A Label-free Helicobacter pylori VacA Antibody Immunosensing Platform Based on Silver Nanoparticles Decorated Reduced Graphene Oxide/ionic Liquid Composites Electrode

A label-free Helicobacter pylori ( H. pylori ) VacA antibody immunosensing platform based on silver nanoparticles doped reduced graphene oxide/ionic liquid composites electrode (Ag@rGO/CILPE) was successfully prepared. Ag@rGO/IL nanocomposites not only enhanced the immobilization capacity for VacA antigen but also improved the response signal of the immunosensor, it could achieve selective recognition for VacA antibody. The linear range of VacA antibody was 0.01-1 ng mL -1 using the proposed method, with a detection limit of 5 pg mL -1 . The constructed immunosensor had good specificity, reproducibility, and stability. It could be used for the determination of VacA antibody in human serum samples, achieving the typing diagnosis of H. pylori infection.