Characterization of the Interaction between Human Serum Albumin and Minocycline by Spectroscopic Methods

Abstract

In this paper, the interaction between human serum album (HSA) and minocycline (MNC) in physiological solution had been studied by fluorescence spectroscopy, UV spectrum and FT-IR spectroscopy. The inner filter effect was corrected. The results indicated that the fluorescence quenching of HSA was primarily due to static quenching, and thermodynamic parameters exhibited hydrogen bond and van der Waals force played the major role in stabilizing HSA-MNC complex. Through site marker competitive experiments had been assigned to possess the high-affinity binding site for MNC in subdomain IIA of HSA. Binding constant was obtained to be 1.64×106L·mol-1(298K) and 1.16×104L·mol-1(310K), the number of binding sites were both 1. The alternations of HSA secondary structure, such as α-helix and β-sheet were quantitatively calculated from FT-IR.