Insights into the binding interaction of Reactive Yellow 145 with human serum albumin from a biophysics point of view

Abstract

The interaction between Reactive Yellow 145 (RY145) and human serum albumin (HSA) under physiological conditions was studied by the methods of multiple spectroscopic, molecular docking, and molecular dynamic (MD) simulation. Fluorescence data revealed that the fluorescence quenching of HSA by RY145 resulted from the formation of the RY145–HSA complex. According to the modified Stern–Volmer equation, the effective quenching constants (KA) between RY145 and HSA at two different temperatures were obtained to be 114.15 × 104, and 52.55 × 104 L/mol, respectively. ΔH and ΔS were determined to be negative, showing that van der Waals force and hydrogen bonds were the governing intermolecular force in stabilizing the complex. The outcomes of UV– visible spectra, fluorescence spectroscopy, and CD spectra exhibited apparent modifications in the microenvironment and conformation of HSA, particularly for the secondary structure. The MD simulation and molecular docking supported experimental findings.