Wireless Power Beamed Straight to Your Heart

A tiny, implantable cardiac device is powered by radio waves

2 min read
Wireless Power Beamed Straight to Your Heart

How many pacemakers can fit on the head of a pin? Just one. But that's pretty impressive if you think about it.

At Stanford University, a team of researchers has built a tiny, implantable cardiac device that measured less than a millimeter in radius. This proof-of-concept device (which didn't actually set the pace for the contraction of living heart muscles) could be so small because it didn't require batteries—instead, it was powered by radio waves transmitted from outside the body.

Lead researcher Ada Poon, an assistant professor of electrical engineering at Stanford, thinks that wireless power transfer could lead to smaller and more precise implantable medical devices, as well as swallow-able devices. For cardiac devices, wireless power could offer big improvements over pacemakers powered by bulky batteries that need to be replaced periodically via surgery. 

Poon's device, described in a paper published in the journal Applied Physics Letters, has an external transmitter that sends radio waves to a coil inside the body, creating enough current to power the tiny implant.

Her big advance was in figuring out what frequency of radio waves to use. Previously, researchers thought that only low-frequency radio waves could travel far enough through human tissue to power an implanted device, but these low-frequency waves required large, impractical coils. Poon's team discovered that high-frequency radio waves, which require only a very small coil, could travel much deeper into the body than anyone realized. The image above shows power delivery to a human heart via low-frequency (left) and high-frequency (right) transmitters. 

Poon's been a busy researcher. We last covered her work in February, when she unveiled a tiny chip that could, theoretically, be propelled and steered through the human body using external magnetic fields. Poon said that chip was suitable for the human digestive tract and larger blood vessels, and could lead to devices for drug delivery and diagnostic imaging. 

Image: John Ho, Stanford Engineering

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This CAD Program Can Design New Organisms

Genetic engineers have a powerful new tool to write and edit DNA code

11 min read
A photo showing machinery in a lab

Foundries such as the Edinburgh Genome Foundry assemble fragments of synthetic DNA and send them to labs for testing in cells.

Edinburgh Genome Foundry, University of Edinburgh

In the next decade, medical science may finally advance cures for some of the most complex diseases that plague humanity. Many diseases are caused by mutations in the human genome, which can either be inherited from our parents (such as in cystic fibrosis), or acquired during life, such as most types of cancer. For some of these conditions, medical researchers have identified the exact mutations that lead to disease; but in many more, they're still seeking answers. And without understanding the cause of a problem, it's pretty tough to find a cure.

We believe that a key enabling technology in this quest is a computer-aided design (CAD) program for genome editing, which our organization is launching this week at the Genome Project-write (GP-write) conference.

With this CAD program, medical researchers will be able to quickly design hundreds of different genomes with any combination of mutations and send the genetic code to a company that manufactures strings of DNA. Those fragments of synthesized DNA can then be sent to a foundry for assembly, and finally to a lab where the designed genomes can be tested in cells. Based on how the cells grow, researchers can use the CAD program to iterate with a new batch of redesigned genomes, sharing data for collaborative efforts. Enabling fast redesign of thousands of variants can only be achieved through automation; at that scale, researchers just might identify the combinations of mutations that are causing genetic diseases. This is the first critical R&D step toward finding cures.

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