Two-dimensional near-IR correlationspectroscopy study the interaction of protein and famotidine in acidic pH region

The changing of protein in secondary structure and the binding between protein and famotidine in acid aqueous solutions were studied by Fourier-transform near-infrared spectrospy combined two-dimensional correlation analysis, pH-perturbed 2-D correlation spectra are calculated for the spectra in the 4850-4200, 7500-5350 and 6000-5000 cm−1 regions at different pH values. We observed that there is a binding between atom S of sulfanilamide radical and COOH of protein in 5742 cm−1 and we also can explore the change of protein in the secondary structure simultaneously.