Highly sensitive detection of clenbuterol using competitive surface-enhanced Raman scattering immunoassay

In this report, we present a novel approach to detect clenbuterol based on competitive surface-enhanced Raman scattering (SERS) immunoassay. Herein, a SERS nanoprobe that relies on gold nanoparticle (GNP) is labeled by 4,4′-dipyridyl (DP) and clenbuterol antibody, respectively. The detection of clenbuterol is carried out by competitive binding between free clenbuterol and clenbuterol-BSA fastened on the substrate with their antibody labeled on SERS nanoprobes. The present method allows us to detect clenbuterol over a much wider concentration range (0.1–100 pg mL−1) with a lower limit of detection (ca. 0.1 pg mL−1) than the conventional methods. Furthermore, by the use of this new competitive SERS immunoassay, the clenbuterol-BSA (antigen) is chosen to fasten on the substrate instead of the clenbuterol antibody, which could reduce the cost of the assay. Results demonstrate that the proposed method has the wide potential applications in food safety and agonist control.

Schemes of SERS nanoprobes preparation (a) and competitive SERS immunoassay for clenbuterol (b).Figure optionsDownload as PowerPoint slideHighlights
► A new method for clenbuterol detection by the use of a competitive SERS immunoassay has been developed.
► 4,4′-Dipyridyl is chosen as the Raman reporter due to its fast-labeled, nontoxic and bifunctional properties.
► The present method could detect clenbuterol over a wide dynamic concentration range and exhibit significant specificity in real samples.
► The technique is more sensitive and simpler than the conventional method ELISA.