DIMER FORMATION FROM 1-ANILINO-8-NAPHTHALENESULFONATE CATALYZED BY BOVINE SERUM ALBUMIN . A NEW FLUORESCENT MOLECULE WITH EXCEPTIONAL BINDIND PROPERTIES

At pH values around 2, nitrite induces a series of chemical changes in 1-anilino-8-naphthalenesulfonate. From the resulting mixture of products a compound has been isolated, the spectroscopic properties of which are very similar to the parent compound, but with an affinity for bovine serum albumin nearly two orders of magnitude greater than that of the latter. The number of strong binding sites displaying fluorescence enhancement is two. If albumin is present during the formation of the compound, the yield, which otherwise amounts to only 1-2%, approaches 100%, i.e., the protein appears to behave in an enzyme-like fashion. Three different preparative procedures are described. Experimental evidence is given to support the conclusion that the new molecule is a dimer of 1-anilino-8-naphthalenesulfonate. © 1969, American Chemical Society. All rights reserved.