| Summary: | The rapid and sensitive detection of <i>Staphylococcus aureus</i> (<i>S. aureus</i>) is essential to ensure food safety and protect humans from foodborne diseases. In this study, a sensitive and facile electrochemical immunosensor using AuPdPt trimetallic nanoparticles functionalized multi-walled carbon nanotubes (MWCNTs-AuPdPt) as the signal amplification platform was designed for the label-free detection of <i>S. aureus</i>. The nanocomposite of MWCNTs-AuPdPt was prepared by an in situ growth method of loading AuPdPt trimetallic nanoparticles on the surface of MWCNTs. The synthesized MWCNTs-AuPdPt featured good conductivity and superior catalytic performance for hydrogen peroxide. The nanocomposite of MWCNTs-AuPdPt with good biocompatibility and high specific surface area was further functionalized by anti-<i>S. aureus</i> antibodies. The immobilized antibodies could efficiently capture <i>S. aureus</i> to the modified electrode by an immune reaction, which resulted in the change of catalytic current intensity to realize the sensitive detection of <i>S. aureus</i>. The designed immunosensor could detect <i>S. aureus</i> in a linear range from 1.1 × 10<sup>2</sup> to 1.1 × 10<sup>7</sup> CFU mL<sup>−1</sup> with a low detection limit of 39 CFU mL<sup>−1</sup>. Additionally, the proposed immunosensor was successfully applied to determine <i>S. aureus</i> in actual samples with acceptable results. This strategy provided a promising platform for highly sensitive determination of <i>S. aureus</i> and other pathogens in food products.
|
|---|
