When you hear the term, ‘Electronics’ you might think of a motherboard, a robot, a tangle of wires, and other metal and plastic devices that beep and whirr.
Science may have changed that paradigm forever – there are now electronic devices that break up after they are no longer necessary for internal monitoring, so your body can absorb the materials without harm.
Dissolvable Silicon to Save Lives
Silicon is a semiconducting material, and common in microchips and other technology. Think Silicon Valley – it’s named for the use of silicon in computing. Silicon is also biodegradable. (Don’t confuse silicon, a natural semiconductor material, with synthetic silicone, which is an insulator – it does not conduct electricity.)
Dr. John A. Rogers, professor of materials science and engineering at the University of Illinois at Urbana-Champaign, and Dr. Wilson Ray, professor of neurological surgery at the Washington University School of Medicine in St. Louis, led a team of researchers to harness the power of modern computing power to internally monitor brain injuries. What makes this set of monitoring tools different? They planned to use a new array of materials, to reduce the trauma of inserting and retrieving monitors. These materials break up within the body once they are no longer necessary – that means no second surgery to retrieve the sensor.
Dr. Rogers took the time to answer some questions about this new technology, and offer unique insight into the research. You can read the paper and the press release via links in the Resources section to the right.
How Long Does a Dissolvable Sensor Work?
The device is silicon based, with metal foil that breaks up a bit more slowly, but all materials absorb into the body over time. The time it takes for the sensor to be absorbed is dependent on how robust the encapsulating material is, so theoretically, it’s possible to use one of these devices to monitor an area for more than a few days, if it’s packaged to last longer.
Dr. Rogers explains, “We are demonstrating advanced versions of these devices that can operate for up to several weeks – even beyond the period of clinical relevance for this particular application.”
Researching and Developing Dissolvable Electronics
This is research that took more than a few lab experiments – the team has been working on this concept for years. According to Dr. Rogers, “We have been studying the basic science of each of a full complement of materials options for these systems, from the semiconductor, to the metals and dielectrics of the circuits and sensors, to the substrates and encapsulation/packaging layers.
Our first paper on ‘transient’ silicon electronics appeared in 2012, with some very basic demos of isolated components. From 2013-2014 we identified and studied carefully a complete set of materials for generic functions in bioresorbable transient electronics.
Over the last 1.5 years or so, we focused on the TBI application, with our neurosurgeon collaborators at Washington University. This paper describes the first result of a functional bioresorbable electronic technology designed to address a clinical need.”
Dissolvable Devices: Challenges
This research requires a high level of quality control. The sensors must not only work well, but also break down effectively and within the required time-frame. Dr. Rogers tells us, “The challenge is essentially one in materials science and device design. The basic molecular architecture of the materials, and the means by which they are used to construct devices determines the functional lifetime – but as you say, there are big challenges in producing a device with rock solid, stable operation when all of its constituent materials must dissolve, completely, away to yield biocompatible end products. We have found ways to address all of these, and other, challenges.”
Bioresorbable Materials: The Future
So what’s next for this team of researchers? According to Dr. Rogers, “As for future work, we are doing three things:
(a) enhancing the stable operational lifetime, from several days, to several weeks, via incorporation of advanced bioresorbable materials and new device designs
(b) moving to larger animal models to demonstrate the technology, as the first steps toward clinical studies in humans, which might occur ~2-3 years from now, and
(c) including capabilities in actuation (e.g. electrical or thermal stimulation), and other interventional function (e.g. drug release), to create a kind of ‘bioresorbable bioelectronics medicine’.
Operation in closed feedback control using co-integrated bioresorbable sensors is a goal.
Technology Advances Every Day
Researchers are gathering data on new types of technology, and new applications of existing technology, every day. Bioresorbable bioelectronics is something that is sure to spark interest from the medical community and techies alike.