Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Localized Surface Plasmon Resonance of Silver Nanotriangles Synthesized by a Versatile Solution Reaction.

ABSTRACT: The surface plasmon resonance (SPR) of silver nanoparticles can be tuned throughout the visible and near-infrared region by their shape and size. Considering SPR applications, an easy and controllable method for preparing the silver nanocrystals with defined shape and size, is necessary. In this work, the triangular silver nanoplates were synthesized by reducing Ag(+) ions with ascorbic acid in the presence of silver seeds and poly(vinylpyrrolidone) (PVP) at room temperature. Both the seeds (as the nucleation sites) and PVP (as the capping reagent) played an important role in determining the edge length of the silver nanotriangles. The SPR of silver nanotriangles showed three distinct bands corresponding to the in-plane dipole, quadrupole, and out-plane quadrupole plasmon resonance, and the SPR shifted to shorter wavelengths with the decreased edge length of the silver nanotriangles as the theoretical calculation.

SUBMITTER: Wu C

PROVIDER: S-EPMC4560725 | biostudies-other | 2015 Dec

REPOSITORIES: biostudies-other

ACCESS DATA

Json Xml

Publications

Localized Surface Plasmon Resonance of Silver Nanotriangles Synthesized by a Versatile Solution Reaction.

Wu Chunfang C Zhou Xue X Wei Jie J

Nanoscale research letters 20150904 1

The surface plasmon resonance (SPR) of silver nanoparticles can be tuned throughout the visible and near-infrared region by their shape and size. Considering SPR applications, an easy and controllable method for preparing the silver nanocrystals with defined shape and size, is necessary. In this work, the triangular silver nanoplates were synthesized by reducing Ag(+) ions with ascorbic acid in the presence of silver seeds and poly(vinylpyrrolidone) (PVP) at room temperature. Both the seeds (as ...[more]

PMID: 26340946

Similar Datasets

Colorimetric Detection Based on Localized Surface Plasmon Resonance Optical Characteristics for Sensing of Mercury Using Green-Synthesized Silver Nanoparticles.

Project description:Development of selective colorimetric detectors that can use green-fabricated silver nanoparticles' (AgNPs) with localized surface plasmon resonances (LSPRs) to rapidly, simply, and selectively detect Hg(II) ions was undertaken in this study. Onion extract was used for synthesising photo-induced green crystalline silver nanoparticles (NPs). The formation of nanoparticles is enhanced when ultrasound irradiation is present; bioligands could serve as stabilizing and reducing agents. Different methods of measurement, including UV-Vis, TEM, SEM/EDAX, FT - IR, and XRD, are effective for characterization of nanoparticles. The spherical nature of green-fabricated AgNPs is confirmed by TEM. High-density, spherical, and uniformly formed silver nanoparticle shapes were found in silver nanoparticle SEM images. The arrangement of AgNPs in the form of face-centered cubic structures was confirmed by XRD patterns. The formation of impurity-free AgNPs was confirmed using the EDAX analysis results. Hg2+ with excellent sensitivity was sensitively and selectively detected by employing green-synthesized silver nanoparticles. The reduction of Ag (1) to Ag (0) was confirmed by a slight increase in Hg (II) concentration and progressive reduction of green-synthesized AgNPs, whose absorbance changed abruptly. The reduction of LSPRs by the phosphate buffer medium enables AgNPs to sensitively and selectively detect Hg2+ ions by providing good environment. Besides, a selective, sensitive, simple, and rapid method that is proposed for detecting Hg (II) ions in samples of water is presented in the study. Harmful mercury ions in real samples of water (tap and ground water) can colorimetrically and selectively be detected using the?AgNPs. The results showed an RSD of below 6% and over 92% of good recovery.

| S-EPMC7201495 | biostudies-literature

Tuning Localized Surface Plasmon Resonance Wavelengths of Silver Nanoparticles by Mechanical Deformation.

Project description:We describe a simple technique to alter the shape of silver nanoparticles (AgNPs) by rolling a glass tube over them to mechanically compress them. The resulting shape change in turn induces a red-shift in the localized surface plasmon resonance (LSPR) scattering spectrum and exposes new surface area. The flattened particles were characterized by optical and electron microscopy, single nanoparticle scattering spectroscopy, and surface enhanced Raman spectroscopy (SERS). AFM and SEM images show that the AgNPs deform into discs; increasing the applied load from 0 to 100 N increases the AgNP diameter and decreases the height. This deformation caused a dramatic red shift in the nanoparticle scattering spectrum and also generated new surface area to which thiolated molecules could attach as evident from SERS measurements. The simple technique employed here requires no lithographic templates and has potential for rapid, reproducible, inexpensive and scalable tuning of nanoparticle shape, surface area, and resonance while preserving particle volume.

| S-EPMC5325716 | biostudies-literature

A miRNA biosensor based on localized surface plasmon resonance enhanced by surface-bound hybridization chain reaction.

