Wireless, battery-free, fully implantable optoelectronic devices and systems for tissue oxygen sensing

Real-time monitoring of tissue oxygenation within the nervous system is imperative for advancements in neuroscience research and the improvement of clinical diagnostics. Unlike blood oxygenation levels, the partial pressure of oxygen in brain tissue (PbtO₂) offers a more direct insight into the localized neural activities and metabolic states. Here, we present a microscale optoelectronic probe for the wireless, real-time monitoring of in vivo partial brain tissue oxygen (PbtO₂) levels. This probe measures local PbtO₂ concentrations via the luminescent quenching mechanism of phosphorescent dyes. An integrated light-emitting diode (LED) and photodetector are used to generate and capture the optical signals. To facilitate capturing and wirelessly transmitting PbtO₂ signals, the device includes miniaturized electronic circuits that can be powered by a battery or an inductive coil. In vitro and in vivo experiments demonstrate the ability to dynamically record oxygen partial pressure (pO₂), offering novel exploration opportunities in neuroscience research and clinical applications.