Fabrication of GO/Fe3O4@Au MNPs for Magnetically Enriched and Adsorptive SERS Detection of Bifenthrin

Abstract

The detection of bifenthrin is closely related to the adsorption of SERS substrates. In this study, superparamagnetic Fe3O4@Au MNPs coated with GO were used to detect the adsorption and enrichment of bifenthrin molecules with benzene rings. Firstly, the thermal solvent method synthesized Fe3O4 magnetic nanoparticles (MNPs) with a particle size of ~250 nm. Next, polyethylene imide (PEI) was used as an intermediate layer to modify the surface of Fe3O4 to form a positively charged ultra-thin polymer middle layer. Next, the gold shell was developed by adsorption of ~20 nm AuNPs, without affecting the magnetic properties. Then, the additional amount of colloidal gold and GO on SERS performance was systematically studied. Using crystal violet (CV) as the probe, we investigated the SERS performance of composite nanomaterials. The lowest detected concentration reached 10−8 mol/L, confirming that the composite functional material had good SERS activity and magnetic properties. Finally, the substrate was used to detect bifenthrin in an acetone solution, and the lowest detection concentration was 10−8 mol/L. These results showed that the prepared GO/Fe3O4@Au MNPs were efficient SERS substrates that could detect bifenthrin pesticide residue with high sensitivity.

Design, Fabrication, and Applications of SERS Substrates for Food Safety Detection: Review

“…The design of SERS substrates should be tailored to the specific target substances. In food safety applications, the target substances can be categorized into two groups: small amount molecules [ 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 ] and tiny biomaterials, such as cells [ 89 , 90 , 91 , 92 ], cell walls [ 93 , 94 , 95 , 96 ], and spores [ 97 , 98 , 99 , 100 ]. The key distinction between these two categories lies in their size.…”

“…The key distinction between these two categories lies in their size. Molecules are typically smaller than 100 nm and can be accommodated within the hotspot of the SERS substrate [ 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 ]. On the other hand, tiny biomaterials are generally larger than 100 nm and cannot fit into the small hotspot of the SERS substrate [ 89 , 90 , 91 , 92 , 93 , 94 , 95 , 96 , 97 , 98 , 99 , 100 ].…”

UIO-66/Ag/TiO2 Nanocomposites as Highly Active SERS Substrates for Quantitative Detection of Hexavalent Chromium

“…Surface-enhanced Raman scattering (SERS) technology has the advantages of high sensitivity, fast detection speed, non-destructive detection and no sample pretreatment [16], and it is often used to identify harmful substances including organic dyes, pesticides and heavy metal ions [17][18][19]. SERS detection of Cr can be divided into the indirect approach and the direct approach [20][21][22][23][24].…”