Multisensor silicon needle for cardiac applications

An integrated chemical sensor with multiple ion and temperature sensors, composed of two ISFETs (pH and K/sup +/), one platinum pseudo-reference electrode and temperature sensor based on a platinum resistor has been realised by using a CMOS-compatible technology and silicon micromachining. This paper describes a summary of the fabrication process and results of the device characterisation in vitro. The feasibility of the fabrication technology has been demonstrated and all devices have operated satisfactory, with a response showing good sensitivity and linearity. This multisensor will be used in the on-line early detection of myocardial ischemia during cardiac surgery while the heart is artificially arrested (extracorporeal circulation).