A BIONIC DESIGN WITH WING STRUCTURES TO ASSIST FLEXIBLE MICROELECTRODE IMPLANTATION

Microelectrodes and microprobes are promising tools to explore brains at the cellular level or restore function in the nervous system. While making electrodes ultra-small and flexible is a trend with many merits in biomedical implants, it also brings a considerable challenge to insert them successfully and efficiently due to the buckling and deflection of the electrodes. Similar problems also exist in nature, like mosquito proboscis behavior and Hymenoptera oviposition. They develop a series of mechanisms to overcome the problems, such as reducing effective length, increasing stress concentration, guide-assisted insertion, reciprocating penetration, etc. Based on these mechanisms, a bionic design is presented where two wing structures are attached to the planar-type neural probe. The principles and benefits of the design are elaborated, and prototype dummy probes are fabricated. Compression buckling tests and insertion tests are conducted on tissue phantom, showing that the bionic design can enhance the stiffness of the probe and reduce the deflection angle effectively, improving the accuracy and efficiency of probe implantation. The presented design opens new approaches for the development of novel flexible microelectrodes and microprobes.