Edible batteries that power 'smart' pills to organs soon

Imagine a "smart pill" that can sense problems in your intestines and actively release an appropriate drug. But the problem is that for this to happen we need some degradable source right within the gut to power it to the affected body area.

Now, professor Christopher Bettinger of Carnegie Mellon University has presented a novel vision for creating safe, consumable medical electronics powered by the charged ions within our digestive tract.

Currently, there are ingestible cameras for gastro-intestinal surgeries as well as sensors attached to medications used to study how drugs are broken down in the body.

"The primary risk is the intrinsic toxicity of these digestible materials. For example, if the battery gets mechanically lodged in the gastrointestinal (GI) tract. But that is a known risk. In fact, there is very little unknown risk in these kinds of devices," said Bettinger, professor in materials science and engineering.

Bettinger is also exploring how minerals in a healthy diet, or even pigments from the skin or eye, could be used in bioelectronics.

Ingestible devices that are used now are powered by off-the-shelf batteries, just like what you would find in a watch.

Bettinger challenges whether a segmented battery is necessary as, he contends, the natural liquids within the body can be the electrolytes that move current through the device.

Labs have already proven that electronics built using this method can disintegrate in water after two-three months.

"The breakfast you ate this morning is only in your GI tract for about 20 hours. All you need is a battery that can do its job for 20 hours and then, if anything happens, it can just degrade away," he proposed.

There is also evidence that manufacturing biologically-inspired "smart pills" can be cost-effective and pass regulatory approval.

Ingestible medical devices and even 3D-printed pills have been given the green light for patient use in recent years.

One of the reasons medications cost so much is that only a small percentage of a pill actually makes it to where it needs to be used in the body.

"If an electronic pill can make better use of expensive medications, then the amount needed for each patient can be reduced," Bettinger argued.

"If we can engineer devices that get the most mileage out of existing drugs, then that is a very attractive value proposition. I believe these devices can be tested in patients within the next 5-10 years," he said in a paper that appeared in the journal Trends in Biotechnology.