A copper-based metal-organic framework/reduced graphene oxide-modified electrode for electrochemical detection of paraquat

Author(s)

Wachholz Junior, Dagwin ; Deroco, Patricia Batista ; Kubota, Lauro Tatsuo

• Document type: Journal article
• Source: Microchimica Acta; v. 189, n. 8, p. 12-pg., 2022-08-01.

Abstract

An electrochemical device using copper-based metalorganic franmeworks (MOF) associated with reduced graphene oxide to improve the charge transfer, stability, and adherence of the structures on the surface of the electrodes was developed. The syntheses of these materials were confirmed using scanning electron microscopy, thermogravimetric analysis, X-ray diffraction, Fourier transform infrared and Raman spectroscopy. For the first time, this type of sensor was applied to a systematic study to understand the action mechanism of MOFs and reduced graphene oxide in the electrochemical detection of paraquat pesticide. Under optimized conditions, paraquat was detected in standard solutions by differential pulse voltammetry (- 0.8 to - 0.3 V vs Ag/AgCl), achieving a linear response range between 0.30 and 5.00 mu mol L-1. The limits of detection and quantification were 50.0 nmol L-1 and 150.0 nmol L-1, respectively. We assessed the accuracy of the proposed device to determine paraquat in water and human blood serum samples by recovery study, obtaining recovery values ranging from 98 to 104%. Furthermore, the selectivity of the proposed electrode for paraquat detection was evaluated against various interferences, demonstrating their promising application in environmental analysis. (AU)

• FAPESP's process: 21/09706-0 - Development of a CRISPR/Cas-based electrochemical biosensor for T-Cell Leukemia virus (HTLV-1) and Staphylococcus Aureus bacteria detection with point-of-care devices
• Grantee: Dagwin Wachholz Júnior
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 19/00166-2 - Paper-Based Electrochemical Biosensor for Traumatic Brain Injury detection
• Grantee: Patrícia Batista Deroco
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 13/22127-2 - Development of novel materials strategic for integrated analytical devices
• Grantee: Lauro Tatsuo Kubota
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 14/50867-3 - INCT 2014: National Institute of Science and Technology in Bioanalysis
• Grantee: Marco Aurelio Zezzi Arruda
• Support Opportunities: Research Projects - Thematic Grants