On-Site Electrochemical Detection of Sulfentrazone Using a Fully 3D-Printed Portable Sensing Platform

The widespread use of pesticides in agricultural activities has increased concerns regarding environmental contamination and occupational exposure, particularly through dermal contact. In this work, we report a portable and low-cost electrochemical sensing platform for on-site monitoring of sulfentrazone (SFT), a herbicide extensively used in eucalyptus cultivation. The proposed device consists of a fully 3D-printed miniaturized electrochemical system fabricated by multi-material printing using conductive and non-conductive filaments, enabling accessible and decentralized analysis. SFT detection was performed by square-wave voltammetry (SWV), exhibiting a single irreversible oxidation peak at +0.86 V (pH 6.5). Under optimized conditions, the platform showed a linear response from 1.1 to 101.1 μmol L^-1, with a limit of detection of 0.50 μmol L^-1 (obtained through IUPAC recommendations). The proposed approach demonstrated satisfactory accuracy and precision in spiked tap water samples, with recoveries ranging from 100 to 103% and RSD values ≤ 2.9% (n = 3). Additionally, the platform was successfully applied to porcine skin samples as a model for detecting dermal contamination, yielding recoveries between 81 and 111%. The combination of additive manufacturing and electrochemical sensing provides a simple, reliable, and field-deployable strategy for SFT monitoring in environmental and biological matrices, highlighting the potential of fully 3D-printed analytical platforms for occupational and environmental applications.