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

Abstract

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 × 108, and the limit of detection (LOD) was 1 × 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.

Recent Development and Applications of Stretchable SERS Substrates

“…Interestingly, bioinspired SERS substrates have also been developed for high-performance sensing, in which natural biological materials such as taro leaves [81], reed leaves [49], and cicada wings [82,83] were used as the replication templates. Figure 4b illustrates the procedure of fabricating micro and nanostructured SERS sensors using a natural reed leaf as the template [49].…”

Preparation and investigation of high-performance flexible and transparent Ag/PDMS substrate with the bionic structure of cicada wings

“…Among them, the template method can costefficiently prepare 3D SERS substrates in a large area. In addition to the commonly used man-made templates such as anodized aluminum [15] and porous silicon [16], many researchers have used unique micro-nano structures in nature to prepare SERS substrates in a biomimetic way [17], such as diatom particles [18], lotus leaf surfaces [19], insect wings [20], etc. Natural nanostructures, especially those regular ones such as cicada wings, are economical and desirable SERS support materials.…”