Imagine a future where electronic implants are replaced with smart ingestible devices. According to researchers, that might be possible in the next five years with the help of a biodegradable "smart pill" that's powered by the body's own chemistry.
"We're interested in converting the world of implantable medical devices into ingestible medical devices. So we're taking all the sophisticated electronics that are used in things like pacemakers and drug delivery systems and converting them into ingestible formats," Chris Bettinger, a biopolymer researcher at the material science department at Carnegie Mellon University, told me over the phone.
In a paper published today in the journal Trends in Biotechnology, the researchers focus on developing new materials that could be used in the creation of a non-toxic "smart pill" that is easy on the body. Bettinger envisions that these devices could be used for controlled release of drugs, and as ingestible sensors for monitoring people's physiology.
Instead of using regular battery tech, the researchers also turned to naturally occurring chemicals to power their smart pill. The researchers found that melanin pigments in people's hair and eyes could be used as an electrode material that buoys the device inside the body.
"We're interested in answering this question: what would an ingestible medical device need to have in terms of a material profile? What will the power supply be? If we're designing, batteries what will they be made of?" asked Bettinger.
According to Bettinger, the idea of a smart pill has been around since the 1970s. However, in previous studies and trials, such pills have contained electronics that once ingested, either proved toxic to the body, or just got stuck in the body's GI tract. Bettinger cited ingestible cameras as an example of things that have become lodged in people's bodies before.
Bettinger said that the best way of avoiding such incidents is to use materials that biodegrade. "We want to use flexible elastomer (a stretchy polymer network) that can stretch, bend, and degrade," he said. "That would have a better chance of passing through your GI tract without getting stuck."
Ultimately, the researchers want to fabricate medical devices that are cost-effective and that take cues from the body's chemical signals.
"We want to create smart devices that don't just release drugs arbitrarily, but that release specific dosages at specific times—as and when your body needs it," said Bettinger.