Grating-like SERS substrate with tunable gaps based on nanorough Ag nanoislands/moth wing scale arrays for quantitative detection of cypermethrin

2018 ◽  
Vol 26 (17) ◽  
pp. 22168 ◽  
Author(s):  
Yuhong Wang ◽  
Mingli Wang ◽  
Xin Sun ◽  
Guochao Shi ◽  
Jinzan Zhang ◽  
...  
Keyword(s):  
Quantitative Detection ◽  
Sers Substrate ◽  
Wing Scale

scholarly journals Application of Aluminum Hydroxide for Improvement of Label-Free SERS Detection of Some Cephalosporin Antibiotics in Urine

Biosensors ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 91 ◽  
Author(s):  
Natalia E. Markina ◽  
Alexey V. Markin
Keyword(s):  
Aluminum Hydroxide ◽  
Surface Enhanced Raman Spectroscopy ◽  
Negative Influence ◽  
Quantitative Detection ◽  
Therapeutic Drug ◽  
Excitation Wavelength ◽  
Sers Substrate ◽  
Label Free ◽  
Surface Enhanced Raman ◽  
Sers Detection

This report is dedicated to development of surface-enhanced Raman spectroscopy (SERS) based analysis protocol for detection of antibiotics in urine. The key step of the protocol is the pretreatment of urine before the detection to minimize background signal. The pretreatment includes extraction of intrinsic urine components using aluminum hydroxide gel (AHG) and further pH adjusting of the purified sample. The protocol was tested by detection of a single antibiotic in artificially spiked samples of real urine. Five antibiotics of cephalosporin class (cefazolin, cefoperazone, cefotaxime, ceftriaxone, and cefuroxime) were used for testing. SERS measurements were performed using a portable Raman spectrometer with 638 nm excitation wavelength and silver nanoparticles as SERS substrate. The calibration curves of four antibiotics (cefuroxime is the exception) cover the concentrations required for detection in patient’s urine during therapy (25/100‒500 μg/mL). Random error of the analysis (RSD < 20%) and limits of quantification (20‒90 μg/mL) for these antibiotics demonstrate the applicability of the protocol for reliable quantitative detection during therapeutic drug monitoring. The detection of cefuroxime using the protocol is not sensitive enough, allowing only for qualitative detection. Additionally, time stability and batch-to-batch reproducibility of AHG were studied and negative influence of the pretreatment protocol and its limitations were estimated and discussed.

scholarly journals Insight into the working wavelength of hotspot effects generated by popular nanostructures

2019 ◽  
Vol 8 (1) ◽  
pp. 24-34 ◽  
Author(s):  
Zhong Wang ◽  
Kesu Cai ◽  
Yang Lu ◽  
Haining Wu ◽  
Yuee Li ◽  
...  
Keyword(s):  
Electric Field ◽  
Field Enhancement ◽  
Quantitative Detection ◽  
Excitation Wavelength ◽  
Sers Substrate ◽  
Nanorod Arrays ◽  
Electric Field Enhancement ◽  
Incident Laser ◽  
Incident Wavelength ◽  
Excitation Laser

Abstract A proper excitation wavelength is much important for the application of surface-enhanced Raman spectroscopy (SERS) in the biochemical field. Here, based on a SERS substrate model with an incident Gaussian beam, we investigate the dependence of the electric field enhancement on the incident wavelength of the excitation laser for popular nanostructures, including nanosphere dimer, nanorod dimer, and nanorod arrays. The results in the present manuscript indicate that both the nanosphere and nanorod dimer present a much broader plasmonic excitation wavelength range extending to the near-infrared region. The enhancement effect of Nanorod arrays is strongly dependent on the incident direction of excitation light. Finally, according to the conclusions above, a SERS substrate consisting of nanocubes based on the SPP eigen-mode is proposed and the electric field enhancement is homogeneous, and insensitive to the polarization of the incident laser. The enhancement factor is not ultrahigh; however, good homogeneousness permits for quantitative detection of lower concentration components in mixtures. Graphical abstract: By investigating the dependence of the electric field enhancement on the incident wavelength of the excitation laser for popular nanostructures, we propose a SERS substrate consisting of Au nanocubes based on the SPP eigenmode. The electric field enhancement is homogeneous, and insensitive to the polarization of the incident laser. Though the enhancement factor is not ultrahigh, good homogeneousness permits for quantitative detection of lower concentration components in mixtures.

