Biomedical Roundup: 3 Advances Reconciling Size, Convenience, & Accuracy

Healthcare technology has long wrestled with trade-offs: brain probes that risk damaging tissue, implants that require bulky batteries and wires, and diagnostic tools that depend on invasive blood tests. This year, research teams from Dartmouth University, Rice University, and Penn State have released prototypes that tackle these challenges head-on.

Researchers at Rice University. Image used courtesy of Rice University

Each group has developed a device designed to operate more safely, more efficiently, and with greater potential to personalize treatment.

Dartmouth Rethinks 3D Neural Probes

Traditional neural probes are flat silicon arrays that struggle to interface with the brain’s three-dimensional structure. This mismatch limits both the quality of data collected and the stability of long-term implants. Researchers at Dartmouth addressed the problem with what they call a “rolling-of-soft-electronics” (ROSE) approach. By rolling flexible electronic materials into a 3D form, similar to a Swiss roll, the team created probes with multiple shanks and electrodes along their length.

Schematic of a monolithic 3D neural ROSE probe. Image used courtesy of the University of Dartmouth

These probes can reach deeper tissue layers while reducing stress on surrounding cells. Polymer-based materials make them softer and more compatible with brain motion than rigid silicon, lowering the risk of scarring that often disrupts signal quality. Beyond serving as powerful research tools, the design opens possibilities for medical use. Applications could include motor prosthetics for paralyzed patients or visual neuroprostheses that stimulate the visual cortex to restore perception. The ability to scale the design means one device can be tailored for different neurological conditions.

Rice University Makes Miniature Wireless Implant Networks

While implantable medical devices such as pacemakers and stimulators are lifesaving, they remain constrained by wires and batteries. More electrodes can mean better coverage of the heart or spinal cord, but also more surgical complexity. A team at Rice University has developed an alternative: a distributed network of miniature wireless implants, each about the size of a grain of rice, that can be powered and programmed by a single external transmitter.

The magnetoelectric nodes beside a pencil for scale. Image used courtesy of Joshua Woods and Rice University

The implants use magnetoelectric materials that convert magnetic fields into electricity. This energy is harvested from an external device and used to deliver targeted pulses to tissue. By embedding unique digital identifiers into each signal, the system allows individual implants to respond selectively, making them independently addressable. Tests in large animal models showed the system could synchronize multiple heart pacing sites or activate distinct spinal cord regions to engage specific muscle groups. Efficiency even improved as more devices were added, a surprising benefit of the magnetoelectric design.

The long-term vision is a customizable platform for cardiac resynchronization, spinal cord rehabilitation, and neurological therapies. Removing wires and batteries would simplify surgery, while networks of implants could one day form closed-loop systems that sense and respond to the body in real time.

Penn State Devises Breath-Based Diabetes Sensor

Diabetes is widespread yet often undiagnosed until damage has already occurred. Current screening requires blood samples or sweat analysis, both of which are inconvenient. A Penn State team has built a sensor that can identify diabetes and prediabetes in minutes using a simple breath sample. The device detects acetone, a volatile compound that rises above a threshold of 1.8 parts per million in people with diabetes.

A sensor to help diagnose diabetes and prediabetes. Image used courtesy of Penn State

The sensor’s sensitivity comes from a composite of laser-induced graphene and zinc oxide. The porous graphene provides a large surface area for gas capture, while the zinc oxide improves selectivity for acetone over other breath components. To overcome interference from moisture in exhaled air, the researchers added a molecular sieve layer that blocks water but allows acetone through. The result is a device with a detection limit as low as four parts per billion, fast response times, and the ability to function in humid conditions.

Right now, the prototype requires exhaling into a bag for testing, but the team is working on direct-use versions that could be embedded in a mask or handheld device. Beyond diagnostics, monitoring breath acetone could reveal how metabolism shifts with diet or exercise, giving the sensor applications in everyday health tracking.

Steps Toward Less Invasive Medicine

The three projects target very different conditions, yet they share the common goal of doing more with less disruption. At Dartmouth, flexible 3D probes are being designed to read brain activity without causing as much tissue stress. At Rice, a set of tiny wireless implants could replace the wires and batteries that make current devices bulky. At Penn State, a small sensor turns a breath sample into a quick diabetes check. Taken together, these efforts suggest a future where diagnosis and treatment feel less like surgery and more like routine care.