Sometimes Mother Nature has a material solution that is superior to what a chemist might cook up. And that appears to be the case for Carnegie Mellon University's Chris Bettinger and Jay Whitacre, who found that cuttlefish ink provides just the right chemistry and nanostructure to power tiny, ingested electronic devices.
Bettinger, an assistant professor of materials science and biomedical engineering, and Whitacre, an associate professor of materials science and engineering, have been pioneers when it comes to finding battery substances that could be digested, allowing for the powering of medical devices that might also be eaten.
|Carnegie Mellon researchers found that naturally occurring melanins derived from cuttlefish ink exhibit higher charge storage capacity compared to other synthetic melanin derivatives when used as anode materials. (Art provided by Carnegie Mellon University.)|
"In addition to notifying doctors that pills have been taken, smart pills can make it possible for patients to take certain medications orally which must currently be injected because they're destroyed by stomach acid. Common treatments for osteoporosis and arthritis, for instance, must be injected. A smart device can protect the medication until it has passed through the stomach and release it in the intestine."
Digestible batteries might also have potential to power medical devices could be implanted in the body and used temporarily until they dissolve, without ever requiring a second surgery for retrieval.
|See Kurt (Chip) Breitenkamp, PhD, managing scientist for polymer science and materials chemistry at Exponent Inc., chair a Learning Lab on new capabilities of bioresorbable polymers on Thursday, February 13, at MD&M West in Anaheim, CA.|
When it came to producing such a digestible battery, Bettinger and Whitacre have already reported some success creating edible power sources using materials found in a daily diet. But they still needed to find the optimal pigment-based anodes to include in their edible sodium-ion batteries.
They ended up finding out that naturally occurring melanins derived from cuttlefish ink exhibit higher charge storage capacity compared to other synthetic melanin derivatives when used as anode materials, according to a paper appearing in the Dec. 9 online edition of the Proceedings of the National Academy of Sciences. (Cuttlefish are close relatives of squid. Thinly sliced squid, breaded and fried, is called calamari.)
"Using natural materials in energy storage devices increases the likelihood for use in powering devices that operate in sensitive environments such as the human body," Bettinger said in a December press release from Carnegie Mellon.
Natural materials have often inspired researchers searching for novel materials.
The natural world offers plenty when it comes to inspiration. There are, for instance, researchers who are trying to replicate the gecko's ability to climb walls (using the Van der Wals property) and researchers trying to replicate mussels' ability to cling to rocks in the ocean.
There are even scientists trying to give humans the ability to regenerate limbs in the way that newts and many other animals do.