Accounts in 3D-Printed Electrochemical Sensors: Towards Monitoring of Environmental Pollutants

Heavy metal ions, small organic molecules and inorganic pollutants are some environmentally hazardous compounds that negatively impact the ecosystem and public health, owing to their high toxicity, persistency and bioaccumulation. This makes it essential to develop rapid, simple, low-cost and sensitive devices for in situ monitoring of these toxic contaminants. In this sense, 3D printing is an additive manufacturing technique, which is transforming the way that materials are turned into functional devices by prototyping bespoke 3D materials via layer-by-layer deposition. This technology can offer enormous potential to environmental devices, where electrochemical sensing platforms have been on the rise, as they offer decentralized and tailored fabrication of on-demand, low-cost, at-point-of-use systems. Although this research is still in an early stage, this Minireview aims to point out the most widely used additive manufacturing technology and materials for 3D-printed electrode fabrication, as well as some pivotal activation procedural steps necessary to enhance their electroanalytical capabilities. Indeed, the potential of 3D-printed electrochemical sensors to monitor a range of important hazardous pollutants in aqueous samples is reported, visualizing the future of this technology to develop integrated low-cost analytical electronic systems for direct environmental detection in remote areas of the globe.