Surface Acoustic Wave Delay Line for Biosensor Application

This paper presents the analysis, design and manufacture of a Surface Acoustic Wave (SAW) delay line for use as a bond-rupture biosensor. In contrast to commercial devices used in signal processing, the analyte changes the delay path of the developed device coating it in a layer of particles. The energy of the surface acoustic waves then removes the particles. Design constraints arise from both the manufacturing process and intended application. The developed device is reusable, durable and able withstand cleaning. As the device is in the prototype stage it is of reasonable size. The developed device is designed to work within an existing electronics system developed for quartz crystal microbalance bond-rupture; this places restrictions on the operating frequency of the device and impedance. Using established impulse response models the SAW device is designed for this application. Experimental results are compared with the simulation predictions and future improvements are considered.