Synthesis of Homologous Fluorescent Carboxylates and their Application to the Study of Bovine Serum Albumin

The synthesis of four fluorescent carboxylate probes with spacer groups comprising 1 to 12 atoms between the dansyl and carboxylate functions is described. These probes bind specifically to bovine serum albumin with changes in fluorescence properties. Dansyl glycine shows significantly different behavior in comparison with its longer homologs. Probe binding to protein is diminished in the presence of fatty acids. Evaluation of binding stoichiometries, dissociation constants, and limiting fluorescence values suggests that dansyl glycine binds at a site distinct from the binding site for the longer homologs