The rationality of using core–shell nanoparticles with embedded internal standards for SERS quantitative analysis based glycerol-assisted 3D hotspots platform

Abstract

3D hotspots matrix SERS platform in water with the assistance of 2.5% v/v glycerol has been constructed and then used in investigating the rationality of using core–shell nanoparticles with embedded internal standards for SERS quantitative analysis.

Applications of surface‐enhanced Raman spectroscopy in environmental detection

“…It was noted that this substrate was a good candidate to mitigate the effects of Raman signal fluctuation through the use of the embedded IS with a glycerol-assisted three-dimensional hot spot platform, and it has great promise for the accurate quantitative detection of various environmental pollutants. 70 Bacteria were recently used in conjunction with Au@Ag core-shell nanoparticles that were synthesized on the bacterium (Shewanella oneidensis). The bacteria's cell membrane worked as an IS when the Raman signals of both the target molecule and the bacteria were measured, and they maintained a relatively stable ratio for SERS intensity.…”

“…While the toxicity of most fungicides is generally low, prolonged exposure to these compounds may lead to adverse health effects such as neurological disruptions 126 . Several recent studies have utilized SERS to detect various fungicides, including tetramethylthiuram disulfide (THR), 39,53,61,70,79,127–161 carbendazim, 162–165 chlorothalonil, 166,167 MG, 168–173 TBZ (a fungicide and parasiticide) 20,79,153,155,173–178 and ferbam 20,178,179 . Among them, THR is the most studied due to its wide agricultural applications and strong binding with SERS nanosubstrates through the thiol group.…”

“…70,[75][76][77][78] A recent study focusing on the detection of the fungicides THR and TBZ utilized 4-MBA as an IS molecule. 4-MBA functionalized AuNPs acted as the core in an AgNP-coated shell, and the core-molecule-shell NPs self-assembled to form a dense nanoparticle array (Au@4-MBA@Ag NPs).…”

Self-Calibration 3D Hybrid SERS Substrate and Its Application in Quantitative Analysis

“…26 To overcome the competitive adsorption issue, the IS has been successfully embedded into the gap between the Au core and the Ag shell of a nanoparticle through controllable chemical synthesis. 31,32 Although buried IS does not compete with the target molecules for the exterior hot spot sites, the Ag shell also isolates the IS from the exterior hot spots, resulting in an inability to sense the variations in exterior hot spots. 33 Therefore, the Au core−IS−Ag shell nanoparticles can calibrate the variation of instrumental factors and the changes in the nanoparticle concentration in focal illumination volume, but cannot calibrate the changes in the hot spots.…”

MoS2/Au/Ag Nanostructures for Ratiometric Surface-Enhanced Raman Scattering Determination of Pesticide Residues

“…These unique advantages make SERS widely used in various fields including biomedicine, surface science, and trace analysis. − Many SERS-active nanocomposites have been constructed to achieve high-sensitivity and reproducible SERS detection. − Particularly, the SERS-active core–molecule–shell nanoparticles have exhibited great potential for an ideal quantitative SERS substrate combined with the ratiometric analysis. , By using the above strategy, (1) the internal standard (IS) molecules layer lies within the shell of noble metals so that it will not be influenced by the surrounding microenvironment; (2) the ratiometric method is employed to calibrate the variances caused by measuring conditions and instrument factors; and (3) the use of Au NPs as the core in core–molecule–shell nanoparticles can achieve a highly stable and uniform structure, while the shell of Ag NPs will generate largely enhanced Raman signals . Many researchers applied the core–Raman molecule–shell SERS system when fabricating the SERS-active materials, e.g., Au@4-MPy@Ag NPs, Au@gap@AgAu NPs, and Au–Mpy–Au–MnO 2 , which demonstrated higher reproducibility and more remarkable SERS quantitative capability than the single-signal strategy. − Based on the above, the SERS-active core–molecule–shell metal nanoparticles have extended the practical applications of the SERS technique for accurate analysis of pesticide residues.…”