New FACE for glycans: Fluorescence Assisted Capillary Electrophoresis enabled by the negatively charged auxochromes in 1-aminopyrenes.

A compact and negatively charged acceptor group - N -(cyanamino)sulfonyl - is introduced to dye design and its influence on the absorption and emission spectra of the "push-pull" chromophores is exemplified by 1,3,6- tris -[(cyanamino)sulfonyl]-8-aminopyrene. The new sulfonamides, including O -phosphorylated (3-hydroxyazetidine)- N -sulfonyl, are negatively charged electron-acceptors and auxochromes. 1-Aminopyrenes decorated with new sulfonamides have three or six negative charges (pH ≥ 8), low m/z ratios, high mobilities in electric field and yellow to orange emission. We labeled maltodextrin oligomers via reductive amination, separated the products by electrophoresis, demonstrated their high brightness in a commercial DNA analyzer and distribution of the emission signal among the detection channels.