scholarly journals Hybrid Sol-Gel Surface-Enhanced Raman Sensor for Xylene Detection in Solution

Sensors ◽  
2021 ◽  
Vol 21 (23) ◽  
pp. 7912
Author(s):  
Verena Weber ◽  
Laura Brigo ◽  
Giovanna Brusatin ◽  
Giovanni Mattei ◽  
Danilo Pedron ◽  
...  
Keyword(s):  
Limit Of Detection ◽  
Sol Gel ◽  
Metallic Surfaces ◽  
Aromatic Molecules ◽  
Surface Enhanced ◽  
Gel Film ◽  
Volatile Organic ◽  
Surface Enhanced Raman ◽  
Raman Sensor

This paper reports on the fabrication and characterization of a plasmonic/sol-gel sensor for the detection of aromatic molecules. The sol-gel film was engineered using polysilsesquioxanes groups to capture the analyte, through π-π interaction, and to concentrate it close to the plasmonic surface, where Raman amplification occurs. Xylene was chosen as an analyte to test the sensor. It belongs to the general class of volatile organic compounds and can be found in water or in the atmosphere as pollutants released from a variety of processes; its detection with SERS is typically challenging, due to its low affinity toward metallic surfaces. The identification of xylene was verified in comparison with that of other aromatic molecules, such as benzene and toluene. Investigations were carried out on solutions of xylene in cyclohexane, using concentrations in the range from 0 to 800 mM, to evaluate the limit of detection (LOD) of about 40 mM.

Bacterial detection and differentiation via direct volatile organic compound sensing with surface enhanced Raman spectroscopy

2017 ◽  
Author(s):  
Caitlin S. DeJong ◽  
David I. Wang ◽  
Aleksandr Polyakov ◽  
Anita Rogacs ◽  
Steven J. Simske ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Bacterial Infections ◽  
Direct Detection ◽  
Point Of Care ◽  
Surface Enhanced Raman Spectroscopy ◽  
E Coli ◽  
Recent Emergence ◽  
Surface Enhanced ◽  
Volatile Organic ◽  
Surface Enhanced Raman

Through the direct detection of bacterial volatile organic compounds (VOCs), via surface enhanced Raman spectroscopy (SERS), we report here a reconfigurable assay for the identification and monitoring of bacteria. We demonstrate differentiation between highly clinically relevant organisms: <i>Escherichia coli</i>, <i>Enterobacter cloacae</i>, and <i>Serratia marcescens</i>. This is the first differentiation of bacteria via SERS of bacterial VOC signatures. The assay also detected as few as 10 CFU/ml of <i>E. coli</i> in under 12 hrs, and detected <i>E. coli</i> from whole human blood and human urine in 16 hrs at clinically relevant concentrations of 10<sup>3</sup> CFU/ml and 10<sup>4</sup> CFU/ml, respectively. In addition, the recent emergence of portable Raman spectrometers uniquely allows SERS to bring VOC detection to point-of-care settings for diagnosing bacterial infections.

scholarly journals Detection of Triphenylmethane Drugs in Fish Muscle by Surface-Enhanced Raman Spectroscopy Coupled with Au-Ag Core-Shell Nanoparticles

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Lu Pei ◽  
Yiqun Huang ◽  
Chunying Li ◽  
Yuanyuan Zhang ◽  
Barbara A. Rasco ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Malachite Green ◽  
Crystal Violet ◽  
Bimetallic Nanoparticles ◽  
Limit Of Detection ◽  
Fish Muscle ◽  
Surface Enhanced Raman Spectroscopy ◽  
Vis Spectroscopy ◽  
Surface Enhanced ◽  
Surface Enhanced Raman

Silver-coated gold bimetallic nanoparticles were synthesized and used as substrates for surface-enhanced Raman spectroscopy (SERS) in detecting prohibited triphenylmethane drugs (including crystal violet and malachite green) in fish muscle. The optical properties and physical properties of bimetallic nanospheres were characterized by UV-Vis spectroscopy and transmission electron microscopy. The optimal nanospheres selected had relatively uniform size (diameter: 33 ± 3 nm) with a silver layer coated on the surface of gold seed (diameter: 18 ± 2 nm). For both crystal violet and malachite green, characteristic SERS spectral features could be identified at concentration as low as 0.1 μg/L with these bimetallic nanospheres. Crystal violet and malachite green residues in fish muscle could also be detected at levels as low as 0.1 ng/g, which could meet the most restricted regulatory requirements for the limit of detection in terms of analytical methods for crystal violet or malachite green in fish muscle. This study provides a basis for applying SERS technology with bimetallic nanoparticles to the identification of trace amounts of prohibited substances in aquatic food products, and the methodology could be extended to analyses of other hazardous chemicals in complex food matrices like vegetables and meats.

