Electrochemical Sensors Based on Gold Nanoparticles for the Detection of Pesticides in Aerosol Phase
Pesticide, aerosol phase, golda nanoparticles
The intensive use of pesticides in Brazilian agriculture, although fundamental for crop productivity and protection, raises serious environmental and public health concerns due to soil, water, and air contamination, as well as occupational exposure. Conventional detection methods, such as chromatography and mass spectrometry, are highly reliable but require complex infrastructure, high costs, and long analysis times. In this scenario, electrochemical sensors emerge as a promising alternative, especially when integrated with nanomaterials such as gold nanoparticles (AuNPs), which offer high surface area, excellent electrical conductivity, and electrocatalytic properties. Despite significant advances in liquid matrices, the detection of pesticides in the aerosol phase remains underexplored, representing a relevant scientific and technological gap. The aim of this work is to develop electrochemical sensors based on screen-printed electrodes modified with gold nanoparticles for the detection of pesticides in aerosols, focusing on compounds such as Chlorpyrifos and 2,4-D. The specific objectives include the synthesis and physicochemical characterization of AuNPs, the controlled modification of the electrode surface, the morphological and electrochemical characterization of the system, and the evaluation of its analytical performance toward pesticides in both aqueous and aerosol phases. The methodology involves the synthesis of AuNPs using the Turkevich method, their characterization by DLS, UV-Vis, FTIR, and SEM, and the modification of screen-printed electrodes through controlled nanoparticle deposition. Electrochemical performance will be evaluated using techniques such as cyclic voltammetry and square-wave voltammetry. To simulate aerosol application, an experimental prototype for controlled dispersion will be developed, enabling sensor validation under real drift conditions. The developed sensor is expected to exhibit high sensitivity, selectivity, and stability toward organophosphorus pesticides and other target compounds, providing a rapid, portable, and low-cost platform for environmental monitoring. In addition to filling the current gap in gas-phase detection, the study may contribute to reducing human exposure to toxic pesticides and support public policies for environmental control, in line with the demand for more effective and sustainable technologies.