Silicon dioxide binding protein capable of directionally fixing antibody as well as preparation method and application of silicon dioxide binding protein

The invention discloses a silicon dioxide binding protein for directionally fixing an antibody as well as a preparation method and application thereof, the protein consists of a silicon dioxide binding tag (Si-tag) and a protein G structural domain (2C2) with two repetitive units, and has the functions of stably adhering to the surface of silicon dioxide and efficiently capturing the antibody. The recombinant protein structure can be irreversibly adsorbed on the surface of silicon dioxide through a simple incubation process, and the Fc terminal of a monoclonal antibody (mAbs) is captured, so that directional fixation of the antibody is realized. The invention provides a method basis for high-throughput immobilization of the antibody, meets the technical requirements of batch immobilization of antibodies of different pathogens/biomarkers on a biosensing platform on the surface of silicon dioxide, and can be used for multiple detection of pathogens/biomarkers in clinical samples. 本发明公开了一种定向固定抗体的二氧化硅结合蛋白及其制备方法和应