title: Binding of fullerol to human serum albumin: spectroscopic and electrochemical approach.
abstract: The potential impact of human exposure to carbonaceous nanomaterials in the environment becomes a concerning issue. Here we report on the interaction of fullerol with human serum albumin (HSA) using spectroscopic and electrochemical methods. The water-soluble fullerene derivative (fullerol) was synthesized and characterized by IR, (1)H NMR, TG-DSC, XRD, HR-TEM, etc. The spectroscopic methods show that the fluorescence quenching of HSA by fullerol is the result of the formation of an HSA-fullerol complex. Binding parameters such as ΔG, ΔH and ΔS were calculated, and the quenching constant K(a) at different temperatures was determined using the modified Stern-Volmer equation. The electrochemical experiments further confirmed the conclusions. In addition, the influences of coexisting heavy metal ions have also been studied in the present system. The circular dichroism spectra (CD), 3D fluorescence spectra and FT-IR spectra results suggest that the secondary structure of HSA was changed by fullerol. Based on the site marker competitive experiments, we can predict the possible binding position of fullerol on the HSA was located at the site of sub domain II A. Furthermore, the distance r between donor (HSA) and acceptor (fullerol) was obtained according to the famous fluorescence resonance energy transfer (FRET) mechanism.
authors.affiliation: State Key Laboratory of Virology & Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, PR China.
authors.forename: Mei-Fang
authors.initials: MF
authors.lastname: Zhang
authors.forename: Zi-Qiang
authors.initials: ZQ
authors.lastname: Xu
authors.forename: Yu-Shu
authors.initials: YS
authors.lastname: Ge
authors.forename: Feng-Lei
authors.initials: FL
authors.lastname: Jiang
authors.forename: Yi
authors.initials: Y
authors.lastname: Liu
mesh_terms: D001665:Binding Sites; D002942:Circular Dichroism; D058266:Dielectric Spectroscopy; D031541:Fluorescence Resonance Energy Transfer; D037741:Fullerenes / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D011485:Protein Binding; D017433:Protein Structure, Secondary; D012709:Serum Albumin / Q000737:chemistry / Q000378:metabolism*; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D013816:Thermodynamics
chemical_list: D037741:Fullerenes; D012709:Serum Albumin