Voltammetric sensing of glyphosate in different samples using carbon paste electrode modified with biochar and copper(II) hexadecafluoro-29H,31 phtalocyanine complex

Author(s)

Wong, Ademar ^{[1, 2]} ; de Lima, Douglas Goncalves ^[1] ; Ferreira, Priscila Alves ^[3] ; Khan, Sabir ^[1] ; Bezerra da Silva, Rodrigo Amorim ^[4] ; Brito de Faria, Jorge Luis ^[5] ; Taboada Sotomayor, Maria Del Pilar ^{[1, 2]}

Affiliation

^[1] State Univ Sao Paulo UNESP, Inst Chem, Dept Analyt Chem, BR-14801970 Araraquara, SP - Brazil

^[2] Natl Inst Alternat Technol Detect Toxicol Evaluat, BR-14801970 Araraquara, SP - Brazil

^[3] Fed Univ Mato Grosso do Dul, Inst Chem, BR-79074460 Campo Grande, MS - Brazil

^[4] Univ Fed Uberlandia, Inst Chem, BR-38500000 Monte Carmelo, MG - Brazil

^[5] Univ Fed Mato Grosso, Inst Phys, Campo Grande, MS - Brazil

• Document type: Journal article
• Source: Journal of Applied Electrochemistry; v. 51, n. 5, p. 761-768, MAY 2021.
• Web of Science Citations: 1

Abstract

This paper reports the development of carbon paste electrode (CPE) modified with biochar (BC) and copper(II) 1,2,3,4,8,9,10,11,15,16,17,18,22,23,24,25-hexadecafluoro-29H,31 phtalocyanine (CuHPc) used for the sensitive and selective detection of glyphosate in different matrices. The characterizations of the materials were performed using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and Fourier-transform infrared spectroscopy (FTIR). The analytical efficiency of the modified electrodes (CuHPc/CPE and BC-CuHPc/CPE) used for glyphosate detection was evaluated by square-wave voltammetry (SWV). The application of BC-CuHPc/CPE resulted in an improvement in the electron transfer process on the electrode surface, and this led to an outstanding increase of 100% in its current signal compared to CuHPc/CPE. Under optimized conditions, the BC-CuHPc/CPE sensor presented a linear concentration range of 0.3-4 mu mol L-1 and a limit of detection of 0.02 mu mol L-1. Interference analysis was conducted using different compounds that can be found in the environment including 2,4-D, atrazine, diuron, urea, and caffeine; the results obtained showed that the compounds did not exert any interference in the current peak of the glyphosate. The proposed method was applied for the determination of glyphosate in river water and food samples, where recovery rates of nearly 100% were obtained. The results demonstrate the accuracy and reliability of the proposed modified electrode. {[}GRAPHICS] . (AU)

• FAPESP's process: 19/00677-7 - RADes-MIP - preparation and synthesis of materials for development of rapid analysis devices for monitoring emerging pollutants using highly selective biomimetic polymers based on molecular printing technology
• Grantee: Maria Del Pilar Taboada Sotomayor
• Support Opportunities: Regular Research Grants