Characterization of Mercaptoethylamine-Modified Gold Electrode Surface and Analyses of Direct Electron Transfer to Putidaredoxin
| Autor: | Vytas Reipa, Ling Sang Wong, Vincent L. Vilker, William T. Yap |
|---|---|
| Rok vydání: | 1995 |
| Předmět: |
education.field_of_study
Chemistry Diffusion Population Analytical chemistry Chemical modification Surfaces and Interfaces Condensed Matter Physics Electrochemistry Crystallography symbols.namesake Electron transfer Electrode symbols General Materials Science Cyclic voltammetry education Raman spectroscopy Spectroscopy |
| Zdroj: | Langmuir. 11:4818-4822 |
| ISSN: | 1520-5827 0743-7463 |
| DOI: | 10.1021/la00012a038 |
| Popis: | Direct electron transfer to putidaredoxin (Pdx) in solution from bare gold and mercaptoethylamine-modified gold electrodes was studied by cyclic voltammetry. The current response of Pdx at a bare gold electrode was irreversible and highly unstable. The modified electrode offered improved, but still impersistent, quasi-reversible current response. Surface-enhanced Raman spectroscopy revealed that mercaptoethylamine adsorbed on gold was in mixed trans and gauche conformations at 0.0 V (Ag/Agcl) initially. As the potential was changed anodically or cathodically over the range of +0.4 to -0.8 V, the adsorbate population became largely gauche in conformation. A link between the conformation change and deterioration of Pdx current response at the electrode was suggested. Simulations of the electrochemical system yielded an estimated Pdx diffusion coefficient D = 1.4 x 10 -7 cm 2 /s and the apparent heterogeneous electron transfer rate constant k° = 1.0 x 10 -4 cm/s. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|