Studies on the interaction of edible dyes with protein I

The binding of bovine serum albumin (BSA)-edible dyes was studied by spectrophotometric method. The edible dyes used in this study were amaranth, erythrosine, tartrazine and sunset yellow. The binding free energies and binding sites were determined at pH 7.4. The ranges of edible dye concentration were from 0.3 to $7{\times}10^{-5}$M, and those of BSA were from 0.15 to $3{\times}10^{-5}$M. The binding free energies of BSA-edible dyes were from -6, 300 to -8, 100 cal/mole.