Tiny Biodegradable Circuits for Releasing Painkillers Inside the Body
August 7, 2019 | EPFLEstimated reading time: 2 minutes
Patients fitted with an orthopedic prosthetic commonly experience a period of intense pain after surgery. In an effort to control the pain, surgeons inject painkillers into the tissue during the operation. When that wears off a day or two later, the patients are given morphine through a catheter placed near the spine. Yet catheters are not particularly comfortable, and the drugs spread throughout the body, affecting all organs.
Researchers in EPFL’s Microsystems Laboratory are now working on a biodegradable implant that would release a local anesthetic on-demand over several days. Not only would this implant reduce patients’ post-op discomfort, but there would be no need for further surgery to remove it. They developed a tiny biodegradable electronic circuit, made from magnesium, that could be heated wirelessly from outside the body.
Once integrated into the final device, the circuit will allow to release controlled amounts of anesthetic in a specific location over several days. After that, the implant will degrade safely inside the body. This research has been published in Advanced Functional Materials.
One Capsule with Several Reservoirs
The electronic circuit—a resonant circuit in the shape of a small spiral—is just a few microns thick. When exposed to an alternating electromagnetic field, the spiral resonator produces an electric current that creates heat.
The researchers’ end-goal is to pair the resonators with painkiller-filled capsules and then insert them into the tissue during surgery. The contents of the capsules could be released when an electromagnetic field sent from outside the body melts the capsule membrane.
“We’re at a key stage in our project, because we can now fabricate resonators that work at different wavelengths,” says Matthieu Rüegg, a PhD student and the study’s lead author. “That means we can release the contents of the capsules individually by selecting different frequencies.” The heat-and-release process should take less than a second.
A Novel Manufacturing Technique
The researchers had to get creative when it came time to manufacture their biodegradable resonators. “We immediately ruled out any fabrication process that involved contact with water, since magnesium dissolves in just a few seconds,” says Rüegg. They ended up shaping the magnesium by depositing it on a substrate and then showering it with ions. “That gave us more flexibility in the design stage,” he adds. They were eventually able to create some of the smallest magnesium resonators in the world: two microns thick, with a diameter of three millimeters.
The team’s invention is not quite ready for the operating room. “We still need to work on integrating the resonators into the final device and show that it’s possible to release drugs both in vitro and in vivo,” concludes Rüegg.
Suggested Items
American Made Advocacy: Going Beyond the CHIPS Act to Power American Manufacturing
03/26/2024 | Travis Kelly -- Column: American Made AdvocacyWhere have all the factories gone? A tour of America’s former bustling manufacturing communities is a stark reminder that, for the past three decades, we let the microelectronics manufacturing ecosystem disappear overseas, primarily to Asia. For decades, foreign competitors seeking to control critical markets played a long game. Government investment and subsidies were effective in undercutting U.S. and European companies. As other countries created this unfair competitive advantage in manufacturing, the know-how also migrated in their direction. This resulted in the serious workforce challenges the semiconductor and printed circuit board industries face today.
Dave Brooks Celebrates 25 Years at IEC USA
03/26/2024 | IECPlease join IEC (International Electronic Components) in congratulating Dave Brooks on 25 years of service and camaraderie. As one of the original members of the IEC USA team, Dave is a valuable contributor to IEC's continued success.
MacDermid Alpha Electronics Solutions’ New Book Now Available for Download
03/27/2024 | I-Connect007I-Connect007 is pleased to announce the launch of The Printed Circuit Assembler’s Guide to… Encapsulating Sustainability for Electronics by Beth Turner at MAES. The latest in a series of educational books published by I-Connect007, this book is an introductory guide to understanding encapsulation resins and a tool for application troubleshooting.
Green Circuits Unveils Innovative Stacked Capacitors Assembly Process
03/21/2024 | Green CircuitsGreen Circuits, a full-service Electronics Manufacturing Services (EMS) partner to leading OEMs, today announced a groundbreaking advancement in process engineering with the successful implementation of an innovative assembly technique for stacked capacitors.
Happy’s Tech Talk #26: Balancing the Density Equation
03/14/2024 | Happy Holden -- Column: Happy’s Tech TalkPrinted circuit design and layout is a creative process that has profound implications for electronic products. With the need for more parts on an assembly, or the trend to make things smaller to be portable or for faster speeds, the design process is a challenging one. The process is one of “balancing the density equation” (Figure 1) with considerations for certain boundary conditions like electrical and thermal performance. Unfortunately, many designers do not realize that there is a mathematical process to the layout of a printed circuit