A 3D-printed electrode made from recycled plastic, graphite, and carbon black detects the drug ketamine in beverages faster and more sensitively than a commercial 3D-printed electrode. After a simple polishing step, the recycled-material electrode showed better electrical performance: a peak-to-peak separation of 130 mV versus 759 mV, lower charge transfer resistance (1.04 kΩ vs. 9.62 kΩ), and a higher heterogeneous rate constant. It detected ketamine across a concentration range of 10 to 250 μmol L-1 with a sensitivity of 0.024 μA μmol L-1 and a detection limit of 0.7 μmol L-1. Recovery rates in spiked drinks (wine, beer, water, vodka) ranged from 82% to 115%.
A fully 3D-printed electrochemical double cell (3D-EDC) allows selective detection of LSD and two phenethylamine classes (NBOHs and NBOMes) in seized blotter papers. The system can use two working electrodes (boron-doped diamond and 3D-printed graphite) or two pH levels (4.0 and 12.0) with a graphite electrode, enabling fast, robust, and sensitive analysis. The method shows good stability (relative standard deviation <9% for current and <5% for potential), a broad linear range (20-100 and 20-70 μmol L⁻¹), and a low limit of detection (1.0 μmol L⁻¹) for LSD quantification. This provides a practical, cost-effective on-site screening tool for forensic analysis.