Implantable biomedical devices -; like insulin pumps, pacemakers, and neurostimulators -; are becoming smaller and operating wireless technology, but hurdles remain for powering the next-generation implants. A novel wireless charging device created by Penn State researchers could dramatically advance the powering ability of implants while still being harmless for our bodies, the scientists said.
The novel device can yield energy from the magnetic field and ultrasound sources concurrently, altering this energy to electricity to power implants, the researchers informed in the journal Energy & Environmental Science. It is the primary device to harvest these dual-energy sources simultaneously with high effectiveness and function within the safety restrictions for human tissue, the team informed.
Utilizing this technology, battery-free bioelectronic devices may well shrink to millimeter-sized dimensions, making them effortlessly implantable and permitting distributed networks of sensors and actuators to monitor and operate physiological activity throughout the body. This would allow accurate and adaptive bioelectronic therapies with nominal risks or interference with daily events, according to the researchers.
More traditional implants like pacemakers are usually powered by batteries and charged using cables. However, the lifecycle of batteries is limited and surgery may be required to replace them, posing a danger of contamination or other medical difficulties.
Charging or directly powering implants wirelessly could increase their lifespan, the researchers said. However, conventional wireless charging technology utilized for cell phones and electric vehicles may not be perfect as implants continue to shrink.
The problem is that as you make these implants less hostile by making them smaller and smaller, the effectiveness of wireless charging becomes lower, said Mehdi Kiani, assistant professor of electrical engineering at Penn State and co-author of the research. To address this, it’s essential to increase the power. But the problem is that high-frequency electromagnetic waves might be damaging to the body.
Magnetic field and ultrasound energy functioning at lower frequencies are attractive choices for wirelessly powering or charging implants, according to scientists. Prior work by other researchers has focused on generating devices that can yield one of these sources of energy, but not at the same time, the researchers said. However, this single-source method may not deliver enough power to charge smaller impending medical implants.
Now we can merge two modalities in a single receiver, said Sumanta Kumar Karan, a postdoctoral scholar in the Department of Materials Science and Engineering at Penn State and the principal author of the paper. This can surpass any of the individual modalities since now we have two sources of energy. We can surge the power by a factor of four, which is significant.
The devices utilize a two-step procedure for altering magnetic field energy to electricity. One layer is magnetostrictive, which translates a magnetic field into stress, and the other is piezoelectric, which translates stress, or vibrations, into an electric field. The blend allows the device to turn a magnetic field into an electric current.
And the piezoelectric coating also can at the same time alter ultrasound energy into an electric current, the scientists said.
We have combined these bases of energy in a similar footprint, and we can create adequate power that can be used to prepare the things that next-generation implants will be requested to do, Poudel said. And we can do this without tissue damage.
Technology also has insinuations for powering tech like wireless sensor networks in smart buildings. These systems ensure things like monitoring energy and operational outlines and use that data for remotely regulating control systems, the researchers said.
Other Penn State scientists involved were Andrew Patterson, professor in the Department of Veterinary and Biomedical Sciences; Anitha Vijay, investigative technologist; and Sujay Hosur, doctoral applicant. Kai Wang and Rammohan Sriramdas, past assistant study professors at Penn State, and Shashank Priya, vice president for research at the University of Minnesota and ex-professor at Penn State also contributed.
The National Science Foundation supported this work. Some of the scientists in this paper established support from the DARPA MATRIX database and the Army RIF program.
