ADVANTAGES OF USING MICROFABRICATED EXTRACELLULAR ELECTRODES FOR IN-VITRO NEURONAL RECORDING

We describe fabrication methods and the characterisation and use of ex tracellular microelectrode arrays for the detection of action potentia ls from neurons in culture, The 100 mu m(2) platinised gold microelect rodes in the 64 electrode array detect the external current which flow s during an action potential with S:N ratios of up to 500:1, giving a maximum recorded signal of several millivolts, The performance of thes e electrodes is enhanced if good sealing of the cells over the electro des is obtained and further enhanced if the electrodes and the cells l ie in a deep groove in the substratum, The electrodes can be used for both recording and stimulation of activity in cultured neurons and for recording from multiple sites on a single cell, The use of such elect rodes to obtain recordings from invertebrate neurons is described, The particular advantages of these electrodes, their long term stability, non-invasive nature, high packing density, and utility in stimulation , are demonstrated. (C) 1995 Wiley-Liss, Inc.