Prolonged energy harvesting for ingestible devices

Abstract

Ingestible electronics have revolutionized the standard of care for a variety of health conditions. Extending the capacity and safety of these devices, and reducing the costs of powering them, could enable broad deployment of prolonged monitoring systems for patients. Although prior biocompatible power harvesting systems for in vivo use have demonstrated short minute-long bursts of power from the stomach, not much is known about the capacity to power electronics in the longer term and throughout the gastrointestinal tract. Here, we report the design and operation of an energy-harvesting galvanic cell for continuous in vivo temperature sensing and wireless communication. The device delivered an average power of 0.23 μW per mm2 of electrode area for an average of 6.1 days of temperature measurements in the gastrointestinal tract of pigs. This power-harvesting cell has the capacity to provide power for prolonged periods of time to the next generation of ingestible electronic devices located in the gastrointestinal tract.

A human pilot trial of ingestible electronic capsules capable of sensing different gases in the gut

“…The temperature sensor and transmission circuit can operate for nearly 30 days, as they only require micro-amp level currents, providing an important safety feature to monitor the excretion of the capsule out of volunteer's bodies. More advanced methods such as energy harvesting from the liquid of the gut can be used for prolonging the lifetime of the capsule even further 37 . The capsules were fully calibrated prior to trials to a range of gas mixture, pressure, humidity and temperature.…”

Materials Strategies and Device Architectures of Emerging Power Supply Devices for Implantable Bioelectronics

“…Biocompatible metallic electrodes (e.g., Mg and Zn) with high energy density in the thin‐film or thin‐foil format, acting as the anodes represent one widely adopted strategy to achieve both biocompatible and flexible battery implants . Coupled with biocompatible thin‐film cathode materials (e.g., platinum (Pt), copper (Cu), gold (Au), polypyrrole (PPy)), the constructed galvanic cells can offer electrical power through the electrochemical dissolution process of the active materials (Mg, Zn).…”

Materialien und Strukturen für schluckbare elektromechanische medizinische Funktionseinheiten

“…In frühen Beispielen wurden Fe-Au-Elektrodenpaare eingesetzt, [2] während modernere Funktionseinheiten Zn-Cu [32] oder Mg-Cu verwenden, die bei Bedarf hçhere Spannungen produzieren. In frühen Beispielen wurden Fe-Au-Elektrodenpaare eingesetzt, [2] während modernere Funktionseinheiten Zn-Cu [32] oder Mg-Cu verwenden, die bei Bedarf hçhere Spannungen produzieren.…”

“…[33] In neueren galvanischen Zellen wurden Mg-Anoden mit Kathoden aus Mo,Woder Fe gekoppelt, um spezifische Leistungen von 45 bis 75 mWcm À2 zu erzeugen. [32] Diese Funktionseinheit produzierte eine mittlere flächenbezogene spezifische Leistung von 23 mWcm À2 für 6.1 Tage.M g-Anoden kçnnen auch mit redoxaktiven Polymerkathoden und biologisch abbaubaren Tr ägermaterialien gekoppelt werden, um hybride elektrochemische Zellen zu erzeugen. [34] Diese jahrhundertealte Te chnik wurde verfeinert und kürzlich in einer schluckbaren Funktionseinheit installiert, die periodisch Daten übermittelt oder Wirkstoffe aus einem bordeigenen Reservoir abgibt.…”