8-Aminopyrene-1,3,6-trisulfonic Acid (sodium salt)

8-Aminopyrene-1,3,6-trisulfonic acid (APTS) is an anionic fluorescent dye with excitation/emission spectra of 425/503 nm, respectively. It forms a ground state complex with viologen-type quenchers, inducing a red-shift in the absorbance spectrum from 425 to 464 nm. APTS is pH insensitive, with the emission maximum remaining constant over the pH range of 4-10. It can be used in solution or immobilized through attachment of an aldehyde functionalized monomer by reductive amination without significantly changing fluorescence intensity. APTS has been used as a reporter for glucose sensing and for the detection of other saccharides.