Chemistry Publications
Document Type
Article
Publication Date
2-25-2015
Journal
ACS Appl Mater Interfaces
Volume
7
Issue
7
First Page
4081
Last Page
4088
URL with Digital Object Identifier
https://doi.org/10.1021/am507972b
Abstract
In this proof-of-concept study, the fabrication of novel Au nanostructured indium tin oxide (Au-ITO) surfaces is described for the development of a dual-detection platform with electrochemical and localized surface plasmon resonance (LSPR)-based biosensing capabilities. Nanosphere lithography (NSL) was applied to fabricate Au-ITO surfaces. Oligomers of α-synuclein (αS) were covalently immobilized to determine the electrochemical and LSPR characteristics of the protein. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were performed using the redox probe [Fe(CN)6](3-/4-) to detect the binding of Cu(II) ions and (-)-epigallocatechin-3-gallate (EGCG) to αS on the Au-ITO surface. Electrochemical and LSPR data were complemented by Thioflavin-T (ThT) fluorescence, surface plasmon resonance imaging (SPRi), and transmission electron microscopy (TEM) studies. EGCG was shown to induce the formation of amorphous aggregates that decreased the electrochemical signals. However, the binding of EGCG with αS increased the LSPR absorption band with a bathochromic shift of 10-15 nm. The binding of Cu(II) to αS enhanced the DPV peak current intensity. NSL fabricated Au-ITO surfaces provide a promising dual-detection platform to monitor the interaction of small molecules with proteins using electrochemistry and LSPR.
Notes
“This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Applied Materials and Interfaces, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/doi/pdf/10.1021/am507972b”