Project description:The dysregulation of the concentration of individual circulating microRNAs or small sets of them has been recognized as a marker of disease. For example, an increase of the concentration of circulating miR-17 has been linked to lung cancer and metastatic breast cancer, while its decrease has been found in multiple sclerosis and gastric cancer. Consequently, techniques for the fast, specific and simple quantitation of microRNAs are becoming crucial enablers of early diagnosis and therapeutic follow-up. DNA based biosensors can serve this purpose, overcoming some of the drawbacks of conventional lab-based techniques. Herein, we report a cost-effective, simple and robust biosensor based on localized surface plasmon resonance and hybridization chain reaction. Immobilized gold nanoparticles are used for the detection of miR-17. Specificity of the detection was achieved by the use of hairpin surface-tethered probes and the hybridization chain reaction was used to amplify the detection signal and thus extend the dynamic range of the quantitation. Less than 1 h is needed for the entire procedure that achieved a limit of detection of about 1 pM or 50 amol/measurement, well within the reported useful range for diagnostic applications. We suggest that this technology could be a promising substitute of traditional lab-based techniques for the detection and quantification of miRNAs after these are extracted from diagnostic specimens and their analysis is thus made possible.

| S-EPMC7395652 | biostudies-literature

Whole-Cell Pseudomonas aeruginosa Localized Surface Plasmon Resonance Aptasensor.

Project description:The detection of whole-cell Pseudomonas aeruginosa presents an intriguing challenge with direct applications in health care and the prevention of nosocomial infection. To address this problem, a localized surface plasmon resonance (LSPR) based sensing platform was developed to detect whole-cell Pseudomonas aeruginosa strain PAO1 using a surface-confined aptamer as an affinity reagent. Nanosphere lithography (NSL) was used to fabricate a sensor surface containing a hexagonal array of Au nanotriangles. The sensor surface was subsequently modified with biotinylated polyethylene glycol (Bt-PEG) thiol/PEG thiol (1:3), neutravidin, and biotinylated aptamer in a sandwich format. The 1:3 (v/v) ratio of Bt-PEG thiol/PEG thiol was specifically chosen to maximize PAO1 binding while minimizing nonspecific adsorption and steric hindrance. In contrast to prior whole-cell LSPR work, the LSPR wavelength shift was shown to be linearly related to bacterial concentration over the range of 10-103 cfu mL-1. This LSPR sensing platform is rapid (?3 h for detection), sensitive (down to the level of a single bacterium), selective for detection of Pseudomonas strain PAO1 over other strains, and exhibits a clinically relevant dynamic range and excellent shelf life (?2 months) when stored at ambient conditions. This versatile LSPR sensing platform should be extendable to a wide range of supermolecular analytes, including both bacteria and viruses, by switching affinity reagents, and it has potential to be used in point-of-care and field-based applications.

| S-EPMC5907805 | biostudies-literature

A localized surface plasmon resonance imaging instrument for multiplexed biosensing.

Project description:Localized surface plasmon resonance (LSPR) spectroscopy has been widely used for label-free, highly sensitive measurements of interactions at a surface. LSPR imaging (LSPRi) has the full advantages of LSPR but enables high-throughput, multiplexed measurements by simultaneously probing multiple individually addressable sensors on a single sample surface. Each spatially distinct sensor can be tailored to provide data regarding different surface functionalities or reaction environments. Previously, LSPRi has focused on single-particle sensing where the size scale is very small. Here, we create defined macroscale arrays of nanoparticles that are compatible with common patterning methods such as dip-pen nanolithography and multichannel microfluidic delivery devices. With this new LSPR sensing format, we report the first demonstration of multiplexed LSPR imaging and show that the increased throughput of our instrument enables the collection of a complete Langmuir binding curve on a single sensor surface. In addition, the multiplexed LSPR sensor is highly selective, as demonstrated by the hybridization of single-stranded DNA to complementary sequences immobilized on the sensor surface. The LSPR arrays described in this work exhibit uniform sensitivity and tailorable optical properties, making them an ideal platform for high-throughput, label-free analysis of a variety of molecular binding interactions.

| S-EPMC3696404 | biostudies-literature

Gas sensing with high-resolution localized surface plasmon resonance spectroscopy.

Project description:We report the first inert gas sensing and characterization studies based on high-resolution localized surface plasmon resonance (HR-LSPR) spectroscopy. HR-LSPR was used to detect the extremely small changes (<3 × 10(-4)) in bulk refractive index when the gas was switched between He(g) and Ar(g) or He(g) and N2(g). We also demonstrate submonolayer sensitivity to adsorbed water from exposure of the sensor to air (40% humidity) versus dry N2(g). These measurements significantly expand the applications space and characterization tools for plasmonic nanosensors.

| S-EPMC3084350 | biostudies-literature

Au-WO3 Nanocomposite Coatings for Localized Surface Plasmon Resonance Sensing.

