Application of a Lateral Field Excited Acoustic Wave Device as a New Sensor Principle in Biointerface Analysis

AT-cut quartz crystals have been excited by applying a lateral electric field in the plane of the disk. Deposition of self-assembled monolayers proves the expected sensitivity of the sensor to small mass changes. When subjected to a liquid acoustic load the sensor exhibits an extremely high sensitivity to permittivity and conductivity of the liquid. In combination with an additional artificial interface layer, the influence on the resonance will be discussed in terms of reorganization of the electric field distribution within the quartz. Due to the mechanical and electrical nature of medium-sensor-interaction, access to interfacial properties is anticipated.