A contactless surface acoustic wave biosensor

Surface acoustic wave sensors operating in liquid generally cause problems resulting from wire bonding. The authors present an approach for a biosenso r where the need for bonding wires is eliminated by utilizing inductive cou pling of the sensor device to the RF circuitry. Protection of the electrode s from the liquid is achieved by coating the device surface with a SiO2 lay er, resulting in a simplified handling of the devices. The first measuremen ts with a sensor operating at 420 MHz are presented, demonstrating the pote ntial of this operating principle for biosensing. (C) 1999 Elsevier Science S.A. All rights reserved.