Desenvolvimento de dispositivos de baixo custo impressos em 3D para o monitoramento voltamétrico do herbicida diuron em amostras de bebidas e água

Abstract

This work presents the development of low-cost electrochemical sensors produced by 3D printing using recycled materials, applied to the determination of the herbicide diuron (DIU) in different matrices. The electrodes were constructed using a conductive composite material containing graphite and recycled polymer, acrylonitrile butadiene styrene (ABS), in accordance with the principles of sustainability, green chemistry, and circular economy. The optimization of the electrode composition allowed the fabrication of devices with high sensitivity and selectivity. Additionally, a modification was performed by incorporating metal-organic frameworks (MOFs) and gold nanoparticles, aiming to enhance the electroanalytical response. The sensors were applied in voltammetric and amperometric methods for the determination of DIU. The 3D-CPE electrode was employed for the analysis of sugarcane juice and cachaça samples by square wave voltammetry (SWV), with linear ranges between 0.25–2.5 and 5–20 µmol L⁻¹, and a detection limit (LOD) of 0.07 µmol L⁻¹. It was also used for the analysis of cachaça samples by flow injection analysis with amperometric detection (FIA-AMP), showing a linear range between 10–50 µmol L⁻¹ and an LOD of 1.05 µmol L⁻¹. The modified sensor, 3D-CPE/MIL-53(Al)-TDC/AuNP, was applied for the determination of DIU by differential pulse voltammetry (DPV) in tap water, river water, and lake water samples, showing a linear range of 0.99–19.2 µmol L⁻¹ and an LOD of 0.04 µmol L⁻¹. The recovery values obtained ranged from 97 to 107%, confirming the precision of the methods developed. Additionally, a method was developed capable of simultaneously quantifying DIU and carbendazim (CBZ) by DPV, with linear ranges of 2–10 µmol L⁻¹ for both. The calculated LOD was 0.52 µmol L⁻¹ for DIU and 1.07 µmol L⁻¹ for CBZ. This method shows potential for application in environmental monitoring or quality control analyses. The results demonstrate that the proposed sensors are efficient, sustainable, and affordable, representing a promising alternative for monitoring emerging contaminants in different matrices, with potential contribution to sustainable development goals.