It serves as a fluorescent probe for protein conformational studies monitoring foldingunfolding via hydrophobic binding in cyclodextrin inclusion complex research sodium-selective fiber-optic sensors and surfactant molecular assemblies.

Its primary purpose is detecting hydrophobic regions in proteinsfree ANS shows weak fluorescence (ex 388 nm em 545 nm) but binding shifts emission to 470 nm with 40-fold intensity increase at pH 8 ideal for studying conformational changes.

8-Anilino-1-naphthalenesulfonic acid ammonium salt (CHNOS) also known as 18-ANS ammonium salt ANSA or Ammonium 8-anilino-1-naphthalenesulfonate (CAS 28836-03-5) is a fluorescent dye appearing as a solid with molecular weight 316.37 gmol melting point 245253C.