Browse
Submit Data
Databases
API
Help

Dataset Information

37 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Spontaneous versus Stimulated Surface-Enhanced Raman Scattering of Liquid Water.

ABSTRACT: We have observed for the first time the surface-enhanced (SE) signal of water in an aqueous dispersion of silver nanoparticles in spontaneous (SERS) and femtosecond stimulated Raman (SE-FSRS) processes with different wavelengths of the Raman pump (515, 715, and 755 nm). By estimating the fraction of water molecules that interact with the metal surface, we have calculated enhancement factors (EF): 4.8 × 10⁶ for SERS and (3.6-3.7) × 10⁶ for SE-FSRS. Furthermore, we have tested the role of simultaneous plasmon resonance and Raman resonance conditions for the a? ₁ + b?₃ overtone mode of water (755 nm) in SE-FSRS signal amplification. When the wavelength of the Raman pump is within the plasmon resonance of the metal nanoparticles, the Raman resonance has a negligible effect on the EF. However, the Raman resonance with the a? ₁ + b?₃ mode strongly enhances the signal of the fundamental OH stretching mode of water.

SUBMITTER: Filipczak P

PROVIDER: S-EPMC7874264 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Plasmonic and Electrostatic Interactions Enable Uniformly Enhanced Liquid Bacterial Surface-Enhanced Raman Scattering (SERS).

Project description:Surface-enhanced Raman spectroscopy (SERS) is a promising cellular identification and drug susceptibility testing platform, provided it can be performed in a controlled liquid environment that maintains cell viability. We investigate bacterial liquid-SERS, studying plasmonic and electrostatic interactions between gold nanorods and bacteria that enable uniformly enhanced SERS. We synthesize five nanorod sizes with longitudinal plasmon resonances ranging from 670 to 860 nm and characterize SERS signatures of Gram-negative Escherichia coli and Serratia marcescens and Gram-positive Staphylococcus aureus and Staphylococcus epidermidis bacteria in water. Varying the concentration of bacteria and nanorods, we achieve large-area SERS enhancement that is independent of nanorod resonance and bacteria type; however, bacteria with higher surface charge density exhibit significantly higher SERS signal. Using cryo-electron microscopy and zeta potential measurements, we show that the higher signal results from attraction between positively charged nanorods and negatively charged bacteria. Our robust liquid-SERS measurements provide a foundation for bacterial identification and drug testing in biological fluids.

| S-EPMC7564787 | biostudies-literature

Surface-enhanced Raman scattering of water in aqueous dispersions of silver nanoparticles.

Project description:The resonance Raman effect (RRE) is a phenomenon which results in a strong selective enhancement of Raman signals from the samples. Previous studies showed that the RRE in liquid water directly corresponds to its supramolecular structure. It was also reported that the electric-field-induced orientation of water molecules on the electrode surface results in the surface-enhanced Raman scattering (SERS) effect. In this work, we show the SERS effect for water molecules in the dispersion of silver nanoparticles (AgNPs) without any external electrical field. An enhancement factor was estimated to be (4.8 ± 0.8) × 106 for an excitation wavelength of 514.5 nm and for AgNPs with an average size of 34 ± 14 nm. The temperature experiment results showed a higher enhancement with temperature increase. Performed simulation studies revealed a slowdown of the mobility of the water molecules close to the surface of AgNPs.

| S-EPMC8182675 | biostudies-literature

Surface-Enhanced Raman Scattering-Active Substrate Prepared with New Plasmon-Activated Water.

Project description:Conventionally, reactions in aqueous solutions are prepared using deionized (DI) water, the properties of which are related to inert "bulk water" comprising a tetrahedral hydrogen-bonded network. In this work, we demonstrate the distinguished benefits of using in situ plasmon-activated water (PAW) with reduced hydrogen bonds instead of DI water in electrochemical reactions, which generally are governed by diffusion and kinetic controls. Compared with DI water-based systems, the diffusion coefficient and the electron-transfer rate constant of K3Fe(CN)6 in PAW in situ can be increased by ca. 35 and 15%, respectively. These advantages are responsible for the improved performance of surface-enhanced Raman scattering (SERS). On the basis of PAW in situ, the SERS enhancement of twofold higher intensity of rhodamine 6G and the corresponding low relative standard deviation of 5%, which is comparable to and even better than those based on complicated processes shown in the literature, are encouraging.

| S-EPMC6641932 | biostudies-literature

Detection of melamine in feed using liquid-liquid extraction treatment combined with surface-enhanced Raman scattering spectroscopy.

