A novel immobilization method for piezoelectric immunosensor with high sensitivity and good stability

The immobilization of cancer antigens onto the surface of piezoelectric immunosensor by a novel method was presented and evaluated for its potential use in early cancer detection. A 3rd overtone 10MHz AT-cut quartz crystal resonator was applied to detect the antibody of NuTu-19 ovarian cancer cell in serum samples using this novel immobilization method. The NuTu-19 ovarian cancer cells were planted on the electrode surface, the resulting very small mass change is then transformed into the change in frequency of crystal resonator. A self-made frequency counter was employed to display the frequency change. The change in resonance frequency was from 108 to 282Hz. The antibody content of NuTu-19 detected in immunized serum samples was 341ng/ul, and only 8% deviation compare to the data obtained from the protein quantification method. This immobilization method gave good results in terms of sensitivity, reproducibility and stability.