The recording of neural activity in large populations of single neurons within the brain over extended periods is vital for advancing our understanding of neural circuits and developing innovative medical device-based therapies. A team of interdisciplinary researchers from the Harvard John A.
Brain
Paulson School of Engineering and Applied Sciences (SEAS), in collaboration with The University of Texas at Austin, MIT, and Axoft, Inc., has recently introduced a breakthrough soft implantable device equipped with dozens of sensors. This device demonstrates the ability to stably record single-neuron activity in the brain for months, addressing the tradeoff between high-resolution information and the duration of recording or stimulation performance.
Published in Nature Nanotechnology, the research represents a significant stride in the field of brain-electronics interfaces, offering single-cell resolution with enhanced biocompatibility compared to conventional materials. The soft implantable device is designed to revolutionize bioelectronics for neural recording and stimulation, as well as for the development of brain-computer interfaces.
Paul Le Floch, the first author of the paper and former graduate student at SEAS, now serving as the CEO of Axoft, Inc., highlighted the device’s potential to overcome challenges in high-resolution data rate and longevity. The team utilized fluorinated elastomers, akin to materials like Teflon, known for resilience, stability in biofluids, and compatibility with microfabrication techniques. These fluorinated materials were integrated with stacks of soft microelectrodes, totaling 64 sensors, resulting in a probe that is 10,000 times softer than conventional flexible probes made from engineering plastics.
The device’s in vivo demonstration involved recording neural information from the brains and spinal cords of mice over several months, showcasing its durability and long-term stability in real-world conditions. Harvard’s Office of Technology Development has protected the intellectual property associated with this research and licensed the technology to Axoft for further development.
The interdisciplinary collaboration, involving expertise in biology, electrical engineering, materials science, and mechanical and chemical engineering, underscores the complexity of designing novel neural probes and interfaces. Lead researcher Liu emphasized the feasibility of designing elastomers for long-term-stable neural interfaces, expanding the possibilities for future designs in the field. This research marks a significant contribution to advancing neurotechnology and its potential applications in medical and therapeutic contexts.
