查看文章

We designed and fabricated the nanomechanical Pb(Zr_0.52Ti_0.48)O₃ (PZT) cantilever; we demonstrated a novel electrical measurement, under a controlled ambient temperature and humidity, for label-free detection of a prostate-specific antigen (PSA); and we achieved a detection sensitivity as low as 10pg/ml. For the fabrication of our nanomechanical PZT cantilevers, we used composite layers of Ta/Pt/PZT/Pt/SiO₂ on a SiN_x supporting layer for electrical self-sensing without external oscillators. This method allows PSA proteins to be detected via a simple electrical measurement of the resonant frequency change generated by the molecular interaction of the antigen (Ag) and the antibody (Ab). The resonant frequency shifted due to the specific binding of the PSA Ag to its Ab which is immobilized via calixcrown self-assembled monolayers on an Au surface deposited on a nanomechanical PZT cantilever. We …