Novel energy harvesting tech could reshape medical devices

文章作者：艾米丽·牛顿（Emily Newton）

多年来，医疗设备已经走了很长一段路，挽救了生命并帮助人们管理疾病。但是，一个主要缺点是他们的电池需要更换或充电。由于研究人员通过能够收获能源收获的设备取得进展，可能并非如此之多，因此为开发人员和需要产品的人带来了新的选择。

消除对起搏器电池更换的需求

Millions of people rely on pacemakers and other implantable cardiac devices to keep their hearts functioning normally. However, those items need battery replacements every decade or sooner. Replacing the battery requires the patient to undergo surgery. Besides the expenses associated with those ongoing procedures, any operation carries the risk of complications.

Researchers at Dartmouth University hope to use the heart’s energy to power pacemakers. If that idea becomes a reality, it could eliminate those scheduled surgeries to replace batteries.

The team’s goal was to harness the kinetic energy of the pacemaker’s lead wire that gets attached to the heart. They used a polymer piezoelectric film called PVDF thatturns mechanical motion into electricity如果设计有多孔结构。2019年，研究人员在开发和测试方面取得了足够的进步，他们认为该设备距离商业可用性已经五年了。

尽管尚未上市，但对于评估哪些产品最适合其患者需求的医疗设备制造商和医生来说，此功能可能是一个有吸引力的卖点。该角钱尺寸的发明适合现有的起搏器，并且还可以扩展提供未来的功能，例如实时监控。

Developing More Devices That Are Safe to Use in the Body

设计一个小鬼的持久的挑战之一lantable medical device is finding a material durable enough to withstand the harsh and varied conditions inside the body without introducing toxic elements or other complications.

能源收集的压电选择提供了确定整体电力输出的广泛因素。有些是固有的，像频率常数of the piezoelectric element. Extrinsic factors, such as acceleration and amplitude of the movement, matter too. As you might imagine, materials selection is also critical when capitalizing on this effect.

Many materials used for piezoelectric projects are naturally occurring, such as enamel, bone and crystal. However, another obstacle in biocompatible materials selection is that they’re often too stiff to conform to the body’s surfaces. A medical device may need flexibility similar to a bandage, depending on its purpose.

Building Biocompatible, Piezoelectricity-Powered Wafers

Bioengineersrecently developed可用于产生电刺激以加快骨折和伤口愈合并通过保持肌肉张力来帮助中风患者的“压电晶片”。

在这种情况下，赖氨酸是一种压电发电机。由生物相容性聚合物制成的壳围绕着赖氨酸。赖氨酸和聚合物的化学相互作用将赖氨酸定位为弯曲时产生电流的晶体结构。研究人员认为，他们的创造最终可以让某人的自然运动加速康复过程。

这些设备的另一个巨大优势是它们是可生物降解的。到目前为止，团队已经用啮齿动物的腿和胸部测试了晶圆。然后，他们在产物自然溶解后进行了实验实验，这没有对啮齿动物的有害作用的证据。

If innovations like these become available to the public, medical device makers should strongly consider highlighting the biodegradability aspect. Some patients may understandably be wary of having devices put into their bodies if their physicians suggest it. However, if they know the gadgets will break down after use and feature nontoxic materials, they should feel more open to the idea.

Creating Low-Profile Wearable Medical Devices

这里覆盖的设备遍布体内。外部可见的产品需要具体考虑，以使其更有可能出售。舒适是鼓励用户采用并增加他们像往常一样生活的机会的主要必要性。

That’s especially true when the goal is to capture details that may not be evident during medical appointments. For example, Finnish researchers designed aconnected jumpsuit for babies that trackstheir movements and monitors development. In that case, it was vital that the wearable didn’t annoy the infants or cause discomfort.

Feeling self-conscious is an issue for many adults. It’s vital to prioritize wearable medical devices that are easy to hide or otherwise won’t make someone feel embarrassed when using the product at college, work or another public place.

这就是为什么工程师开发了人们可以在棒球帽下佩戴的能量收集设备的原因。这是毛囊stimulation device that triggers regrowth来自休眠结构。这种方法使用纳米发育仪，这些纳米发电机在将低频电脉冲传输到头皮之前，从佩戴者的正常运动中被动地收集能量。

无毛小鼠的实验室测试表明，该设备以及在秃头药物中发现的两种化合物起作用。但是，这些产品不会引起不愉快的副作用，例如抑郁和性功能障碍。

Making Wearable Medical Trackers More Convenient

医疗保健提供者越来越多地使用连接的可穿戴医疗设备来跟踪从患者的心率到血糖水平的所有事物。这些产品是理想的物品，人们可以在没有问题的情况下连续穿着。实际上，大多数人需要定期充电，但是北卡罗来纳州立大学的团队希望用一种从人体热量获得能量的设备来克服该障碍。本发明是一种灵活的热电发生器（TEG）。以前使可弯曲的Tegs的大多数努力都无法执行僵化的设备。但是，研究人员进行了设计调整，并取得了令人印象深刻的结果。

They originally made a proof of concept TEG in2017。However, the engineers said an upgraded type announced in 2020 was closer to the efficiency provided by stiff devices. One of the components is EGaIn, a nontoxic alloy of gallium and indium. It provides stretchability plus electrical conductivity similar to metal.

Mehmet Ozturk, who worked on the project and coauthored a研究论文about it, explained, “The key here is using ahigh thermal conductivity silicone elastomer用石墨烯片和egain掺杂。弹性体提供了针对穿刺的机械鲁棒性，同时改善了设备的性能。使用这种弹性体使我们能够将热导率（传热速率）提高六次，从而改善了侧向热传播。”

能源收获打开令人兴奋的可能性

Wearable and implantable medical devices are increasingly common, whether they treat an ailment, accelerate the healing process or help physicians track a patient’s status. These products are especially beneficial if users do not need to go through the hassle of recharging or replacing their batteries. The examples here show what’s possible and illustrate why energy harvesting could be essential for making medical gadgets more valuable and practical.

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艾米丽·牛顿is a technology and industrial journalist who enjoys discovering how the IoT is impacting different industries. Emily is editor in chief of革命– an online magazine exploring trends in science, technology and industry.Subscribe向她的新闻通讯跟上最新消息。