BODIPY-1

BODIPY-1 is a lysosome-targeted temperature probe. BODIPY-1 relies on temperature-driven changes in microviscosity and hydrophobicity, as well as its own lysosome-targeting morpholine group; at room temperature, its fluorescence is quenched by intramolecular rotation, but upon heating, the oligo (ethylene glycol) groups undergo thermal dehydration, increasing the microviscosity and hydrophobicity around the fluorophore, which disfavors photoinduced electron transfer (PET) and progressively enhances fluorescence, while aggregates formed above its phase transition temperature also produce fluorescence. In neutral aqueous solution, its detection wavelengths are Ex/Em = 490/542 nm at 25°C and Ex/Em = 490/557 nm at 55°C, and the emission maximum at ~557 nm at high temperature shows more than a 3-fold enhancement^[1].