In spite of their relatively low fluorescence quantum yield, cyanine dyes such as Cy3Cy5, or Cy7 are widely used in fluorescence-based applications due to their high extinction coefficients and excellent photon yields.

The known quantum yields for Cyanine dyes are available in table below:

NameMWQuantum yield
Cy27140.12
Cy37670.15
Cy3.511020.15
Cy57920.27
Cy5.511280.28
Cy78180.28