Paper-based and soft materials to advance electrochemical sensors

The development of electrochemical sensors is at a turning point. The traditional rigid designs are constantly limited in point-of-care applications due to high cost, rigidity, and poor biocompatibility. The increasing need of detection/monitoring outside of the lab walls requires a radical rethinking: sensors designed for decentralized deployment, capable of embedding within environmental or biological systems, and eventually functioning directly at the point-of-contact. However, two key breakthroughs have fundamentally transformed electrochemical sensor development. To begin with, microfluidics on paper relies on natural capillary movement of cellulose fibers to provide liquid flow, and second, soft materials that are flexible and biocompatible. This convergence enables the emergence of a new category of wearable and implantable sensors capable of operating continuously within physiological systems, providing real-time data about the conditions that define health outcomes. Rather than treating paper and soft materials solely as supports for electrode patterning, this Perspective discusses them as active material platforms that govern fluid handling, electrode interfacing, mechanical compliance, reagent storage, and device translation. This transformation symbolizes core growth of point-of-need capability. Moving ahead, the current developments in substrate engineering and electrode development provide the technical framework of the next frontier. In the future, these combined technologies will grow into practical implementation, which will completely transform the way humanity views diagnostics/monitoring in the world.