Project description:A rapid, selective, and sensitive method to determine the melamine content in animal feeds was developed using surface-enhanced Raman scattering spectroscopy on aggregated 55 nm Au nanoparticles with liquid-liquid extraction sample preparation. Butyl alcohol was used as the initial extraction solvent, and liquid-liquid extraction was performed twice using HCl (pH 3-4) and 6:1 (v/v) n-butyl alcohol/ethyl acetate. The intensity of the matrix-based peak at 731 cm⁻¹ was set at 100 as a basis for the feeds, and the peak at 707 cm-1 was the characteristic peak of melamine used in the calculations. Sufficient linearity was obtained in the range 2-10 µg·g⁻¹ (R² = 0.991). Limits of detection and quantification in the feeds were 0.5 and 2 µg·g⁻¹, respectively. The recovery rates were 82.5-90.2% with coefficients of variation below 4.02%. This new protocol could be easily developed for the routine monitoring of on-site feed quality and market surveillance.

| S-EPMC4171497 | biostudies-literature

Volumetric chemical imaging by clearing-enhanced stimulated Raman scattering microscopy.

Project description:Three-dimensional visualization of tissue structures using optical microscopy facilitates the understanding of biological functions. However, optical microscopy is limited in tissue penetration due to severe light scattering. Recently, a series of tissue-clearing techniques have emerged to allow significant depth-extension for fluorescence imaging. Inspired by these advances, we develop a volumetric chemical imaging technique that couples Raman-tailored tissue-clearing with stimulated Raman scattering (SRS) microscopy. Compared with the standard SRS, the clearing-enhanced SRS achieves greater than 10-times depth increase. Based on the extracted spatial distribution of proteins and lipids, our method reveals intricate 3D organizations of tumor spheroids, mouse brain tissues, and tumor xenografts. We further develop volumetric phasor analysis of multispectral SRS images for chemically specific clustering and segmentation in 3D. Moreover, going beyond the conventional label-free paradigm, we demonstrate metabolic volumetric chemical imaging, which allows us to simultaneously map out metabolic activities of protein and lipid synthesis in glioblastoma. Together, these results support volumetric chemical imaging as a valuable tool for elucidating comprehensive 3D structures, compositions, and functions in diverse biological contexts, complementing the prevailing volumetric fluorescence microscopy.

| S-EPMC6452712 | biostudies-literature

Assessing telomere length using surface enhanced Raman scattering.

Project description:Telomere length can provide valuable insight into telomeres and telomerase related diseases, including cancer. Here, we present a brand-new optical telomere length measurement protocol using surface enhanced Raman scattering (SERS). In this protocol, two single strand DNA are used as SERS probes. They are labeled with two different Raman molecules and can specifically hybridize with telomeres and centromere, respectively. First, genome DNA is extracted from cells. Then the telomere and centromere SERS probes are added into the genome DNA. After hybridization with genome DNA, excess SERS probes are removed by magnetic capturing nanoparticles. Finally, the genome DNA with SERS probes attached is dropped onto a SERS substrate and subjected to SERS measurement. Longer telomeres result in more attached telomere probes, thus a stronger SERS signal. Consequently, SERS signal can be used as an indicator of telomere length. Centromere is used as the inner control. By calibrating the SERS intensity of telomere probe with that of the centromere probe, SERS based telomere measurement is realized. This protocol does not require polymerase chain reaction (PCR) or electrophoresis procedures, which greatly simplifies the detection process. We anticipate that this easy-operation and cost-effective protocol is a fine alternative for the assessment of telomere length.

| S-EPMC4225564 | biostudies-literature

Surface-enhanced Raman scattering based ligase detection reaction.

