Development of a novel protein biochip enabling validation of immunological assays and detection of serum IgG and IgM antibodies against Treponema pallidum pathogens in the patients with syphilis

Abstract In this study, we developed a novel protein biochip methodology that was characterized by dithiobis (succinimidyl undecanoate) (DSU) and specialized for detection of serum IgG and IgM antibodies against Treponema pallidum pathogens in the patients with syphilis, respectively. The biochips were validated by a dimension of atomic force microscope (AFM). The visualized detection limit of IgG antibody on the biochip was 0.39 μg/ml. Finally, 286 serum samples from the patients with syphilis were simultaneously tested on the rTpN15–17–47 coated biochips. The results were evaluated in comparison with the assays of T. pallidum particle agglutination (TPPA) and the toluidine red unheated serum test (TRUST). The result demonstrated that the relative positive rate in the 286 patients by biochip was 99.0%, similar to that by TPPA (97.9%, P >0.05) and higher than that by TRUST, (76.2%, P T. pallidum on a larger scale, but also for monitoring therapy modality of the disease.