Journal of the American Chemical Society · 2012 · 132 citations · 24 references
Natural SciencesBiophysicsCell BiologyBiophotonicsBiophysical ChemistryMolecular ImagingCellular ImagingCellular Responses To HypoxiaFluorescence ImagingFluorescence SpectroscopyPhotophysics Of Fluorescent ProbesReactive Oxygen SpeciesCellular Fluorescence ImagingFörster Resonance Energy Transfer (Fret)Förster Resonance Energy Transfer ImagingFörster Resonance Energy Transfer SensorsHypoxiaLive-cell Fluorescence ImagingLive-cell Imaging ProbesRedox-sensitive Probes
We report a fully reversible off-on fluorescence probe for hypoxia. The design employs QSY-21 as a Förster resonance energy transfer (FRET) acceptor and cyanine dye Cy5 as a FRET donor, based on our finding that QSY-21 undergoes one-electron bioreduction to the radical under hypoxia, with an absorbance decrease at 660 nm. At that point, FRET can no longer occur, and the dye becomes strongly fluorescent. Upon recovery of normoxia, the radical is immediately reoxidized to QSY-21, with loss of fluorescence due to restoration of FRET. We show that this probe, RHyCy5, can monitor repeated hypoxia-normoxia cycles in live cells.
24