Project description:Genomics provides a comprehensive view of the complete genetic makeup of an organism. Individual sequence variations, as manifested by single nucleotide polymorphisms (SNPs), can provide insight into the basis for a large number of phenotypes and diseases including cancer. The ability rapidly screen for SNPs will have a profound impact on a number of applications, most notably personalized medicine. Here we demonstrate a new approach to SNP detection through the application of surface-enhanced Raman scattering (SERS) to the ligase detection reaction (LDR). The reaction uses two LDR primers, one of which contains a Raman enhancer and the other a reporter dye. In LDR, one of the primers is designed to interrogate the SNP. When the SNP being interrogated matches the discriminating primer sequence, the primers are ligated and the enhancer and dye are brought into close proximity enabling the dye's Raman signature to be detected. By detecting the Raman signature of the dye rather than its fluorescence emission, our technique avoids the problem of spectral overlap which limits number of reactions which can be carried out in parallel by existing systems. We demonstrate the LDR-SERS reaction for the detection of point mutations in the human K-ras oncogene. The reaction is implemented in an electrokinetically active microfluidic device that enables physical concentration of the reaction products for enhanced detection sensitivity and quantization. We report a limit of detection of 20 pM of target DNA with the anticipated specificity engendered by the LDR platform.

| S-EPMC2716065 | biostudies-literature

Recent Progress in Surface-Enhanced Raman Scattering for the Detection of Chemical Contaminants in Water.

Project description:Water is a matter of vital importance for all developed countries due to the strong impact on human health and aquatic, wetlands and terrestrial environments. Therefore, the monitoring of water quality is of tremendous importance. The enormous advantages that Surface-enhanced Raman scattering (SERS) spectroscopy offers, such as fingerprint recognition, multiplex capabilities, high sensitivity, and selectivity or non-destructive testing, make this analytical tool very attractive for this purpose. This minireview aims to provide a summary of current approaches for the implementation of SERS sensors in monitoring organic and inorganic pollutants in water. In addition, we briefly highlight current challenges and provide an outlook for the application of SERS in environmental monitoring.

| S-EPMC7296159 | biostudies-literature

Plasmon-enhanced stimulated Raman scattering microscopy with single-molecule detection sensitivity.

Project description:Stimulated Raman scattering (SRS) microscopy allows for high-speed label-free chemical imaging of biomedical systems. The imaging sensitivity of SRS microscopy is limited to ~10?mM for endogenous biomolecules. Electronic pre-resonant SRS allows detection of sub-micromolar chromophores. However, label-free SRS detection of single biomolecules having extremely small Raman cross-sections (~10-30?cm2 sr-1) remains unreachable. Here, we demonstrate plasmon-enhanced stimulated Raman scattering (PESRS) microscopy with single-molecule detection sensitivity. Incorporating pico-Joule laser excitation, background subtraction, and a denoising algorithm, we obtain robust single-pixel SRS spectra exhibiting single-molecule events, verified by using two isotopologues of adenine and further confirmed by digital blinking and bleaching in the temporal domain. To demonstrate the capability of PESRS for biological applications, we utilize PESRS to map adenine released from bacteria due to starvation stress. PESRS microscopy holds the promise for ultrasensitive detection and rapid mapping of molecular events in chemical and biomedical systems.

| S-EPMC6872561 | biostudies-literature

Fiber-Enhanced Stimulated Raman Scattering and Sensitive Detection of Dilute Solutions.

Project description:Stimulated Raman scattering (SRS) is known to gain coherent amplification of molecular vibrations that allow for rapid and label-free chemical imaging in the microscopy setting. However, the tightly focused laser spot has limited the detection sensitivity, partly due to the tiny interaction volume. Here, we report the use of metal-lined hollow-core fiber (MLHCF) to improve the sensitivity of SRS in sensing dilute solutions by extending the light-matter interaction volume through the fiber waveguide. With a focusing lens (100 mm FL) and 320 μm diameter fiber, we demonstrated an optimum enhancement factor of ~20 at a fiber length of 8.3 cm. More importantly, the MLHCF exhibited a significantly suppressed cross-phase modulation (XPM) background, enabling the detection of ~0.7 mM DMSO in water. Furthermore, the relationship between fiber length and SRS signal could be well explained theoretically. The fiber-enhanced SRS (FE-SRS) method may be further optimized and bears potential in the sensitive detection of molecules in the solution and gas phases.

| S-EPMC9028131 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data