Introduction To Bioresorbable Batteries
Tiny dissolving batteries could power medical devices after being swallowed, revolutionizing the field of ingestible electronics. Researchers at MIT are developing a power source with an exit strategy built into its chemistry, allowing the batteries to break down into materials the body can absorb. This innovation has the potential to enable the creation of swallowable devices that can monitor the body, release medicine, or send information back out without the need for surgical removal of the battery.
Design And Mechanism Of The Batteries
The batteries are made from materials considered tolerable in small amounts, including magnesium and molybdenum trioxide, which form the anode and cathode, respectively. An ionic liquid gel acts as the electrolyte, allowing ions to move between the electrodes. The use of these materials makes the battery bioresorbable, meaning it can break down and be absorbed by the body. In an acidic solution resembling stomach fluid, the batteries worked normally for roughly three days before their output gradually weakened, with complete breakdown occurring within a few weeks.
Applications And Testing Of The Batteries
The researchers tested the batteries in two devices: one with a radio-frequency identification (RFID) tag that can transmit data from inside the body, and one that electrically stimulates the stomach to trigger the release of hunger-regulating hormones. In animal tests, the battery supported continuous stimulation for as long as three days, increasing ghrelin levels by about 50 percent. The team also packaged the batteries together with other fully biodegradable, non-toxic electronics inside gel capsules and tested them in pigs. An RFID-tracking device inside a swallowable gel capsule transmitted signals to a reader outside the pigs’ bodies.
Future Outlook And Implications
The potential payoff of this invention extends beyond the clinical, as degradable battery materials could also reduce the environmental burden of electronics that leave the body and enter sewage systems. Human testing is still ahead, with the researchers planning a clinical trial for the medication-tracking system, called SAFARI, expected to begin in about two years. While the battery's capacity is still low, the technology has promising implications for the development of temporary devices inside the gut that can avoid surgery to retrieve a conventional battery when the device is no longer needed.
Challenges And Limitations
One of the challenges faced by the researchers was finding materials that are both non-toxic and capable of producing a high enough voltage to power electronics. The use of magnesium and molybdenum trioxide as electrodes and a biodegradable ionic liquid as the electrolyte addressed this challenge. However, the battery's capacity is still a limitation, and further research is needed to increase its capacity and make it more promising for practical applications.
Conclusion And Future Directions
The development of bioresorbable batteries is a significant step forward in the field of ingestible electronics. With further research and testing, these batteries could enable the creation of a wide range of medical devices that can be safely swallowed and absorbed by the body. The potential benefits of this technology are substantial, and it will be exciting to see how it develops in the coming years.
Sources
This is an original synthesis by Qivorane based on reporting from the outlets below.
