Multisensing Patch Combining Printed Electrodes and Paper-Based Millifluidics for Sweat Monitoring During Electrodermal Activity Monitoring

Although electrodermal activity (EDA) is a well-established technique for monitoring psychophysical conditions, its widespread adoption is limited by signal reliability challenges, primarily the difficulty in discriminating rapid phasic variations from slow tonic changes driven by personal features and workload. To bridge this gap, we propose a novel hybrid approach combining printed conductive electrodes with a millifluidic porous system to enable sweat absorption and monitoring over time. A multisensing patch integrating inkjet-printed electrodes with a laser-cut paper-based millifluidic network was developed. After optimizing geometry, ink, and substrate, the patch was tested in laboratory and industrial settings with real users, comparing results against commercial pre-gelled electrodes. Findings demonstrated that combining silver-based ink with PEDOT:PSS provides superior sensitivity and repeatability, while Whatman Grade 3 paper ensures optimal linearity. In vivo tests suggested performances comparable to the standard EDA commercial electrodes in terms of Pearson correlation coefficient between tonic (0.82±0.09 ) and phasic (0.71±0.13 ) components and of similar number of skin conductance responses (SCRs) detected (Delta; SCR/min < 3). Overall, the proposed solution presents key innovative advantages in terms of complete customizability of the geometry, thus supporting the possibility to translate the approach to different wearables and personal protective equipment, representing a useful starting point for future physiological monitoring in a wide range of industrial workstations and operational conditions.