FIELD-EFFECT TRANSISTOR ARRAY FOR MONITORING ELECTRICAL-ACTIVITY FROMMAMMALIAN NEURONS IN CULTURE

A field-effect transistor (FET) array has been fabricated and used for recording of electrical signals from neural cells. The array consists of p-channel FETs with non-metallized gates. The size of the gates of the 16 FETs are from 28 x 12 mu m(2) down to 10 x 4 mu m(2) and are a rranged in a 4 x 4 matrix on 200 mu m centers. For the device fabricat ion process we have especially focused on high sensitivity, good long- term stability in physiological conditions, and sufficient reduced sig nal-to-noise ratio. Special care was taken on the encapsulation techni que of the device to allow surface modification based on the self-asse mbly technique. It can be shown that the microelectronic device surfac e can be modified with a synthetic peptide linked to the surface. Tail oring of the surface composition using this method allows hippocampal neurons to adhere and grow for days. More importantly, these cells dev elop typical electrical characteristics when cultured on this artifici al surface. Using this approach neuron-FET couplings were recorded. (C ) 1997 Elsevier Science Limited.