Please use this identifier to cite or link to this item: http://hdl.handle.net/10316/10399
Title: Enhanced Charge Transport and Incorporation of Redox Mediators in Layer-by-Layer Films Containing PAMAM-Encapsulated Gold Nanoparticles
Authors: Crespilho, Frank N. 
Zucolotto, Valtencir 
Brett, Christopher M. A. 
Oliveira, Osvaldo N. 
Nart, Francisco C. 
Issue Date: 7-Sep-2006
Publisher: American Chemical Society
Citation: The Journal of Physical Chemistry B. 110:35 (2006) 17478-17483
Abstract: In this work, we exploit the molecular engineering capability of the layer-by-layer (LbL) method to immobilize layers of gold nanoparticles on indium tin oxide (ITO) substrates, which exhibit enhanced charge transfer and may incorporate mediating redox substances. Polyamidoamine (PAMAM generation 4) dendrimers were used as template/stabilizers for Au nanoparticle growth, with PAMAM-Au nanoparticles serving as cationic polyelectrolytes to produce LbL films with poly(vinylsulfonic acid) (PVS). The cyclic voltammetry (CV) of ITO-PVS/PAMAM-Au electrodes in sulfuric acid presented a redox pair attributed to Au surface oxide formation. The maximum kinetics adsorption is first-order, 95% of the current being achieved after only 5 min of adsorption. Electron hopping can be considered as the charge transport mechanism between the PVS/PAMAM-Au layers within the LbL films. This charge transport was faster than that for nonmodified electrodes, shown by employing hexacyanoferrate(III) as the surface reaction marker. Because the enhanced charge transport may be exploited in biosensors requiring redox mediators, we demonstrate the formation of Prussian blue (PB) around the Au nanoparticles as a proof of principle. PAMAM-Au@PB could be easily prepared by electrodeposition, following the ITO-PVS/ PAMAM-Au LbL film preparation procedure. Furthermore, the coverage of Au nanoparticles by PB may be controlled by monitoring the oxidation current.
URI: http://hdl.handle.net/10316/10399
ISSN: 1520-6106
DOI: 10.1021/jp062098v
Rights: openAccess
Appears in Collections:FCTUC Química - Artigos em Revistas Internacionais

Files in This Item:
File Description SizeFormat
Enhanced Charge Transport and Incorporation of Redox.pdf222.82 kBAdobe PDFView/Open
Show full item record

SCOPUSTM   
Citations

84
checked on Feb 18, 2020

WEB OF SCIENCETM
Citations 1

88
checked on Nov 2, 2020

Page view(s)

231
checked on Nov 26, 2020

Download(s)

156
checked on Nov 26, 2020

Google ScholarTM

Check

Altmetric

Altmetric


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.