Nanoporous Gold Microelectrode: A Novel Sensing Platform for Highly Sensitive and Selective Determination of Arsenic (III) using Anodic Stripping Voltammetry

Author(s)

Orellana Jaramillo, Dario Xavier ^{[1, 2]} ; Sukeri, Anandhakumar ^[1] ; Saravia, Lucas P. H. ^[1] ; Espinoza-Montero, Patricio Javier ^[2] ; Bertotti, Mauro ^[1]

Affiliation

^[1] Univ Sao Paulo, Inst Chem, Dept Fundamental Chem, Av Prof Lineu Prestes 748, Sao Paulo, SP - Brazil

^[2] Escuela Politecn Nacl Ladron Guevara E11 253, Ctr Invest & Control Ambiental, Dept Ingn Civil & Ambiental, POB 17-01-2759, Quito - Ecuador

• Document type: Journal article
• Source: Electroanalysis; v. 29, n. 10, p. 2316-2322, OCT 2017.
• Web of Science Citations: 11

Abstract

A home-made gold microelectrode (Au-E) was fabricated and its surface was modified with nanoporous gold structures via a facile electrochemical approach (anodization followed by electrochemical reduction method). The fabricated nanoporous Au microelectrode (NPG-E) was used as a sensor probe for the determination of As(III) in 1.0 mol L-1 HCl solution using square wave anodic stripping voltammetry (SWASV) technique. Field emission scanning electron microscopy (FE-SEM) and cyclic voltammetry were used to characterize the surface morphology and assess the electrochemical surface area and the roughness factor of the NPG-mu E. SWASVs recorded with the NPG-E in As(III) solutions indicated linear behaviour in the concentration ranges of 10-200 mu g L-1 and 2-30 mu g L-1, with regression coefficients of 0.996 and 0.999 at a deposition time of 120s, respectively. The limit of detection (LOD) was found to be 0.62 mu g L-1 with high sensitivity of 29.75 mu A (mu gL(-1))(-1) cm(-2). Repeatability and reproducibility were also examined and values were determined as 3.2% and 9.0%. Negligible interference from major interfering copper ion was noticed, revealing the excellent anti-interference property of the proposed sensing platform. The developed NPG-mu E was successfully used for As(III) determination in tap water samples. (AU)

• FAPESP's process: 14/15215-5 - Fabrication and characterization of nanoelectrodes for use in Scanning Electrochemical Microscopy (SECM): fundamental and analytical applications
• Grantee: Sukeri Anandhakumar
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 15/20776-9 - Fabrication of nanometric probes for the study of biochemical processes by using Scanning Electrochemical Microscopy
• Grantee: Mauro Bertotti
• Support Opportunities: Regular Research Grants