Shear-horizontal surface acoustic wave biosensors for POCT

An immunoassay-based biosensor using shear horizontal surface acoustic wave (SH-SAW) devices for point-of-care-testing (POCT) applications is described. The SH-SAW biosensor is composed of a disposable SH-SAW biosensor chip and an electrical reader connected to the biosensor chip. The biosensor chip is a quartz-based 250 MHz SH-SAW delay-line which has a gold surface covered with antibodies. A palm-sized electric reader connected to a smart-phone for detecting antigen-antibody reactions has been demonstrated. In this paper, a unique air-cavity structure and a reflection type delay-line design for the SH-SAW biosensor chip are described. The SH-SAW biosensor must be a strong candidate for future home healthcare applications.