Syringe-injectable mesh electronics integrate seamlessly with minimal chronic immune response in the brain

Significance Seamless integration of electrical probes within neural tissue could substantially enhance their impact and open up new opportunities in neuroscience research through electronic therapeutics. This paper describes systematic studies of brain tissue behavior following implantation of a design for probes that can be precisely targeted to specific brain regions by syringe injection as in many biological species and have an ultraflexible open mesh structure similar to brain tissue itself. Studies of the chronic tissue response postimplantation demonstrate that these tissue-like probes do not elicit inflammation or scarring, in contrast to more conventional probes. Moreover, neurons were found to penetrate through the probes’ open mesh structure, thus demonstrating an unprecedented level of integration and compatibility with the brain circuitry.