Fig 5. The brightness and measured intensity of the dyes in the specific conditions used.

a) Brightness is the product of the quantum yield and the molar absorptivity of the dye. The brightnesses of Eu(III) and Tb(III) are calculated from the quantum yield of their DOTA-complexes and the absorptivities of their acetate salts (our own measurements). b) The measured intensities correspond to the fluorescent signals arising from each fluorescent probe (fully integrated spectra) upon different excitation wavelengths.