Optimization of surface enhanced Raman scattering performance based on Ag nanoparticle-modified vanadium-titanium nanorods with tunable nanogaps

The combination of new noble metal nanomaterials and surface enhanced Raman scattering (SERS) technology has become a new strategy to solve the problem of low sensitivity in the detection of traditional Chinese medicine. In this work, taking natural cicada wing (C.w.) as a template, by optimizing the magnetron sputtering experimental parameters for the growth of Ag nanoparticles (NPs) on vanadium-titanium (V-Ti) nanorods, the nanogaps between the nanorods were effectively regulated and the Raman signal intensity of the Ag15/V-Ti20/C.w. substrate was improved. The proposed homogeneous nanostructure exhibited high SERS activity through the synergistic effect of the electromagnetic enhancement mechanism at the nanogaps between the Ag NPs modified V-Ti nanorods. The analytical enhancement factor (AEF) value was as high as 1.819 x 108, and the limit of detection (LOD) was 1 x 10-11 M for R6G. The large-scale distribution of regular electromagnetic enhancement hot spots ensured the good reproducibility with the relative standard deviation (RSD) value less than 7.31%. More importantly, the active compound of Artemisinin corresponded the pharmacological effect of Artemisia annua was screened out by SERS technology, and achieved a LOD of 0.01 mg/l. This reliable preparation technology was practically applicable to produce SERS-active substrates in detection of pharmacodynamic substance in traditional Chinese medicine.(c) 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement

Automated summary

The combination of new noble metal nanomaterials and surface enhanced Raman scattering (SERS) technology is a promising strategy to overcome the low sensitivity in the detection of traditional Chinese medicine. In this study, Ag nanoparticles (NPs) were grown on vanadium-titanium (V-Ti) nanorods using natural cicada wing as a template, and the nanogaps between the nanorods were effectively regulated to improve the Raman signal intensity. The proposed homogeneous nanostructure exhibited high SERS activity through the synergistic effect of the electromagnetic enhancement mechanism. The technology also allowed for the screening of active compounds in traditional Chinese medicine.