Electrochemical Studies Based on Local Interfacial pH Changes of Gold Nanoparticles Immobilized on Polystyrene Brushes

Author(s)

Antonio, Tamara R. T. A. ^[1] ; Basso, Caroline R. ^[1] ; Cabral, Murilo F. ^[2] ; Pedrosa, Valber A. ^[1]

Affiliation

^[1] UNESP, Dept Chem & Biochem, Inst Biosci, Botucatu, SP - Brazil

^[2] Univ Estadual Campinas, Dept Genet Evolut & Bioagents, Inst Biol, Campinas, SP - Brazil

• Document type: Journal article
• Source: International Journal of Electrochemical Science; v. 8, n. 3, p. 4150-4159, MAR 2013.
• Web of Science Citations: 8

Abstract

The electrochemical behavior of polystyrene modified with gold nanoparticle (Au NPs) was investigated in terms of pH-responsive polymer brush. A pH-responsive of modified polymer brush from tethered polystyrene was prepared and used for selective gating transport of anions and cations across the thin-film. An ITO-coated glass electrode was used as substrate and applied to study the switchable permeability of the polymer brush triggered by changes in pH of the aqueous environment. The pH-sensitive behavior of the polymer brush interface has been demonstrated by means of cyclic voltammetry (CV) and Localized Surface Plasmon Resonance (LSPR). CV experiments showed at ph values of 4 and 8 induces swelling and shrinking of the grafted polymer brushes, respectively, and this behavior is fast and reversible. LSPR measurements showed a blue shift of 33 nm in the surface resonance band changes by local pH. The paper brings an easy methodology to fabrication a variety of nanosensors based on the polymer brushes-nanoparticle assemblies. (AU)

• FAPESP's process: 10/07478-5 - Chain reaction amplified biocatalytic responses in nanostructured plasmonic sensors
• Grantee: Valber de Albuquerque Pedrosa
• Support Opportunities: Research Grants - Young Investigators Grants