scholarly journals Refractive index sensing and surface-enhanced Raman spectroscopy using silver–gold layered bimetallic plasmonic crystals

2017 ◽  
Vol 8 ◽  
pp. 2492-2503 ◽  
Author(s):  
Somi Kang ◽  
Sean E Lehman ◽  
Matthew V Schulmerich ◽  
An-Phong Le ◽  
Tae-woo Lee ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Refractive Index ◽  
Electric Fields ◽  
Surface Enhanced Raman Spectroscopy ◽  
Plasmonic Crystals ◽  
Metal Thickness ◽  
Surface Enhanced ◽  
Surface Enhanced Raman ◽  
Difference Time

Herein we describe the fabrication and characterization of Ag and Au bimetallic plasmonic crystals as a system that exhibits improved capabilities for quantitative, bulk refractive index (RI) sensing and surface-enhanced Raman spectroscopy (SERS) as compared to monometallic plasmonic crystals of similar form. The sensing optics, which are bimetallic plasmonic crystals consisting of sequential nanoscale layers of Ag coated by Au, are chemically stable and useful for quantitative, multispectral, refractive index and spectroscopic chemical sensing. Compared to previously reported homometallic devices, the results presented herein illustrate improvements in performance that stem from the distinctive plasmonic features and strong localized electric fields produced by the Ag and Au layers, which are optimized in terms of metal thickness and geometric features. Finite-difference time-domain (FDTD) simulations theoretically verify the nature of the multimode plasmonic resonances generated by the devices and allow for a better understanding of the enhancements in multispectral refractive index and SERS-based sensing. Taken together, these results demonstrate a robust and potentially useful new platform for chemical/spectroscopic sensing.

scholarly journals Detection and Differentiation of Avian Mycoplasmas by Surface-Enhanced Raman Spectroscopy Based on a Silver Nanorod Array

2011 ◽  
Vol 78 (6) ◽  
pp. 1930-1935 ◽  
Author(s):  
Suzanne L. Hennigan ◽  
Jeremy D. Driskell ◽  
Naola Ferguson-Noel ◽  
Richard A. Dluhy ◽  
Yiping Zhao ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Sensitivity And Specificity ◽  
Limit Of Detection ◽  
Direct Detection ◽  
Nanorod Array ◽  
Surface Enhanced Raman Spectroscopy ◽  
Mycoplasma Species ◽  
Content Type ◽  
Surface Enhanced ◽  
Surface Enhanced Raman

ABSTRACTMycoplasma gallisepticumis a bacterial pathogen of poultry that is estimated to cause annual losses exceeding $780 million. The National Poultry Improvement Plan guidelines recommend regular surveillance and intervention strategies to containM. gallisepticuminfections and ensure mycoplasma-free avian stocks, but several factors make detection ofM. gallisepticumand diagnosis ofM. gallisepticuminfection a major challenge. Current techniques are laborious, require special expertise, and are typically plagued by false results. In this study, we describe a novel detection strategy which uses silver nanorod array–surface-enhanced Raman spectroscopy (NA-SERS) for direct detection of avian mycoplasmas. As a proof of concept for use in avian diagnostics, we used NA-SERS to detect and differentiate multiple strains of avian mycoplasma species, includingAcholeplasma laidlawii,Mycoplasma gallinarum,Mycoplasma gallinaceum,Mycoplasma synoviae, andM. gallisepticum, including vaccine strains 6/85, F, and ts-11. Chemometric multivariate analysis of spectral data was used to classify these species rapidly and accurately, with >93% sensitivity and specificity. Furthermore, NA-SERS had a lower limit of detection that was 100-fold greater than that of standard PCR and comparable to that of real-time quantitative PCR. Detection ofM. gallisepticumin choanal cleft swabs from experimentally infected birds yielded good sensitivity and specificity, suggesting that NA-SERS is applicable for clinical detection.

Surface-enhanced Raman detection of CW agents in water using gold sol gel substrates

2002 ◽  
Author(s):  
W. Ranjith Premasiri ◽  
Richard H. Clarke ◽  
M. Edward Womble
Keyword(s):  
Sol Gel ◽  
Surface Enhanced ◽  
Surface Enhanced Raman ◽  
Gold Sol
Sign in / Sign up

Export Citation Format

Share Document