MICROFABRICATION TECHNOLOGY OF FLEXIBLE MEMBRANE-BASED SENSORS FOR IN-VIVO APPLICATIONS

Potentiometric ion-sensitive planar microelectrode arrays, and amperom etric enzyme-containing biosensors were fabricated by photolithographi c microelectronic technology on a flexible polyimide substrate. The st eps of the microelectronics processing are summarized in more detail t han previously described. The ion-selective electrodes were tested in blood serum, whole blood, and in the hamstring muscle of anesthetized rabbits. The test and performance characteristics of planar pH are emp hasized, and K+, Na+, and Ca2+ data are included in this review. New a pplied results are presented from experiments where the electrodes hav e been implanted into an in situ porcine beating heart at the midmyoca rdial depth in order to monitor H+ and K+ changes during the course of coronary artery occlusion.