A piezoelectric immunosensor based on micromachined monolithic film bulk acoustic resonator

Here we develop a novel immunosensor based on film bulk acoustic resonator (FBAR) to detect the biomarker of liver cancer. The alpha-fetoprotein (AFP), which is widely regarded as a serological marker for liver cancer in clinical diagnosis, is chosen as the target of the FBAR immunosensors. The surface of the FBAR was immobilized with monoclonal anti-AFP antibody as the specific bioprobe. The experimental results shows that the limit detectable AFP concentration of our proposed immunosensors is as low as 1 ng/ml, which is far less than that of quartz crystal microbalanc and comparable to that of enzyme-linked immunosorbent assay. Due to the compatibility of the fabrication of FBAR with CMOS process it can be mass produced, arrayed for analysis of multiple biochemical analyses simultaneously and integrated into a biochip, so that our proposed FBAR immunosensors can potentially be used for rapid multiple cancers diagnosis with low cost.