Biocompatibility of silicon nanowires: A step towards IC detectors

Recording bioelectric signals at high spatio-temporal resolution with low invasiveness is a major challenge in the field of bio-nanotechnology. Insofar, bioactive signals have been recorded with improved signal-to-noise ratio from cells in culture using arrays of nanopillars. However, production of such nanoscale electrodes is both time-consuming, pricey and might be only scarcely compatible with the Complementary Metal-Oxide-Semiconductor integrated circuits (CMOS-IC) technology. To take a step forward, we introduced an innovative approach to fabricate small, high-density Silicon NanoWires (SiNWs) with a fast, relatively inexpensive and low-temperature (200 °C) method. Growth of such SiNWs is compatible with ICs, thus theoretically allowing on-site amplification of bioelectric signals from living cells in tight contact. Here, we report our preliminary results showing biocompatibility and neutrality of SiNWs used as seeding substrate for cells in culture. With this technology, we aim to produce a compact device allowing on-site, synched and high signal/noise recordings of a large amounts of biological signals from networks of excitable cells (e.g. neurons) or from different areas of a single cell surface, thus providing super-resolved descriptions of bioelectric waveforms at the microdomain level