A novel lipid droplets-specific fluorescent bio-probe with large Stokes shift for the marking of living cells and zebrafish

In eukaryotes, lipid droplets (LDs) composed of phospholipid monolayers and neutral lipids are crucial spherical subcellular organelles with diameters ranging from 40 nm to 100 μm. LDs play a pivotal role in various physiological activities and are closely associated with many diseases. Therefore, it is essential to develop a fluorescent probe with excellent photostability and large Stokes shift (∼100 nm) for tracking LDs. Herein, a novel lipid droplet-specific fluorescent bioprobe based on coumarin-substituted p-nitrophenyl ethylene was designed and constructed, which exhibited the desirable effects of excellent photostability, favorable resistance to ionic interference, low cytotoxicity and LDs specificity. As a proof of principle, we labeled and imaged LDs of HeLa cells by Cou-LDs successfully. In eukaryotes, lipid droplets (LDs) composed of phospholipid monolayers and neutral lipids are crucial spherical subcellular organelles with diameters ranging from 40 nm to 100 μm. LDs play a pivotal role in various physiological activities and are closely associated with many diseases. Therefore, it is essential to develop a fluorescent probe with excellent photostability and large Stokes shift (∼100 nm) for tracking LDs. Herein, a novel lipid droplet-specific fluorescent bioprobe based on coumarin-substituted p-nitrophenyl ethylene was designed and constructed, which exhibited the desirable effects of excellent photostability, favorable resistance to ionic interference, low cytotoxicity and LDs specificity. As a proof of principle, we labeled and imaged LDs of HeLa cells by Cou-LDs successfully.