuations and inhibition effects during ferroptosis and create new medications for treating disorders related to ferroptosis.