Simple, Miniaturized, Adaptable, Robust and Transportable (SMART) 3D-printed electrochemical cell: A friendly tool for on-site and forensic analysis

In this work, we introduce the SMART-EC3D (Simple to mount, Miniaturized, Adaptable to several electrodes, Robust and Transportable 3D-printed electrochemical cell). This device consists of a lid with a mini solution reservoir (volume between 100 and 1000 mu L) promptly attached through strong magnets to a base containing an adjustable bolt. This innovative and user-friendly configuration ensures the compatibility of the cell with any planar working electrode without solution leakage or electrode rupture. The cell was printed using different materials for FDM (ABS, PLA and PETG) and DLP (resin), which exhibited excellent stability in several supporting electrolytes (acid, basic and aqueous-organic). To demonstrate the versatility of SMART-EC3D for forensic analysis, we performed electrochemical screening of some seized illicit drugs (MDMA, LSD and 25I-NBOH) using typical working electrodes (gold, glassy carbon and boron-doped diamond, respectively) and a direct-on-solid screening protocol for the detection of the tadalafil in seized samples using a low-cost 3D-printed-based carbon electrode. Additionally, the determination of sildenafil citrate and paracetamol in pharmaceutical tablets using promising low-cost electrodes (graphite sheet and laser induced graphene, respectively) was demonstrated as examples of quantitative analysis. The fully portable system (SMART-EC3D plus wireless potentiostat and smartphone) has great potential for on-site electroanalyses and forensic applications.