Polyvinyl Alcohol (PVA)/Nb2C/Ag Flexible Surface Enhanced Raman Spectroscopy (SERS) Substrate for Sensitive Determination of Phosmet Residues on Apple Surfaces

Polyvinyl alcohol (PVA)/Nb2C/Ag flexible SERS substrate was prepared by coating AgNPs in situ reduced by Nb2C on the surface of PVA. Sensitive SERS detection was achieved by adjusting the concentration of AgNO3, enabling the detection of 4-MBA with good homogeneity and reproducibility. The pesticide residues of phosmet on the surfaces of apples were detected by a simple wiping method with the flexible substrate. The detection range was 0.5 – 100 ppm, which met the detection standard of phosmet for fruits. The PVA/Nb2C/Ag flexible SERS substrate has the potential for convenient, rapid, and sensitive detection of pesticide residues on fruit surfaces.