Empirical structural design of core@shell Au@Ag nanoparticles for SERS applications

Surface-enhanced Raman scattering spectroscopy using bifunctional Au@Pt core–shell nanostructures can monitor the catalytic reaction dynamics in real time.

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Development of Effectual Substrates for SERS by Nanostructures-on flexible surfaces

Journal of Physics Conference Series ◽

10.1088/1742-6596/2114/1/012084 ◽

2021 ◽

Vol 2114 (1) ◽

pp. 012084

Author(s):

Hammad R. Humud ◽

Fatimah Jumaah Moaen

Keyword(s):

Raman Scattering ◽

Ag Nanoparticles ◽

Surface Enhanced Raman Scattering ◽

Wave Number ◽

Plasmonic Nanostructures ◽

Sers Substrate ◽

Two Dimensional ◽

Surface Enhanced ◽

Surface Enhanced Raman ◽

Enhanced Raman Scattering

Abstract The current study examines recent advancements in surface-enhanced Raman scattering (SERS), a technique that employs flexible surfaces as an active substrate, this surfaces consist from two-dimensional thermo-plasmonic grating. With 53 nm Au layer (was deposited on the 2D grating structure of the PDMS by the PVD method). The explosive wire technique was used to preparing Ag nanoparticles that were used for the purpose of SERS. The effect of the plasmonic nanostructures on the absorption spectra and Surface - Enhanced Raman Scattering (SERS) activities was examined. Rhodamine 6G dye was used as a probe molecule. X-Ray diffraction (XRD) was used to examine the structural characteristics of the nanoparticles. The morphology was assessed using Field Emission Scanning Electron Microscopy(FESEM). A twin beam UV-Vis Spectrophotometer was used to measure the absorption of the combined Rh6G dye (concentration 1×10“–6M) with the nanostructures. a Sunshine Raman microscope system and a 50mm objective lens, used for investigating the Raman spectra of the Rh6G combined with nanostructures. The results showed that the enhancement factor (EF) for SERS of R6G (1×M) reached to (2.2×10 3) When using Ag nanoparticles and (0.08 × 103) when R6G deposited directly on the flexible substrates without nanostructures at the wave number (1650 cm−1), we produced a recyclable, homogeneous, and highly sensitive SERS substrate with dependable reproducibility. For the SERS substrate, a surface made up of two-dimensional (2D) flexible grating substrates was chosen to provide multiple modalities in electrical and medicinal applications.

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Performance Improving Method of Aligned Silver Nanorod by Grafting Au@Ag Core–Shell Nanoparticles for Surface-Enhanced Raman Scattering

NANO ◽

10.1142/s1793292017501314 ◽

2017 ◽

Vol 12 (11) ◽

pp. 1750131 ◽

Cited By ~ 10

Author(s):

Jian Chen ◽

Peitao Dong ◽

Chaoguang Wang ◽

Chenyu Zhang ◽

Junfeng Wang ◽

...

Keyword(s):

Raman Scattering ◽

Surface Enhanced Raman Scattering ◽

Core Shell ◽

Sers Substrate ◽

Shell Nanoparticles ◽

Simple Method ◽

Surface Enhanced ◽

Surface Enhanced Raman ◽

Enhanced Raman Scattering ◽

Core Shell Nanoparticles

A simple method for improving surface-enhanced Raman scattering (SERS) performance of aligned silver nanorod (Ag NR) array was investigated. This method was to construct a kind of hybrid substrate by grafting Au@Ag core–shell nanoparticles (NPs) into Ag NR array using poly(2-vinylphridine) (P2VPy) as a bridging agent. The hybrid substrate yielded excellent SERS performance as its detection limit improved from 10[Formula: see text] M to 10[Formula: see text] M using trans-1,2-bis(4-pyridyl)ethylene (BPE) as probe molecule, which was increased by two orders of magnitude compared with Ag NR array substrate. The significant improvement of SERS performance of Ag NR arrays was attributed to the addition of Au@Ag core–shell NPs. As a result of surface plasmon resonance generated by the interaction of electromagnetic (EM) (IAEM) filed between NP and NR structures, increasing hotspots were found at the connections of NPs and NRs, the gaps of adjacent rods, and the gaps of two particles consequently. These results were validated by the finite difference time domain (FDTD) calculation. Besides, hybrid substrate shows good performance in stability and reproducibility. The proposed method was simple and robust, which promoted SERS performance of Ag NR array effectively, showing great potential in the application of SERS substrate fabrication and SERS-based bio-chemical sensing.

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Fabrication and Characterization of a Highly-Sensitive Surface-Enhanced Raman Scattering Nanosensor for Detecting Glucose in Urine

Nanomaterials ◽

10.3390/nano8080629 ◽

2018 ◽

Vol 8 (8) ◽

pp. 629 ◽

Cited By ~ 6

Author(s):

Yudong Lu ◽

Ting Zhou ◽

Ruiyun You ◽

Yang Wu ◽

Huiying Shen ◽

...

Keyword(s):

Raman Scattering ◽

Internal Standard ◽

Surface Enhanced Raman Scattering ◽

Quantitative Detection ◽

Core Shell ◽

Ag Nps ◽

Vis Spectroscopy ◽

Surface Enhanced ◽

Surface Enhanced Raman ◽

Enhanced Raman Scattering

Herein we utilized coordination interactions to prepare a novel core-shell plasmonic nanosensor for the detection of glucose. Specifically, Au nanoparticles (NPs) were strongly linked with Ag+ ions to form a sacrificial Ag shell by using 4-aminothiophenol (4-PATP) as a mediator, which served as an internal standard to decrease the influence of the surrounding on the detection. The resultant Au-PATP-Ag core-shell systems were characterized by UV-vis spectroscopy, transmission electron microscopy, and surface-enhanced Raman scattering (SERS) techniques. Experiments performed with R6G (rhodamine 6G) and CV (crystal violet) as Raman reporters demonstrated that the Au@Ag nanostructure amplified SERS signals obviously. Subsequently, the Au@Ag NPs were decorated with 4-mercaptophenylboronic acid (4-MPBA) to specifically recognize glucose by esterification, and a detection limit as low as 10−4 M was achieved. Notably, an enhanced linearity for the quantitative detection of glucose (R2 = 0.995) was obtained after the normalization of the spectral peaks using 4-PATP as the internal standard. Finally, the practical applicability of the developed sensing platform was demonstrated by the detection of glucose in urine with acceptable specificity.

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