[Research and development of a piezoelectric immunosensor for detecting Treponema pallidum]

We utilized polyethylenimine (PEI) and Glu solution to immobilize the antibody of Treponema Pallidum on the silver electrode of piezoelectric quartz crystal and detect the standard antigen solution at different concentration. The antibody keeps the intrinsic Y type molecular structure revealed by AFM. The resonant range of the sensor is between 5 x 10(-5) - 1.25 x 10(-4) g/mL and the correlation coefficient is 0.9976, the optimal resonance pH is 7.5. We found the sensor having good selectivity in comparison with the method using BSA. At last, a discussion on the reproducibility of the sensor is presented.