A research team from Cold Spring Harbor Laboratory worked on new Neuropixels probes that enable simultaneous recording of hundreds of neurons with remarkably high signal to noise in freely moving mice. They used biocompatible silicone MasterSil 912Med for adapting Neuropixels probes for chronically-implanted experiments. Here is a quote from their work:

“Mounting the probe. ... Using a needle, we applied a medical-grade clear silicon adhesive, MasterSil 912Med, to the base of the shank.”1

Sources:

1Chronically-implanted Neuropixels probes enable high yield recordings in freely moving mice. Juavinett, A.L., Bekheet, G., Churchland, A.K. Cold Spring Harbor Laboratory (Cold Spring Harbor, NY 11743). https://www.biorxiv.org/content/biorxiv/early/2018/09/05/406074.full.pdf