The application of nano- and microfabricated devices based on silicon electronics technology is an emerging interdisciplinary area combining engineering and biology. The placement of electrically active probes in damaged or diseased tissues of the central nervous system could have enormous impact on the health and quality of life of large numbers of individuals by restoring lost function, or by treating or controlling disease states. Such probes have been fabricated at a high level of engineering sophistication. Unfortunately, when inserted into the brain a tissue reaction is initiated forming a scar that surrounds and electrically isolates the probe within a few weeks. This reaction is thought to primarily involve glial cells, and is undoubtedly dominated by the bulk surface of the probes which have a silicon oxide layer on top of single crystal silicon.
Model probes (Fig. 1) were microfabricated by photolithography with a 1×1mm tab used for gripping and inserting probes.