FerroOrange

Key information: FerroOrange (RhoNox-4) is a highly sensitive and robust fluorogenic probe for the detection of intracellular labile Fe(II). FerroOrange displays weak absorption and low fluorescence in the visible region, but becomes strongly fluorescent upon reaction with Fe(II).

Used for: detection of intracellular labile Fe(II).

Application: high-throughput assays for high content imaging of subcellular labile Fe(II) in live cells; fluorescent microscopy; studies on iron homeostasis and ferroptosis.

Properties and Photophysical Data: FerroOrange has excellent cell-membrane permeability and low cell toxicity. FerroOrange has no chelating ability. For the fluorescent form, excitation and emission maxima (λ) measured in 50 mM HEPES buffer (pH 7.4, 0.2% DMSO) are 545 nm and 575 nm, respectively; extinction coefficient ε = 73,500 M^-1cm^-1; quantum yield φ = 0.19.