Fluorescence quenching properties of Au-Ag-Pt tri-metallic nanorod: The application in specific detection of alpha-fetoprotein

In this paper, the fluorescence quenching characteristics of Au-Ag-Pt core-shell nanorods have been studied. Due to nonradiative energy transformation, the fluorescence emission intensity of bovine serum albumin (BSA) could be greatly quenched. It has been found that the quenching effect of Au-Ag-Pt core-shell nanorods could be optimized by adjusting the concentration of chloroplatinic acid. Based on the fluorescence quenching properties of Au-Ag-Pt core-shell nanorods, Au-Ag-Pt trimetal fluorescence quenching nanoprobe has been prepared, and the specificity of alpha-fetoprotein (AFP) detection has also been realized. In order to guarantee the sensing specificity, the surface modification including carboxyl replacement, carboxyl activation and antibody connec-tion have been performed on Au-Ag-Pt core-shell nanorods. By using the principle of specific combination of antigen and antibody, the specific detection of AFP has been realized with a lower detection limit of 4.0 pg/mL, and the linear detection range spans a scope from 0.03 to 0.5 ng/mL. Interference experiments and the actual samples detection results show that the Au-Ag-Pt trimetal core-shell nanorod probes have good anti-interference and repeatability.