SAW based mass-loading biosensor for DNA detection

In this paper, a Surface Acoustic Wave (SAW) biosensor with gold coated delay area detecting DNA sequences is proposed. By well-designed procedures of device structure and parameters, we manufactured a simple and high-performance SAW on LiNbO ₃ substrate. The SAW biosensor with gold delay area that is connected to PCB board through bonding wires could be used for the direct measurement and sonic path comparative measurement of S ₁₁ parameter by using Network Analyzer. The device works near 65MHz. The loading mass of DNA probe and target DNA sequences are obtained from frequency shift, which is big enough in this work due to an effective biological treatment method. The testing result shows that the SAW sensor has a high sensitivity of 1.2pg/ml/Hz.