Rapid Determination of Thiram Residues in Fruit Juice by surface-enhanced Raman Scattering Coupled with a Gold@Silver nanoparticle-graphene Oxide Composite

摘要

With the large-scale use of pesticides, food safety issues caused by their residues have been drawn increasing concern. In this study, surface- enhanced Raman spectroscopy (SERS) coupled with a Au@Ag nanoparticle (NP)-graphene oxide (GO) composite substrate which was synthesized by a simple self-assembly method was applied for the rapid determination of thiram residues in fruit juice. To obtain high SERS activity, the loading and the aggregation of Au@Ag NP on the graphene oxide sheets were adjusted by controlling the size of Au@Ag nanoparticle and the concentration of graphene oxide in solution. Using the optimal conditions, the limit of detection for thiram standard solution was 6.3 ng/mL, while the limits of detection for thiram in apple juice and grape juice without any pretreatment were 36.7 and 134.4 ng/mL, respectively. The entire analytical process required less than 20min. The results indicated that SERS technology coupled with Au@Ag nanoparticle graphene oxide composite substrate was a simple, rapid, and sensitive approach for the determination of pesticide residues in fruit juice.