Researchers have developed a novel type of battery, designed for “transient electronics” and inspired by the self-destructing devices in Mission Impossible: dissolvable power sources driven by probiotics.
“Transient electronics can be used for biomedical and environmental applications, but they must disintegrate in a biosafe manner,” corresponding author Seokheun Choi explains, evoking the Mission Impossible plot device of briefing recordings that self-destruct upon listening. “You don’t want to have toxic residues inside your body. That type of device is called ‘bioresorbable electronics.’ For transient or bioresorbable electronics, the key challenge is the power source — but most power sources, like lithium-ion batteries, include toxic material.”
Researchers have developed a fully-dissolvable, body-safe battery for “transient electronics” — powered by probiotics. (📷: Rezaie et al)
That was never a problem for Ethan Hunt, but for real-world uses — particularly in, on, or around the human body — it’s a problem that needs to be solved. The solution: a dissolvable, bio-friendly battery powered using probiotics. “We used well-known electricity-producing bacteria, which is within biosafety level one, so it is safe — but we were not sure what would happen if these bacteria were released into nature,” Choi explains. “But whenever I made presentations at conferences, people would ask: ‘So, you are using bacteria? Can we safely use that?'”
The team’s work focused on finding a safe, biocompatible probiotic strain that would also produce electricity, with first author Maryam Rezaie leading the project to a blend of 15 probiotics. Initially, the results were disheartening — but a change in design for the electrode of the probiotic battery proved key, delivering usable amounts of power by providing a rough, porous surface on which the bacteria could attach and thrive.
The batteries are made using bio-compatible materials, and could be safely eaten. (📷: Rezaie et al)
“Other research must be done,” Choi admits. “We used probiotic blends, but I want to study individually which ones have the extra electric genes, and how synergistic interactions can improve the power generation. Also, in this research we developed in a single unit of a biobattery. I want to contact them in series or parallel to improve the power.”
The team’s work, which included the production of a prototype capable of outputting 4µW at an open-circuit voltage of 0.65V, has been published in the journal Small under open-access terms.