title: Electrocatalytical oxidation of hydroquinone with ferrocene covalently bound to L-cysteine self-assembled monolayers on a gold electrode.
abstract: The preparation of a gold electrode modified by ferrocenecarboxylic acid (FcA) covalently bound to L-cysteine self-assembled monolayer (FcA-SAM) is described. The modified electrode shows an excellent electrocatalytic activity for the oxidation of hydroquinone (QH2) and accelerates the electron transfer rate. The anodic overpotential is reduced by ca. 290 mV compared to those obtained at bare gold electrodes. The charge transfer coefficient and the apparent surface electron transfer rate constant for the redox couple of Q/QH2 at the modified electrode are found to be 0.425 and 0.96 s(-1), respectively. The catalytic current response of DPV increases linearly with the QH2 concentration from 5.7 x 10(-7) to 3.2 x 10(-4) M. The estimation of QH2 in a simulative sample is satisfactory. The method is simple, quick, and sensitive.
authors.affiliation: School of Chemistry and Materials Science, Anhui Normal University, Wuhu 241000, PR China. xianghuideng@yahoo.com.cn
authors.forename: Xian-wen
authors.initials: XW
authors.lastname: Kan
authors.forename: Xiang-hui
authors.initials: XH
authors.lastname: Deng
authors.forename: Wen-zhi
authors.initials: WZ
authors.lastname: Zhang
authors.forename: Guang-Feng
authors.initials: GF
authors.lastname: Wang
authors.forename: Mao-guo
authors.initials: MG
authors.lastname: Li
authors.forename: Hai-sheng
authors.initials: HS
authors.lastname: Tao
authors.forename: Bin
authors.initials: B
authors.lastname: Fang
mesh_terms: D002384:Catalysis; D003545:Cysteine / Q000737:chemistry*; D004563:Electrochemistry / Q000379:methods*; D004566:Electrodes; D005296:Ferrous Compounds / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D006873:Hydroquinones / Q000737:chemistry*; D000075163:Metallocenes; D010084:Oxidation-Reduction; D012680:Sensitivity and Specificity
chemical_list: D005296:Ferrous Compounds; D006873:Hydroquinones; D000075163:Metallocenes; C032949:ferrocenecarboxylic acid; D006046:Gold; D003545:Cysteine; C004998:ferrocene; C031927:hydroquinone