Rapid determination of thiram in lake water using Au/Fe3O4 nanoparticles decorated MOF-867 as efficient surface-enhanced Raman scattering substrate

Rapid determination of pesticide residues in water is of vital importance for human health. However, rapid, reliable, and highly sensitive detection of pesticide residues in water environments remains a challenging issue. In this paper, we prepare Fe3O4/MOF-867 composites using the hot solvent method, and Au+ is reduced to Au NPs by the reducing agent and attached to the film of Fe3O4/MOF-867 composites by the addition of APTES as a linker to synthesize the Au/Fe3O4/MOF-867 SERS substrates. Then, we change the Fe3O4 content and the concentration of the reducing agent to obtain the optimal substrate. The substrate has a detection capability of up to 10-9 M for probe molecule R6G and the RSD is less than 5%, which demonstrates that the substrate has excellent SERS effect and reproducibility. In addition, the Au/Fe3O4/MOF-867 SERS substrates have been applied for the determination of thiram in lake water samples, with its limit of detection (LOD) up to 3.8 × 10-10 M. The Au/Fe3O4/MOF-867 SERS substrates can quickly and efficiently collect target analytes by magnetic enrichment, have high SERS performance, and have great potential for the rapid and sensitive detection of pesticide residues and other pollutants in the environment.