XPS Analysis of Enzyme and Mediator at the Surface of a Layer-by-Layer Self-Assembled Wired Enzyme Electrode

High potential purified Trametes trogii laccase has been deposited in mono- and multilayer thin films on gold surfaces by layer-by-layer electrostatic adsorption self-assembly. The osmium bipyridil redox relay sites on polycation poly(allylamine) backbone efficiently work as a molecular “wire” in ox...

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Detalles Bibliográficos
Autores: Scodeller, Pablo David, Williams, Federico José, Calvo, Ernesto Julio
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2014
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/31725
Acceso en línea:http://hdl.handle.net/11336/31725
Access Level:acceso abierto
Palabra clave:Xps
Laccase
Layer by Layer
Osmium
https://purl.org/becyt/ford/1.4
https://purl.org/becyt/ford/1
Descripción
Sumario:High potential purified Trametes trogii laccase has been deposited in mono- and multilayer thin films on gold surfaces by layer-by-layer electrostatic adsorption self-assembly. The osmium bipyridil redox relay sites on polycation poly(allylamine) backbone efficiently work as a molecular “wire” in oxygen cathodes for biofuel cells. X-ray photoelectron spectroscopy of Cu 2p3/2 and Os 4f signals provided chemical information on the enzyme and redox mediator surface concentrations after different adsorption steps. The electrical charge involved in oxidation–reduction cycles of the osmium sites, the ellipsometric enzyme film thickness, and the mass uptake from quartz crystal microbalance experiments, correlate with the XPS surface concentration, which provides unique evidence on the chemical identity of the composition in the topmost layers. XPS is shown to be an important analytical tool to investigate stratified copper and osmium distribution in LbL thin films relevant to biosensors and biofuel cells.