Electrochemical and STM studies of 1-thio-ß-D-glucose self-assembled on a Au(111) electrode surface.
Langmuir
; 27(21): 13383-9, 2011 Nov 01.
Article
em En
| MEDLINE
| ID: mdl-21939277
ABSTRACT
In this study, a Au(111) electrode is functionalized with a monolayer of 1-thio-ß-D-glucose (ß-Tg), producing a hydrophilic surface. A monolayer of ß-Tg was formed on a Au(111) surface by either (1) potential-assisted deposition with the thiol in a supporting electrolyte or (2) passive incubation of a gold substrate in a thiol-containing solution. For each method, the properties of the ß-Tg monolayer were investigated using cyclic voltammetry (CV), differential capacitance (DC), and chronocoulometry. In addition, electrochemical scanning tunneling microscopy (EC-STM) was used to obtain images of the self-assembled monolayer with molecular resolution. Potential-assisted assembly of ß-Tg onto a Au(111) electrode surface was found to be complicated by oxidation of ß-Tg molecules. The EC-STM images revealed formation of a passive layer containing honeycomb-like domains characteristic of a formation of S(8) rings, indicating the S-C bond may have been cleaved. In contrast, passive self-assembly of thioglucose from a methanol solution was found to produce a stable, disordered monolayer of ß-Tg. Since the passive assembly method was not complicated by the presence of a faradaic process, it is the method of choice for modifying the gold surface with a hydrophilic monolayer.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Microscopia de Tunelamento
/
Eletroquímica
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Glucose
/
Ouro
Tipo de estudo:
Prognostic_studies
Idioma:
En
Ano de publicação:
2011
Tipo de documento:
Article