Plasmonic structure with nanocavity cavities for SERS detection of pesticide thiram
Yongjun Zhang, Aonan Zhu, Yaxin Wang, Xiaolong Zhang
Abstract
Abstract Excessive thiram residues in food have the potential to negatively impact human health. Hence, the development of a convenient and fast detection method is highly desirable. In this study, an efficient, repeatable, and sensitive surface-enhanced Raman scattering (SERS) active chip was manufactured via a low-cost colloidal lithography technique. The plasmonic structure was composed of a series of silver nanospheres and nanowires. Interestingly, this type structure creates a nanocavity space with a characteristic geometry generating a strong electromagnetic field coupling. The finite-different time-domain software was employed to simulate the electromagnetic field distribute on the nanocavity. Accordingly, SERS active chip that displays ultra-low concentration detection of thiram (10 −11 M) was realized. Moreover, the excellent reproducibility of thiram (10 −6 M) practical detection on an apple pericarp has great potential for application in food safety.