2713577-11-6

Biological Activity: RhBIV is a thermosensitive rhodamine B (RhB)-derived fluorescent probe that fluorescently labels cellular mitochondria and detects mitochondrial temperature in vitro and in vivo. RhBIV contains a quaternized rhodamine B core, which confers a positive charge for binding to the negatively charged mitochondrial membrane, and an ortho-substituted electron-donating piperidine group; at lower temperatures, RhBIV forms an unstable ion pair form under kinetic control and exhibits strong fluorescence, whereas elevated temperature disrupts or partially interrupts the ion pair form, favoring formation of the conjugated RhBV form and leading to loss of fluorescence. RhBIV exhibits decreased fluorescence responsiveness with increasing temperature over the range of 20-42°C. RhBIV enables biological imaging of cells and mice, mitochondrial thermogenesis imaging, dynamic observation in mitochondrial thermogenesis imaging experiments, and non-invasive imaging of mitochondrial function in living animals (Ex/Em = 520/592 nm)^[1].