A Binghamton University research team has manufactured a new ingestible electronic device.
The new device, called a “biobattery,” was developed to assist in capturing images and information that is difficult to obtain from the small intestine. According to Seokheun “Sean” Choi, a professor in the department of electrical and computer engineering at the Thomas J. Watson College of Engineering and Applied Science, the biobattery capsules — also known as ingestible electronic capsules — were designed to offer therapeutic and health diagnostic applications.
Choi discussed the purpose of his research and how stable power supply plays a critical role in the performance of these biobattery capsules. He explained that the small intestine lacks potential energy sources that could generate long-lasting power, but microbial fuel cells (MFCs), which Choi described as “fuel ingestible electronics,” hold enough power when the small intestine maintains a steady temperature and neutral pH.
“Those conditions and the constant supply of nutrient-rich organics are a perfect environment for the bacteria to generate long-lasting power,” Choi wrote in an email. “Although previous small-scale MFCs have demonstrated many promising applications, little is known about the potential for generating power in the human gut environment. The overall objective of this project was to generate practical and longstanding microbial power in the small intestine. Given that the non-human microbial cells inhabiting bodies outnumber human cells by at least a factor of 10, the harvested power produced by microbial cells is a way to fuel ingestible electronics.”
Other researchers on this project are Maryam Rezaie and Zahra Rafiee, second-year graduate students pursuing Ph.Ds. in electrical engineering. Rezaie explained how the capsules function in terms of collecting information for health data. Once ingested, the capsule captures bacteria and generates power that supports therapies through drug delivery, electrical stimulation and biopsy.
“Our ultimate biobattery will use in-vivo human gut bacteria,” Rezaie wrote in an email. “So while the capsule moves down the GI tract, it captures bacteria to generate power for the integrated applications. Or, the bioelectricity generated from the gut bacteria can be used as a diagnostic signal to understand the human gastrointestinal health. Given that we have successfully developed an ingestible microbial fuel cell (MFC) for the first time, this technology possesses immense potential as a viable option for the next generation of ingestible devices.”
Rezaie and Rafiee assisted Choi on his research by gathering information that led to the development of a three-dimensional printing capsule that underwent several trials. According to Rezaie, various ingestible devices have been proposed throughout the years, but toxic battery materials and potential mucosal injury created complications concerning the use of ingestible electronics. As a result, the team uses exoelectrogenic bacteria to generate electricity in the GI tract, which serves as the main source of energy.
Choi further explained the challenges that came with finding a reliable energy source that could generate long-lasting power in the small intestine.
“This work is part of a global effort to enable a next-generation of smart, stand-alone and long-lived, ingestible electronics that serve as practical clinical tools for diagnostics and therapy in the gastrointestinal (GI) tract,” Choi said. “While there are many ambient energy resources available in the human body to provide various implantable electronics with sustainable power, the GI tract contains extremely harsh conditions with few potential energy sources. The performance of the wireless power transfer significantly depends on the uncontrollable position and orientation of the devices while it is challenging to secure reliable and practical energy resources from thermal gradients and mechanical movement in the small intestine.”
According to Choi, the microbial energy harvesting methods in the small intestine are significantly more realizable and can provide superior self-sustaining features with long-term stability. This allows for a constant supply of nutrient-rich organics and creates a perfect environment for bacteria to generate long-lasting power. Choi and his team said the research is still ongoing as they continue to develop other microbial energy harvesting devices for portable, wearable and self-sustainable environmental applications.
Madelyn Hoskins, a sophomore majoring in biology, shared her thoughts about the ingestible capsules.
“I think research into biological matters is incredibly important,” Hoskins said. “Science is always changing, and new things are always being discovered. It’s vital to continue to research biological matters”
Gwendolyn Oh, a freshman majoring in computer science, said she is interested in learning more about devices that can monitor health diagnostics.
“This is really interesting research with the potential of a huge medical breakthrough,” Oh said. “I’m curious to know more about how the technology will work inside of people.”