3D打印（或称增材制造）已从20世纪80年代生产塑料原型发展到如今制造喷气发动机部件、牙科植入物甚至建筑物。德克萨斯州休斯敦莱斯大学的Yong Lin Kong及其同事在《科学进展》上发表的一项新研究介绍了一种将电子电路直接打印到敏感基底（包括活体组织）上的方法。这一发展可能为无线监测患者状况的医疗植入物、先进的计算机化药丸以及其他医疗创新铺平道路。

尽管使用含有导电铜、银或金纳米颗粒的电子墨水打印电路并不新鲜，但传统方法需要熔炉加热或激光轰击等退火工艺来熔合颗粒。这种高热会损坏聚合物和生物组织等热敏材料。Kong博士的团队克服了这一限制，开发了一种使用聚焦微波选择性地仅加热墨水颗粒的技术。通过将微波束聚焦到宽度小于人类头发（直径小于百万分之两百米）的一个点上，他们成功地对墨水进行了退火，而没有伤害周围的敏感物质。

这种紧凑的技术可以整合到台式3D打印机中，使操作员能够通过调节微波束的功率来调整导电率，并直接在布线中创建电阻器等组件。关键的潜在应用包括将传感器嵌入实验室培养的心脏瓣膜和气管中，以进行实时监测和器官刺激，以及开发计算机化的诊断药丸。该团队通过在牛股骨、用于人类患者膝盖和臀部替代物的聚合物上打印应变计，以及在活体叶片上打印湿度传感器，展示了概念验证。

3D printing, or additive manufacturing, has evolved from producing plastic prototypes in the 1980s to manufacturing jet-engine parts, dental implants, and buildings today. A new study published in Science Advances by Yong Lin Kong and colleagues at Rice University introduces a method to print electronic circuits directly onto delicate substrates, including living tissues. This development could pave the way for medical implants that wirelessly monitor patient conditions, advanced computerized pills, and other medical innovations.

Although printing circuitry with electronic inks containing conductive copper, silver, or gold nanoparticles is not new, traditional methods require annealing processes like furnace heating or laser zapping to fuse the particles. This high heat damages heat-sensitive materials such as polymers and biological tissues. Dr. Kong's team overcame this limitation by developing a technique that uses focused microwaves to selectively heat only the ink particles. By focusing a microwave beam to a dot less than 200 millionths of a meter across—narrower than a human hair—they successfully annealed the ink without harming the surrounding delicate substances.

This compact technology can be integrated into desktop 3D printers, allowing operators to vary the microwave beam's power to adjust conductivity and create components like resistors directly within the wiring. Key potential applications include embedding sensors into lab-grown heart valves and tracheas for real-time monitoring and organ stimulation, as well as developing computerized diagnostic pills. The team demonstrated proof of concept by printing strain gauges onto cow femurs, knee/hip replacement polymers, and a humidity sensor onto a living leaf.

Source: Electronics can now be printed onto living tissues

Subtitle: From cow femurs to replacement hips and even living leaves

Dateline: 6月 25, 2026 05:55 上午