Capacitive measurements in electrolyte-insulator-semiconductor (EIS) systems modified by biological materials

Abstract The modification induced by the superimposition of biological materials upon the insulating layer of an EIS system are analysed. The insulating layer utilised is Si3N4. Capacitance—voltage (C—V) curves are measured for the EIS system and compared to those obtained after coating the insulating layer with laminin, a compound that is routinely utilized in biological research for improving cell adhesion to substrates and also fro cell guidance. Our data show that the pH response of the EIS system is preserved after the addition of laminin, even if the sensitivity of the device is reduced. Images of unstained living mouse neuroblastoma cells adhering to laminin-treated Si3N4 substrates are obtained by means of the non-destructive technique of high-resolution scanning reflection acoustic microscopy. Details of the cell morphology demonstrate the healthy and differentiated state of the cells. On the whole, our data suggest the feasibility of coupling living neuronal cells to pre-treated microelectronic devices.