title: Dependence of the direct electron transfer activity and adsorption kinetics of cytochrome c on interfacial charge properties.
abstract: With the advantages of in situ analysis and high surface sensitivity, surface-enhanced infrared absorption spectroscopy in attenuated total reflection mode (ATR-SEIRAS) combined with electrochemical methods has been employed to examine the interfacial direct electron transfer activity and adsorption kinetics of cytochrome c (cyt c). This work presents data on cyt c adsorption onto negatively charged mercaptohexanoic acid (MHA) and positively charged 6-amino-1-hexanethiol (MHN) self-assembled monolayers (SAMs) on gold nanofilm surfaces. The adsorbed cyt c displays a higher apparent electron transfer rate constant (33.5 ± 2.4 s(-1)) and apparent binding rate constant (73.1 ± 5.2 M(-1) s(-1)) at the MHA SAMs surface than those on the MHN SAMs surface. The results demonstrate that the surface charge density determines the protein adsorption kinetics, while the surface charge character determines the conformation and orientation of proteins assembled which in turn affects the direct electron transfer activity.
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China. xhxia@nju.edu.cn.
authors.forename: Gui-Xia
authors.initials: GX
authors.lastname: Wang
authors.forename: Min
authors.initials: M
authors.lastname: Wang
authors.forename: Zeng-Qiang
authors.initials: ZQ
authors.lastname: Wu
authors.forename: Wen-Jing
authors.initials: WJ
authors.lastname: Bao
authors.forename: Yue
authors.initials: Y
authors.lastname: Zhou
authors.forename: Xing-Hua
authors.initials: XH
authors.lastname: Xia
mesh_terms: D000327:Adsorption / Q000502:physiology*; D000818:Animals; D045304:Cytochromes c / Q000737:chemistry* / Q000378:metabolism*; D004579:Electron Transport / Q000502:physiology*; D006736:Horses; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D013499:Surface Properties
chemical_list: D045304:Cytochromes c