APTS is a very useful green fluorescent dye for labeling glycoproteins or sugar molecules in general. The labeling occurs via reductive amination which involves the formation of a Schiff base between the amine of APTS and the aldehyde or ketone of the sugar, followed by the reduction of the Schiff base linkage to a stable carbon-nitrogen bond. The multi-anionic nature of the dye makes it ideal for the studies of carbohydrate molecules by high resolution capillary electrophoresis. &lamba; Ex/&lamba; Em: 424/505 nm (before conjugation) Yellow solid soluble in water Store at 4°C and protect from light. C16H8Na3O9S3 MW: 523.39 [196504-57-1]