Soft and Stretchable Nanomembrane-Based Electrode Arrays for High-Fidelity Electrophysiological Signal Recording of the Gastrointestinal Tract

Recording electrophysiological signals from the gastrointestinal (GI) tract is critical for advancing our understanding of GI function, disorders, and the gut-brain axis. However, the dynamic motility and extremely soft nature of GI tissues make it challenging to obtain high-quality signals from multichannel electrode arrays. To address the mechanical mismatch between conventional electronics and biological tissues, there is a need for highly compliant, conductive materials and devices. In response to these challenges, we present a novel approach for engineering soft, stretchable electronic interfaces that combine high conductivity with strain stability, even after patterning into small features. Our method involves stacking multiple layers of gold nanomembranes embedded in an elastomer substrate. These stacked nanomembranes exhibit high conductivity (>20,000 S/cm), low resistance (0.5 Ω/■), and exceptional stretchability (~500%). The nanomembranes, patterned via laser cutting into fine features as small as 50 µm, maintained both structural integrity and electrical performance under strain. To further enhance sensing performance, the electrodes were coated with platinum particles to reduce impedance. These engineered materials were integrated into multichannel electrode arrays, which were then mounted onto the stomach and colon of anesthetized mice, successfully capturing high signal-to-noise ratio local electromyographic (EMG) signals from multiple locations. This material-driven advancement in soft, conductive electronics opens new opportunities for precise mapping of GI electrical activity and deeper insights into related disorders.