Universal Dark Quencher Based on Clicked Spectrally Distinct Azo Dyes

The first synthesis of an heterotrifunctional molecular scaffold derived from the popular DABCYL azo dye quencher has been achieved. The sequential derviatization of this trivalent azobenzene derivative with two other nonfluorescent azo dyes (Black Hole Quencher BHQ-1 and BHQ-3) and through effective reactions from the bioconjugation chemistry repertoire has led to an universal dark quencher (UDQ). This clicked poly azo dye is able to turn off an array of fluorophores covering the UV/NIR (300-750 nm) spectral range.