Functionalization Ti3C2Tx as highly sensitive and selective SERS substrate by reduction rapid synthesis strategy

In this study, we designed and prepared a novel, stable, and sensitive membrane-based surface-enhanced Raman scattering (SERS) substrate based on the synergistic interaction of two-dimensional MXene material Ti3C2Tx and silver nanoparticles (AgNPs). Using this AgNPs/Ti3C2Tx active substrate, a rapid SERS method for determination of paraquat residues in vegetables and fruits was developed. The AgNPs/Ti3C2Tx films were formed by dropping AgNO3 solution onto the film and drying, which was synthesized by wet chemical method, and then filtered into an exfoliated Ti3C2Tx film. The Ti3C2Tx film can not only effectively enrich analytes, but also provide charge transfer resonance enhancement. The homogeneous AgNPs particle size of 40-120 nm on the substrate surface of Ti3C2Tx can effectively enhance the Raman signal intensity, and the enhancement factor of methylene blue can reach 105. The detection limit of the detection method for paraquat in 9 fruit and vegetable matrices was lower than 3.0 μg/Kg, and the limit of quantification was lower than 12 μg/Kg. The results suggest that AgNPs/Ti3C2Tx platform could be used as a sensitive and reliable for food safety analysis based on SERS method.