A few decades ago, the technological boom revolutionized access to information, ushering in a new era of research possibilities. Electrochemical devices have recently emerged as a key scientific advancement utilizing electrochemistry principles to detect various chemical species. These versatile electrodes find applications in diverse fields, such as healthcare diagnostics and environmental monitoring. Modern designs have given rise to innovative manufacturing protocols, including screen and additive printing methods, for creating sophisticated 2D and 3D electrochemical devices. This perspective provides a comprehensive overview of the screen-printing and additive-printing protocols for constructing electrochemical devices. It is also informed that screen-printed sensors offer cost-effectiveness and ease of fabrication, although they may pose challenges due to the use of toxic volatile inks and limited design flexibility. On the other hand, additive manufacturing, especially the fused filament fabrication (or fused deposition modeling) strategies, allows for intricate three-dimensional sensor designs and rapid prototyping of customized equipment. However, the post-treatment processes and material selection can affect production costs. Despite their unique advantages and limitations, both printing techniques show promise for various applications, driving innovation in the field toward more advanced sensor designs. Finally, these advancements pave the way for improved sensor performance and expand possibilities for academic, environmental, and industrial applications. The future is full of exciting opportunities for state-of-the-art sensor technologies that will further improve our ability to detect and determine various substances in a wide range of environments as researchers continue to explore the many possibilities of electrochemical devices.

Heavy metals are the main pollutants present in aquatic environments and their presence in human organisms can lead to many different diseases. While many methods exist for analysis, colorimetric and electrochemistry are particularly attractive for on-site analysis and their integration on a single platform can improve multiplexed metals analysis. This report describes for the first time a “plug-and-play” (PnP) assembly for coupling a microfluidic paper-based device (μPAD) and a screen-printed electrochemical paper-based device (ePAD) using a vertical and reversible foldable mechanism for multiplexed detection of Fe, Ni, Cu, Zn, Cd and Pb in river water samples. The integration strategy was based on a reversible assembly, allowing the insertion of a pretreatment zone to minimize potential chemical interfering agents and providing a better control of the aspirated sample volume as well as to a lower sample evaporation rate. In comparison with lateral flow and electrochemical assays performed using independent devices, the integrated prototype proved that the reversible coupling mechanism does not interfere on the analytical performance (95% confidence interval). The limit of detection (LOD) values calculated for metals determined varied from 0.1 to 0.3 mg L⁻¹ (colorimetric) and from 0.9 to 10.5 μg L⁻¹ (electrochemical). When compared to other integrated devices based on horizontal designs, the use of a foldable coupling mechanism offered linear response in a lower concentration range and better LOD values for Fe, Ni and Cu. The proposed method successfully measured heavy metals in river water samples with concentrations ranging from 16 to 786 μg L⁻¹, with recovery studies ranging from 76 to 121%. The new method also showed good correlation with conventional atomic absorption spectroscopic methods (95% significance level). Thus, the integration of μPADs and ePADs by a vertical folding mechanism was efficient for multiplexed heavy metal analysis and could be exploited for environmental monitoring.