The present invention provides a hexagonal, delay line surface acoustic wave device fabricated on a a piezoelectric substrate, such as lithium tantalate, coated with an insulating waveguide on to which a sensing film, such as an anti-human Interleukin-6 biosensor film, is physically absorbed. The acoustic waves that propagate along the delay lines of the SAW device provide for detection of biological species along one delay line and simultaneously provide for removal of non-specifically bound protein along the remaining delay lines.