In Vivo Wireless Sensors for Gut Microbiome Redox Monitoring

A perturbed gut microbiome has recently been linked with multiple disease processes, yet researchers currently lack tools that can provide
in vivo
, quantitative, and real-time insight into these processes and associated host-microbe interactions. We propose an
in vivo
wireless implant for monitoring gastrointestinal tract redox states using oxidation-reduction potentials (ORP). The implant is powered and conveniently interrogated via ultrasonic waves. We engineer the sensor electronics, electrodes, and encapsulation materials for robustness
in vivo
, and integrate them into an implant that endures autoclave sterilization and measures ORP for 12 days implanted in the cecum of a live rat. The presented implant platform paves the way for long-term experimental testing of biological hypotheses, offering new opportunities for understanding gut redox pathophysiology mechanisms, and facilitating translation to disease diagnosis and treatment applications.