ATTO 465 is a new fluorescent label derived from the well-known dye Acriflavin. Characteristic features of the label are strong absorption, high fluorescence quantum yield, and high thermal and photostability. In aqueous solution the dye shows a surprisingly large Stokes-Shift of 55 nm. At low temperatures or embedded in a polymeric matrix the dye shows intense after-glow (phosphorescence).

ATTO 465 is a cationic dye and is supplied as a crystalline solid in form of a solvent-free perchlorate salt. The dye is moderately hydrophilic. Its NHS-ester and maleimide show excellent solubility in polar solvents like DMF, DMSO or acetonitrile. For details of coupling see our recommended labeling procedure (PDF). The fluorescence can be excited efficiently in the range 420 - 465 nm.