Overview of MasterSil 912Med
MasterSil 912Med is a silicone system that has been specially formulated for bonding, sealing, and coating, primarily for medical devices. It passes both USP Class VI testing and ISO 10993-5 cytotoxicity standards and resists many sterilization techniques, including gamma and other types of radiation, EtO, as well as some liquid sterilants. MasterSil 912Med bonds well to a wide variety of substrates upon curing and is suitable for many medical device applications, including re-implantable neural probes to track the neural activity of free-moving mice.
Application
Recording neural activity in freely-moving animals can yield information about how their brains operate under realistic conditions. To provide this information, Neuropixels probes have been developed to offer insights into the neural activity of free-moving mice by recording data from hundreds of neurons simultaneously. However, Neuropixels probes are generally single-use and cannot be re-implanted after an experiment. As these probes are expensive and only available in limited quantities, this leads to high costs during experiments. Explanting and then re-implanting the Neuropixels probes require careful probe design, in part due to the fragile nature of the shank, which typically breaks during explantation.
Researchers at Cold Spring Harbor Laboratory developed a so-called Apparatus to Mount Individual Electrodes (AMIE) to encase and protect onboard electronics in the probe during long-term free-moving experiments in mice. Although the AMIE was designed to allow the probe to be explanted from one mouse and then re-implanted in a second mouse, the shank often broke during explantation attempts. To prevent this, the authors found it necessary to use MasterSil 912Med to further secure the shank and enable re-implantation of the probe.
To read about the experiment's key parameters, requirements and results, download the full case study.
Download MasterSil 912Med case study
Reference
Juavinett, A. L.; Bekheet, G.; Churchland, A. K. Chronically Implanted Neuropixels Probes Enable High-Yield Recordings in Freely Moving Mice. Elife 2019, 8, e47188. https://doi.org/10.7554/eLife.47188.