Multi-spectroscopic and molecular docking technique study of the azelastine interaction with human serum albumin

Fluorescence and circular dichroism spectroscopic techniques and molecular docking were used to study binding of azelastine with human serum albumin (HSA). Time resolve fluorescence spectroscopy results indicated that the quenching mechanism is dynamic. Fluorescence quenching results demonstrated that the binding of azelastine to HSA is weak, binding reaction is spontaneous. There is fluorescence energy transfer from tryptophan of HSA to bound azelastine. 2.34 nm is the binding distance calculated from FRET data. Molecular docking results suggested that the binding site for azelastine in HSA is located in subdomain II A. Interaction of azelastine to HSA induced ordered secondary structure in HSA. Binding of azelastine to HSA can affect pharmacokinetics of drug. Hence, rationalizing drug dosage is important for clinical application of azelastine. (C) 2019 Elsevier B.V. All rights reserved.