A unique amphipathic polyethylene glycol-based fluorescent probe for the visualization of lipid droplets and discrimination of living and dead cells in biological systems

Lipid droplets (LDs) play key roles in various physiological processes and the abnormalities of them are related to many diseases. Discrimination of living and dead cells is an important task in the field of pharmacology, pathology and biology. However, the physiological roles of LDs in cell apoptosis has not revealed due to the lack of tools that can visualize LDs as well as discriminate living and dead cells simultaneously. To address this great challenge, a unique amphipathic polyethylene glycol-based fluorescent probe PEG-NBD was rationally designed and synthesized for the visualization of LDs and discrimination of living and dead cells simultaneously. LDs in the living cells under different physiological conditions as well as the tissues were tracked with the new probe. Moreover, the living and dead cells were readily distinguished by dual-channel imaging in cells and zebrafish. This work provides an efficient way for studying LDs related bioprocess and metabolism diseases.