An Electrochemically Synthesized Nanoporous Copper Microsensor for Highly Sensitive and Selective Determination of Glyphosate

Author(s)

Regiart, Matias ^[1] ; Kumar, Abhishek ^{[1, 2]} ; Goncalves, Josue M. ^[3] ; Silva Junior, Gilberto J. ^[1] ; Masini, Jorge Cesar ^[4] ; Angnes, Lucio ^[3] ; Bertotti, Mauro ^[1]

Affiliation

^[1] Univ Sao Paulo, Inst Chem, Lab Sensores Eletroquim & Metodos Eletroanalit, Ave Prof Lineu Prestes 748, BR-05513970 Sao Paulo, SP - Brazil

^[2] Univ Bourgogne Franche Comte, UMR CNRS 6302, ICMUB, 9 Ave Alain Savary, F-21078 Dijon - France

^[3] Univ Sao Paulo, Inst Chem, Lab Automacao & Instrumentacao Analit, Dept Fundamental Chem, Ave Prof Lineu Prestes 748, BR-05513970 Sao Paulo, SP - Brazil

^[4] Univ Sao Paulo, Inst Chem, Lab Quim Analit Ambiental, Dept Fundamental Chem, Ave Prof Lineu Prestes 748, BR-05513970 Sao Paulo, SP - Brazil

• Document type: Journal article
• Source: CHEMELECTROCHEM; v. 7, n. 7, p. 1558-1566, APR 1 2020.
• Web of Science Citations: 10

Abstract

A nanoporous copper (NPC) film was electrodeposited on a copper microelectrode, and the generated platform was investigated for electrochemical sensing of glyphosate (Glyp). The as-deposited NPC film was highly pure and crystalline according to results of energy dispersive spectroscopy and X-ray diffraction experiments, respectively. Scanning electron microscopy images confirm the NPC films possess a highly porous morphology containing dendrite fractals, and the electrodeposition parameters, particularly potential (E-d) and time (t(d)), exert a remarkable influence on the structure of the films. Such changes in the NPC morphology with E-d and t(d) were also correlated with the electrochemical behavior investigated by cyclic voltammetry. In the presence of Glyp, the anodic oxidation is facilitated because copper ions diffuse easily through the pores of the NPC film and form a complex with the analyte at the electrode interface. On the other hand, as the amount of copper oxides decreases due to the formation of soluble Cu(II) complex with Glyp, less current is obtained during the reverse scan, allowing a relationship between the decrease in the cathodic current and the Glyp concentration to be established. The optimized NPC-modified Cu microelectrode showed very high sensitivity (14 nA nmol(-1) L), low detection limit (4 nmol L-1), excellent reproducibility, and selective response for Glyp. The applicability of the sensor was demonstrated by detecting Glyp in river water samples. (AU)

• FAPESP's process: 18/16896-7 - Development of amperometric and impedimetric sensors based on double hydroxides of nickel and vanadium (alpha-NixV1-x(OH)2) and their nanocomposites with expandable graphite/graphene
• Grantee: Josué Martins Gonçalves
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 19/14418-3 - Electrochemical sensors for water quality monitoring
• Grantee: Gilberto Jose Silva Junior
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• FAPESP's process: 18/08782-1 - Miniaturized and integrated chemical sensors: new fabrication platforms for biological, clinical and environmental applications
• Grantee: Mauro Bertotti
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 19/06293-6 - Investigations in biological systems by using miniaturized electrochemical sensors
• Grantee: Daniel Matias Gaston Regiart
• Support Opportunities: Scholarships in Brazil - Post-Doctoral