Characterization of interaction between C.I. Acid Green 1 and human serum albumin: Spectroscopic and molecular modeling method

The binding characteristics of human serum albumin with C.I. Acid Green 1 were studied by employing fluorescence, resonance light scattering, ultraviolet–visible, circular dichroism, Fourier transform infrared techniques and molecular modeling. Spectroscopic analysis has revealed that quenching of human serum albumin by C.I. Acid Green operates by a static quenching mechanism. The results by Fourier transform infrared, circular dichroism and ultraviolet–visible absorption spectra experiment indicated that the secondary structures of protein were changed in the presence of C.I. Acid Green 1. Molecular modeling revealed that a dye–protein complex was stabilized by hydrophobic forces, Van-der-Waals force and hydrogen bonding, via amino acid residues. Furthermore, influences of coexisting substances on the binding constant of C.I. Acid Green 1-human serum albumin complexes were investigated.