Abstract: Ag-CDs nanoparticles with core-shell structure were obtained by reducing Ag ion with carbon dots (CDs). The results show that the diameter of Ag core is about 30 nm, and the thickness of surface carbon film is about 2.2 nm. Ag-CDs nanoparticles have excellent peroxidase-like activity and surface enhanced Raman scattering (SERS) activity, which can catalyze the oxidation of 3,3′,5,5′-teramethylbenzidine (TMB). Because uric acid can reduce the oxidized TMB, the concentration of uric acid can be detected by colorimetry. Taking Ag-CDs nanoparticles as the SERS substrate, and the concentration of uric acid can be detected by SERS spectrum. The collaborative detection of the two methods can greatly improve the reliability of the detection.

Key words: peroxidase-like enzyme, core-shell structure nanoparticle; , uric acid, surface enhanced Raman scattering