¹Department of Analytical Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz, Iran
²Department of Biochemistry, Faculty of Sciences, Payame Noor University, Tehran, Iran
³Nutrition and Food sciences Faculty, Tabriz University of Medical Sciences, Tabriz, Iran
⁴Nanotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, and Mashhad, Iran DOI : 10.29228/jrp.703 The molecular mechanism of interaction between Mefenamic acid (MA) and human serum albumin (HSA) was investigated. UV-Visible absorption, fluorescence, and FT-IR spectroscopies, with molecular docking, have been used for assay of complex formation, quenching mechanism study, thermodynamic evaluations, and molecular details of the interaction mechanism. The quenching constant (Ksv) of 1.51×105 M-1 was obtained, while the results are indicating the dynamic quenching mechanism. The number of binding sites (n) and apparent binding constants (KA) were 1.51 and 6.55×107 M-1, respectively that resembles positive cooperativity and and strong binding of MA to HSA. The negative sign of standard enthalpy change (ΔH = -88.51 KJ/mol), standard entropy change (ΔS = -146.24 J/mol K), and Gibbs free energy (ΔG = -44.93 KJ/mol) indicated that the van der Waals interactions and hydrogen bonds are facilitating the MA-HSA complex formation. Addition of the metal ions, glucose, urea, and basic pHs decrease the MA-HSA binding constant. Molecular docking simulation showed that mainly positively charged amino acid residues contribute to the MA-HSA interaction. Keywords : Mefenamic acid, NSAID-HSA interaction, Spectroscopy methods, Molecular docking