Novel diamond shuttle to deliver flexible neural probe with reduced tissue compression

The ability to deliver flexible biosensors through the toughest membranes of the central and peripheral nervous system is an important challenge in neuroscience and neural engineering. Bioelectronic devices implanted through dura mater and thick epineurium would ideally create minimal compression and acute damage as they reach the neurons of interest. We demonstrate that a three-dimensional diamond shuttle can be easily made with a vertical support to deliver ultra-compliant polymer microelectrodes (4.5-µm thick) through dura mater and thick epineurium. The diamond shuttle has 54% less cross-sectional area than an equivalently stiff silicon shuttle, which we simulated will result in a 37% reduction in blood vessel damage. We also discovered that higher frequency oscillation of the shuttle (200 Hz) significantly reduced tissue compression regardless of the insertion speed, while slow speeds also independently reduced tissue compression. Insertion and recording performance are demonstrated in rat and feline models, but the large design space of these tools are suitable for research in a variety of animal models and nervous system targets. Neuroscience: Novel diamond shuttle for delivering flexible neural probes A new three-dimensional diamond shuttle can deliver bioelectronic devices through tough membranes of the central and peripheral nervous system to reach neurons of interest with minimal compression and acute damage. The accuracy of implantable biosensors is dependent on minimum damage to nervous system circuitry. Kyounghwan Na at the University of Michigan in the United States and colleagues succeeded in developing a diamond shuttle with 54% less cross-sectional area than an equivalently stiff silicon shuttle, resulting in a 37% reduction in blood vessel damage when modeled. The higher-frequency oscillation of the new shuttle reduced tissue compression irrespective of the insertion speed. The authors conducted their tests using rat and cat models, but they believe the large design space of their easily made shuttle has considerable potential for application in a variety of animal models and nervous system targets.