Exploring the Mechanical Durability and Electroanalytical Performance of 3D-Printed Multi-Material Sensors for Rapid On-Site Screening of Nimesulide in Industrial Sewage

This work demonstrates the fabrication, mechano-electric, and electrochemical characterisation of a sustainable, fully 3D-printed electrochemical cell (3DPEC) for electroanalytical applications in static and flow conditions. The two-electrode cell comprises carbon black (CB)-filled polylactic acid (PLA) electrodes sealed within insulating PLA walls. The failure behaviour and electric resistance profiles of additive-manufactured multi-material joints with different geometries subjected to tensile load were investigated to explore the possible effect of flow pressure stresses on sensor accuracy. The digital imaging correlation technique was applied to determine the strain distribution during the test. A practical and straightforward route for 3DPEC post-processing treatment was proposed to enhance the electrochemically active surface area (ESA). Finally, we present a proof-of-concept determination of nimesulide, an anti-inflammatory drug, directly in industrial sewage, with a detection limit of 1 nM. The presented approach demonstrates the capability of low-cost, on-demand, and fully customisable 3D-printed cells for rapid environmental screening with high sensitivity.