Antigen-labeled mesoporous silica-coated Au-core Pt-shell nanostructure: a novel nanoprobe for highly efficient virus diagnosis

BACKGROUND: As an emerging research area of artificial enzymes, nanozyme, the catalytic nanomaterials with enzyme-like characteristics, have attracted enormous attention in research. Here, a nanozyme probe has been realized by utilizing antigen-labeled mesoporous silica-encapsulated Au-core Pt-shell (Au@Pt@SiO(2)) nanostructures for the diagnosis of rubella virus (RV). Pt nanoparticles have been suggested to act as potent peroxidase mimetics with high activities. However, smaller Pt nanoparticles are very easily aggregated, which has negative effects on the catalytic activities. RESULTS: In this work, the use of gold nanorod as the support favours the well dispersion of the small Pt nanoparticles to improve the stability of them. Furthermore, the designed the silica shell could also isolate the recognition antigens from the surface reactive sites, retaining catalytic activity of the inner nanozyme. In addition, compared with antigen-labeled horseradish peroxidase (HRP), the antigen-labeled Au@Pt@SiO(2) nanozyme was more stable and robust. A capture enzyme-linked immunosorbent assay (ELISA) for the determination of RV showed that the antigen-labeled Au@Pt@SiO(2) nanozyme-based ELISA exhibited good sensitivity. CONCLUSIONS: The highly sensitive peroxidase-like activity of antigen-labeled Au@Pt@SiO(2) nanozyme, along with their catalytic stability and robustness, can facilitate their utilization in biochemical assays and clinical diagnosis.