Wireless Power Transfer to Millimeter-Sized Gastrointestinal Electronics Validated in a Swine Model.
Wireless Power Transfer to Millimeter-Sized Gastrointestinal Electronics Validated in a Swine Model.
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DOI：
10.1038/srep46745
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发表时间：
2017-04-27
影响因子：
4.6
通讯作者：
Traverso G
中科院分区：
文献类型：
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作者：
Abid A;O'Brien JM;Bensel T;Cleveland C;Booth L;Smith BR;Langer R;Traverso G
长期放置在胃肠道（GI）中的电子设备有可能改变临床评估和治疗。部署这种胃驻留电子设备的一个挑战是难以在不使用电池的情况下为毫米大小的电子设备供电，这损害了生物相容性和长期驻留。我们研究了利用中场无线供电将电力从体外传输到胃肠道沿着不同位置的电子设备的可行性。使用模拟和离体测量，我们设计了能够在1.2 GHz的组织中有效运行的中场天线。然后在五只麻醉猪体内对这些天线进行了体内表征，将一根天线放置在体外，另一根天线放置在内窥镜下的体内食道、胃和结肠处。在测试的动物中，当将体外功率分别耦合到食道、胃和结肠时，体内平均传输效率分别为-41.2、-36.1和-34.6 dB。这相当于在各个位置的天线接收到37.5 μW、123 μW和173 μW的功率水平，同时将辐射暴露水平保持在安全阈值以下。这些功率水平足以从身体外部为一系列医疗设备无线供电。
Electronic devices placed in the gastrointestinal (GI) tract for prolonged periods have the potential to transform clinical evaluation and treatment. One challenge to the deployment of such gastroresident electronics is the difficulty in powering millimeter-sized electronics devices without using batteries, which compromise biocompatibility and long-term residence. We examined the feasibility of leveraging mid-field wireless powering to transfer power from outside of the body to electronics at various locations along the GI tract. Using simulations and ex vivo measurements, we designed mid-field antennas capable of operating efficiently in tissue at 1.2 GHz. These antennas were then characterized in vivo in five anesthetized pigs, by placing one antenna outside the body, and the other antenna inside the body endoscopically, at the esophagus, stomach, and colon. Across the animals tested, mean transmission efficiencies of −41.2, −36.1, and −34.6 dB were achieved in vivo while coupling power from outside the body to the esophagus, stomach, and colon, respectively. This corresponds to power levels of 37.5 μW, 123 μW and 173 μW received by antennas in the respective locations, while keeping radiation exposure levels below safety thresholds. These power levels are sufficient to wirelessly power a range of medical devices from outside of the body.