Various multichannel silicon electrodes have been developed for stimulating and recording in the central nervous system of experimental animals. These electrodes can be used in their planar form or can be assembled into 3-D structures for volume interaction with tissue. However, bio-compatibility issues arise concerning the introduction of any electrode into living tissue. From earlier observations, we noticed that the neuronal cells had a tendency to adhere to the chronically implanted silicon substrate. Routine microtechnique became an obstacle when attempting to section the implanted and embedded electrode. Most often, this was attempted by passing a stainless steel blade through paraffin, or plastic embedded tissue, resulting in disrupting the tissue material interface. We needed to develop a reproducible procedure which preserved the integrity of this interface for future LM and confocal microscopic studies.

In order to preserve the electrode/tissue interface, we used the Exakt microgrinding/micropolishing technique, where the electrode/brain block was embedded in Technovit 7200 resin and cut with a diamond impregnated band saw.