DEVELOPMENT OF A VOLTAMMETRIC METHOD FOR THE SIMULTANEOUS DETERMINATION OF PESTICIDES IN SURFACE WATER USING A COMPOSITE ELECTRODE

• Published in: Química Nova 2024-01, Vol.47 (10)
• Main Authors: Barros Ferreira da Silva, Gleiciane, Ferreira Amaral, Mateus, Perin Bezerra, Felipe, Terezo, Ailton José, Castilho, Marilza
• Format: Article
• Language: English
• Subjects: carbendazim; carbofuran; CHEMISTRY, MULTIDISCIPLINARY; diuron; polycaprolactone
• ISSN: 0100-4042; 1678-7064; 1678-7064
• DOI: 10.21577/0100-4042.20240062

A method was developed and validated for the simultaneous quantification of pesticides carbendazim (CBZ), diuron (DI) and carbofuran (CF) in surface water using a sustainable, handmade, and low-cost composite electrode (CE) based on graphite and polycaprolactone (PCL). The cyclic voltammetric (CV) results showed a quasi-reversible oxidation peak for CBZ around +0.76 V, and an irreversible oxidation peak for DI and CF at +0.88 and +1.32 V, respectively. Under optimized conditions, the anodic peak currents were proportional over ranges of 5.0-1059.0 µg L-1 for the binary analysis of CBZ and DI, with detection limits of 4.0 and 18.0 µg L-1, and limits of quantitation of 13.0 and 55.0 µg L-1, respectively. The proposed electrochemical method also exhibited good repeatability (n = 10) and intermediate precision (n = 3), with a relative standard deviation of 5%. In addition, the method successfully determined CBZ and DI in surface water samples without any sample pretreatment. Comparison with the reference chromatographic method ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) showed no significant differences at a 95% confidence level, demonstrating the applicability of the method. Additionally, the composite electrode offers advantages such as low cost, easy manufacturing, and simple operation.