Project description:Localized surface plasmon resonance (LSPR) gas sensors are gaining increasing importance due to their unique tuneable functional properties. Au-WO3-x nanocomposite coatings, in particular, can be outstandingly sensitive to many different gases. However, a proper understanding of their optical properties and the way in which those properties are correlated to their structure/microstructure, is still needed. In this work, Au-WO3 nanocomposite coatings, with Au contents between 0-11 atomic percent, were grown using reactive magnetron co-sputtering technique and were characterized concerning their optical response. The precipitation of Au nanoparticles in the oxide matrix was promoted through thermal annealing treatments until 500 °C. Along with the Au nanoparticles' morphological changes, the annealing treatments stimulated the crystallization of WO3, together with the appearance of oxygen-deficient WO3-x phases. Through theoretical simulations, we have related the LSPR effect with the different structural and morphological variations (namely, size and distribution of the nanoparticles and their local environment), which were a function of the Au content and annealing temperature. Our results suggest that local voids were present in the vicinity of the Au nanoparticles, for all temperature range, and that they should be present in a wide variety of Au-WO3 nanocomposites. A theoretical study concerning the refractive index sensitivity was carried out in order to predict the optimal coating design parameters for gas sensing experiments.

| S-EPMC6981964 | biostudies-literature

Temperature-Sensitive Localized Surface Plasmon Resonance of α-NiS Nanoparticles.

Project description:The presented work shows a synthesis route to obtain nanoparticles of the hexagonal α-NiS phase and core-shell particles where the same material is grown onto previously prepared Au seeds. In the bulk, this nickel sulfide phase is known to exhibit a metal-insulator type phase transition (MIT) at 265 K which drastically alters its electrical conductivity. Since the produced nanoparticles show a localized surface plasmon resonance (LSPR) in the visible range of the electromagnetic spectrum, the development of their optical properties depending on the temperature is investigated. This is the first time an LSPR of colloidal nanoparticles is monitored regarding such a transition. The results of UV-vis absorbance measurements show that the LSPR of the particles can be strongly and reversibly tuned by varying the temperature. It can be switched off by cooling the nanoparticles and switched on again by reheating them above the transition temperature. Additional to the phase transition, the temperature-dependent magnetic susceptibility of α-NiS and Au-NiS nanoparticles suggests the presence of different amounts of uncompensated magnetic moments in these compounds that possibly affect the optical properties and may cause the observed quantitative differences in the LSPR response of these materials.

| S-EPMC8667038 | biostudies-literature

Surface plasmon resonance-induced stiffening of silver nanowires.

Project description:We report the results of a computational, atomistic electrodynamics study of the effects of electromagnetic waves on the mechanical properties, and specifically the Young's modulus of silver nanowires. We find that the Young's modulus of the nanowires is strongly dependent on the optical excitation energy, with a peak enhancement occurring at the localized surface plasmon resonance frequency. When the nanowire is excited at the plasmon resonance frequency, the Young's modulus is found to increase linearly with increasing nanowire aspect ratio, with a stiffening of nearly 15% for a 2 nm cross section silver nanowire with an aspect ratio of 3.5. Furthermore, our results suggest that this plasmon resonance-induced stiffening is stronger for larger diameter nanowires for a given aspect ratio. Our study demonstrates a novel approach to actively tailoring and enhancing the mechanical properties of metal nanowires.

| S-EPMC4448551 | biostudies-other

Direct observation of aminoglycoside-RNA binding by localized surface plasmon resonance spectroscopy.

Project description:RNA is involved in fundamental biological functions when bacterial pathogens replicate. Identifying and studying small molecules that can interact with bacterial RNA and interrupt cellular activities is a promising path for drug design. Aminoglycoside (AMG) antibiotics, prominent natural products that recognize RNA specifically, exert their biological functions by binding to prokaryotic ribosomal RNA and interfering with protein translation, ultimately resulting in bacterial cell death. The decoding site, a small internal loop within the 16S rRNA, is the molecular target for the AMG antibiotics. The specificity of neomycin B, a highly potent AMG antibiotic, to the ribosomal decoding RNA site, was previously studied by observing AMG-RNA complexes in solution. Here, we study this interaction using localized surface plasmon resonance (LSPR) transducers comprising gold island films prepared by evaporation on glass and annealing. Small molecule AMG receptors were immobilized on the Au islands via polyethylene glycol (PEG)-thiol linkers, and the interaction with target RNA in solution was studied by monitoring the change in the LSPR optical response upon binding. The results show high-affinity binding of neomycin to 27-nucleotide model A-site RNA sequence in the nanomolar range, while no specific binding is observed for synthetic RNA oligomers (e.g., poly-U). The impact of specific base substitutions in the A-site RNA constructs on binding affinity and selectivity is determined quantitatively. It is concluded that LSPR is a powerful tool for providing molecular insight into small molecule-RNA interactions and for the design and screening of selective antimicrobial drugs.

| S-EPMC3581361 | 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