A new SERS quantitative analysis method for trace malathion with recognition and catalytic amplification difunctional MOFTb@Au@MIP nanoprobe

New multifunctional nanomaterial preparation and its application to trace pollutant analysis are interesting to peoples. Using terbium metal-organic framework loaded gold nanoparticles (MOFTb@Au) as the nanosubstrate and 3-aminopropyltriethoxysilane (APTES) as the functional monomer, a new bifunctional nanosurface molecularly imprinted polymer nanoprobe of MOFTb@Au@MIP with strongly recognition and catalytic amplification functions was prepared by the microwave sol-gel procedure. It was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier infrared spectroscopy (FTIR) and other techniques. The nanoprobe was found to specifically recognize malathion (MAL) and catalyze the L-cysteine (Cys)-HAuCl4 nanogold indicator reaction to amplify the molecular spectral signal. The gold nanoparticles (AuNPs) generated in the system show a strong surface-enhanced Raman scattering (SERS) effect, resonant Rayleigh scattering (RRS) peak and UV absorption (Abs) peak at 1615 cm-1, 370 nm and 520 nm, respectively. Based on this, a new SERS/RRS/Abs trimode method for the detection of MAL can be established. It has been applied to the analysis of cereal samples with satisfactory recoveries of 95.2-107.4% and precision of 3.76-9.06%.