Abstract:

Mitochondria, a cell organelle with a double membrane structure, plays significant roles in cell metabolism, including energy circulation and ions balance. Some small positively charged molecule fluorescent dyes/probes can label mitochondria due to the traction of the mitochondrial inner membrane negative potential, providing an important visual imaging tool for investigation of mitochondrial morphology and function. However, most mitochondrial dyes/probes are unsatisfactory as targeting marker of mitochondria, because the mitochondrial potential is constantly changing, when the potential reduced, the affinity of the dye accordingly decreases. Especially, the mitochondrial membrane potential will be significantly reduced when cell metabolism is blocked in pathological conditions(such as apoptosis), thus cationic dyes will spread away from mitochondria and result in non-specific fluorescence. Recently, the Kim team and our team proposed a new concept of fixed mitochondrial probe, with the active group of fluorescent molecular probe can be fixed in the mitochondria through the covalent bond, and developed a series of fluorescent probes that stably targeted mitochondria for the quantitative detection of microenvironment pH, viscosity, and membrane potential. We believe that the development of immobilized mitochondrial fluorescent molecular probes is an inevitable trend in tracking and detecting mitochondria with highly dynamic characteristics. Therefore, this paper reviews and prospects the fixable fluorescent dyes of mitochondria.

Key words: mitochondria, fluorescence dyes, fluorescence mark, fixable