Abstract
The coating of electrical interfaces with reduced graphene oxide (rGO) films and their subsequent chemical modification are essential steps in the fabrication of graphene-based sensing platforms. In this work, electrophoretic deposition (EPD) of graphene oxide at 2.5 V for 300 s followed by vapor treatment were employed to coat gold electrodes uniformly with rGO. These interfaces showed excellent electron transfer characteristics for redox mediators such as ferrocene methanol and potassium ferrocyanide. Functional groups were integrated onto the Au/rGO electrodes by the electro-reduction of an aryldiazonium salt, 4-((triisopropylsilyl)ethylenyl)benzenediazonium tetrafluoroborate (TIPS-Eth-ArN) in our case. Chemical deprotection of the triisopropylsilyl function resulted in propargyl-terminated Au/rGO electrodes to which azidomethylferrocene was chemically linked using the Cu(I) catalyzed “click” chemistry.
Highlights
Accurate analysis of the presence of disease-specific biomarkers in biological fluids remains of great importance in clinical settings [1] and electrochemical sensors can reach that goal by converting a chemical or a biological response into a processable and quantifiable electrochemical signal [2]
We evaluate the effect of applied electrical current and applied voltage on the electrochemical behavior of electrophoretically deposited reduced graphene oxide (rGO) on gold thin film electrodes
It is based on a two-step process in which, after electrophoretic deposition (EPD) at 2.5 V for 5 min, the full reduction of graphene oxide (GO) to rGO is obtained by immersion into hydrazine vapor for 4 h
Summary
Accurate analysis of the presence of disease-specific biomarkers in biological fluids remains of great importance in clinical settings [1] and electrochemical sensors can reach that goal by converting a chemical or a biological response into a processable and quantifiable electrochemical signal [2]. Graphene and its related derivatives have generated great expectations as a transducing platform in biosensing, due to their good mechanical properties accompanied by biocompatibility, electrical conductivity and fast charge transfer kinetics [3,4,5,6]. Covalent and non-covalent strategies have been employed, including amide bond formation and π–π interactions, among others [7,8,9], to integrate surface functionalities and ligands onto graphene-based transducers. The development of these approaches depends on having robust graphene-coated interfaces at hand. The ability of EPD to be applied to different materials and to control the thickness of Surfaces 2019, 2, 193–204; doi:10.3390/surfaces2010015 www.mdpi.com/journal/surfaces
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
