Zirconium dioxide nanoparticles modified gold microelectrode for improved amperometric detection of ascorbic acid, 2,3-dihydroxybenzoic acid and pyrocatechol in flow-based analysis

13^th International Conference on Electrochemistry

May 27-28, 2019 | Barcelona, Spain

Muhammed Ariful Islam, Mostafa A. Atia, Parvez Mahbub, Mirek Macka  and Brett Paull

Australian Centre for Research on Separation Science (ACROSS), School of Natural Sciences, University of Tasmania, Australia
Institute for Sustainable Industries and Liveable Cities, Victoria University, Australia
Department of Chemistry and Biochemistry, Mendel University in Brno, Czech Republic
Central European Institute of Technology, Brno University of Technology, Czech Republic
ARC Training Centre for Portable Analytical Separation Technologies (ASTech), School of Natural Sciences, University of Tasmania, Australia

Posters & Accepted Abstracts: J Biosens Bioelectron

Abstract :

The modification of screen-printed gold microelectrodes (Au SPME) using zirconium dioxide nanoparticles (ZrO2 NPs) and termed as Zr-Au SPME, has been investigated for improved amperometric detection (AD) in flow-based analysis. The average size of ZrO2 NPs on Au SPME surface, calculated using a Gaussian distribution, was 22.5±7 nm. The redox behaviour of a test solute, ferrocyanide [Fe(CN)6]4-, on the bare-Au and Zr-Au SPME was initially investigated using cyclic voltammetry. The resulting voltammograms of the bare-Au and Zr-Au SPME were compared and the peak response (current) and effective surface area were 100% greater for the Zr-Au SPME. The AD performance of Zr-Au SPME was investigated for electroactive solutes in a standard LC platform. The limits of detection (LODs) of ascorbic acid, 2,3-dihydroxybenzoic acid and pyrocatechol were 0.09 μM, 0.04 μM, and 0.10 μM, respectively (RSD ~2.5 %, n=9, linearity r2 ~0.99 for concentration range 1-100 μM). LODs of electroactive solutes using Zr-Au SPME were 2â??5 times lower than the lowest LODs reported in the existing literature using microelectrodes. Compared to reported AD in a standard LC platform a three times reduction of baseline noise and a 4â??8% improvement in peak efficiency was achieved. The Zr-Au SPME demonstrated good repeatability and reproducibility, and a stability of approximately 8.5 hours in FIA and at least 45 days in a standard LC platform at 0.6 mL min-1.