Nanoscaled interdigitated electrode arrays for biochemical sensors

Nanoscaled interdigitated electrode arrays were made with deep UV lithography. Electrode widths and spacings from 500 down to 250 nm were achieved on large active areas (0.5 x 1 mm). These electrodes allow for the detection of affinity binding of biomolecular structures (e.g. antigens, DNA) by impedimetric measurements. Such a sensor with Pd electrodes on SiO2 is developed and theoretically analysed. It was experimentally characterised in KCl solutions demonstrating its bulk-insensitive behaviour and the immobilisation of glucose oxidase (GOD) could be monitored by measuring the double layer impedance. (C) 1998 Elsevier Science S.A. All rights reserved