Analysis of the binding mechanism for a water-soluble Pd(II) complex containing β-amino alcohols with HSA applying experimental and computational methods

• Published in: Journal of biomolecular structure & dynamics 2024-05, Vol.42 (7), p.3790-3801
• Main Authors: Shahabadi, Nahid, Ghaffari, Lida, Mardani, Zahra, Hadidi, Saba
• Format: Article
• Language: English
• Subjects: fluorescence quenching; human serum albumin; Multi-spectrophotometric and computational methods; Pd(II) complex; site II/subdomain IIIA
• ISSN: 0739-1102; 1538-0254
• DOI: 10.1080/07391102.2023.2216281

In the study ahead, the binding interactions of the [Pd (HEAC) Cl 2 ] complex with human serum albumin (HSA) protein have been assayed in vitro (pH= 7.40) utilizing computational and experimental procedures. The mentioned complex was synthesized as a water-soluble complex from {2-((2-((2-hydroxyethyl)amino)ethyl)amino) cyclohexanol} ligand = HEAC. The results of electronic absorption and circular dichroism investigations illustrated that the hydrophobicity of the Tryptophan microenvironment in HSA undergoes the changes by binding to the Pd(II) complex without substantial perturbations on the protein secondary structure. The fluorescence emission spectroscopy analysis revealed that with rising temperature, the quenching constant (K sv ) in the Stern-Volmer's relation decreases; so, it can be said that the interaction process is along with a static quenching mechanism. The values of 2.88 × 10 5 M −1 , and 1.26 represent the binding constant (K b ) and the number of the binding sites (n), respectively. The Job graph showed the maximum point at χ = 0.5, which means organizing a new set with 1:1 stoichiometry. Thermodynamic profile (ΔH