Artículos de revistas
Probing the functionalization of gold surfaces and protein adsorption by PM-IRRAS
Fecha
2011Registro en:
CHEMPHYSCHEM, v.12, n.9, p.1736-1740, 2011
1439-4235
10.1002/cphc.201100080
Autor
OLIVEIRA, Rodrigo Marques de
FERREIRA, Jacqueline
SANTOS, Marcos J. L.
FARIA, Roberto Mendonça
OLIVEIRA JUNIOR, Osvaldo Novais de
Institución
Resumen
The control of morphology and coating of metal surfaces is essential for a number of organic electronic devices including photovoltaic cells and sensors. In this study, we monitor the functionalization of gold surfaces with 11-mercaptoundecanoic acid (MUA, HS(CH(2))(10)CO(2)H) and cysteamine, aiming at passivating the surfaces for application in surface plasmon resonance (SPR) biosensors. Using polarization-modulated infrared reflection-absorption spectroscopy (PM-IRRAS), cyclic voltammetry, atomic force microscopy and quartz crystal microbalance, we observed a time-dependent organization process of the adsorbed MUA monolayer with alkyl chains perpendicular to the gold surface. Such optimized condition for surface passivation was obtained with a systematic search for experimental parameters leading to the lowest electrochemical signal of the functionalized gold electrode. The ability to build supramolecular architectures was also confirmed by detecting with PM-IRRAS the adsorption of streptavidin on the MUA-functionalized gold. As the approaches used for surface functionalization and its verification with PM-IRRAS are generic, one may now envisage monitoring the fabrication of tailored electrodes for a variety of applications.