Fe3O4-Ag nanohybrids as novel SEIRA and SERS substrate for thymine detection

Hybrid nanostructures Fe3O4-Ag, combining magnetic and plasmonic properties based on nanomagnetite and Ag nanoparticles, were synthesized and characterized. Enhanced SEIRA and SERS signals of thymine adsorbed on these hybrid nanostructures were obtained. It has been shown that molecular groups of thymine are enhanced differently depending on the type of interaction and the orientation of the molecule relative to the surface. It is shown that the "chemisorption" of thymine on Fe3O4-Ag also contributes to the enhancement of the SEIRA and SERS signal. It is assumed that the coordination of thymine to Ag in Fe3O4-Ag occurs mainly through the deprotonated N1 of thymine, but partial coordination of thymine through N(3 )is also possible. According to the results of the study, the resulting Fe3O4-Ag nanohybrids have the properties of plasmonic metals, while retaining ferromagnetic properties, and have great potential as substrates for surface-enhanced vibration spectroscopy in trace analysis.