ATTO 390 is a new fluorescent label with a coumarin structure. Characteristic features of the label are high fluorescence quantum yield, large Stokes-Shift and high stability at physiological pH-values. 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).

ATTO 390 is supplied as a crystalline, solvent-free solid. Its fluorescence can be excited efficiently in the range 360 - 410 nm. A useful excitation source is, e.g., a Mercury Arc Lamp with its lines at 365 nm and 405 nm.