Atto fluorescent labels are designed for high sensitivity applications, including single-molecule detection. Atto labels have rigid structures that do not show any cis-trans isomerization. Thus these labels display exceptional intensity with minimal spectral shift on conjugation.
Atto 590 shows a molar extinction of 120,000 and QY of 80% in water (90% in ethanol). Decay time is 3.7 ns.
Employed in fluorescence energy transfer, FRET, microscopy.