Bacteria Inspired Internal Standard SERS Substrate for Quantitative Detection

2020 ◽  
Author(s):  
Jiawei Liu ◽  
Zilan Hong ◽  
Weimin Yang ◽  
Chen Liu ◽  
Zhicheng Lu ◽  
...  
Keyword(s):  
Internal Standard ◽  
Quantitative Detection ◽  
Sers Substrate

Quantitative detection of crystal violet using a surface-enhanced Raman scattering based on flower-like HAp/Ag nanocomposite

2021 ◽  
Author(s):  
Yamin Lin ◽  
Mengmeng Zheng ◽  
Xin Zhao ◽  
Dan Liu ◽  
Jiamin Gao ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Raman Scattering ◽  
Crystal Violet ◽  
Quantitative Detection ◽  
Sers Substrate ◽  
One Pot ◽  
Highly Sensitive ◽  
Surface Enhanced ◽  
Surface Enhanced Raman ◽  
Enhanced Raman Scattering

Herein, we proposed a simple one-pot sol-thermal strategy to prepare highly sensitive and reproducible SERS substrate. The silver-doped hydroxyapatite nanocomposite (HAp/Ag) could suppress the oxidation of the silver nanoparticles, which...

scholarly journals Detection of Chloroalkanes by Surface-Enhanced Raman Spectroscopy in Microfluidic Chips

Sensors ◽  
2018 ◽  
Vol 18 (10) ◽  
pp. 3212 ◽  
Author(s):  
Zdeněk Pilát ◽  
Martin Kizovský ◽  
Jan Ježek ◽  
Stanislav Krátký ◽  
Jaroslav Sobota ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Gold Surface ◽  
Surface Enhanced Raman Spectroscopy ◽  
Microfluidic System ◽  
Environmental Pollutant ◽  
Spectral Lines ◽  
Quantitative Detection ◽  
Sers Substrate ◽  
Surface Enhanced ◽  
Surface Enhanced Raman

Optofluidics, a research discipline combining optics with microfluidics, currently aspires to revolutionize the analysis of biological and chemical samples, e.g., for medicine, pharmacology, or molecular biology. In order to detect low concentrations of analytes in water, we have developed an optofluidic device containing a nanostructured substrate for surface enhanced Raman spectroscopy (SERS). The geometry of the gold surface allows localized plasmon oscillations to give rise to the SERS effect, in which the Raman spectral lines are intensified by the interaction of the plasmonic field with the electrons in the molecular bonds. The SERS substrate was enclosed in a microfluidic system, which allowed transport and precise mixing of the analyzed fluids, while preventing contamination or abrasion of the highly sensitive substrate. To illustrate its practical use, we employed the device for quantitative detection of persistent environmental pollutant 1,2,3-trichloropropane in water in submillimolar concentrations. The developed sensor allows fast and simple quantification of halogenated compounds and it will contribute towards the environmental monitoring and enzymology experiments with engineered haloalkane dehalogenase enzymes.

scholarly journals Detection of Chloroalkanes by Surface-Enhanced Raman Spectroscopy in Microfluidic Chip

2018 ◽  
Author(s):  
Zdeněk Pilát ◽  
Martin Kizovský ◽  
Jan Ježek ◽  
Stanislav Krátký ◽  
Jaroslav Sobota ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Gold Surface ◽  
Surface Enhanced Raman Spectroscopy ◽  
Microfluidic System ◽  
Environmental Pollutant ◽  
Spectral Lines ◽  
Quantitative Detection ◽  
Sers Substrate ◽  
Surface Enhanced ◽  
Surface Enhanced Raman

Optofluidics, a research discipline combining optics with microfluidics, currently aspires to revolutionize the analysis of biological and chemical samples e.g. for medicine, pharmacology, or molecular biology. In order to detect low concentrations of analytes in water, we developed an optofluidic device containing a nanostructured substrate for surface enhanced Raman spectroscopy (SERS). The geometry of the gold surface allows localized plasmon oscillations to give rise to the SERS effect, in which the Raman spectral lines are intensified by the interaction of the plasmonic field with the electrons in the molecular bonds. The SERS substrate was enclosed in a microfluidic system, which allowed transport and precise mixing of the analyzed fluids, while preventing contamination or abrasion of the highly sensitive substrate. To illustrate its practical use, we employed the device for quantitative detection of persistent environmental pollutant 1,2,3-trichloropropane in water in submillimolar concentrations. The developed sensor allows fast and simple quantification of halogenated compounds and it will contribute towards the environmental monitoring and enzymology experiments with engineered haloalkane dehalogenase enzymes.

Therapeutic efficacy of some extracts of hot pepper fruits (Capsicum annuum) and Sumac seeds (Rhus coriaria) on the growth of some isolated dermatophytes species

2018 ◽  
Vol 1 (3) ◽  
pp. 52-62
Author(s):  
Sara Omran ◽  
Abdulghani Alsamarai ◽  
Firas Razzzaq
Keyword(s):  
Antifungal Activity ◽  
Fungal Infection ◽  
Aqueous Extract ◽  
Plant Extracts ◽  
Therapeutic Efficacy ◽  
Diffusion Method ◽  
Quantitative Detection ◽  
Hot Pepper ◽  
Alcoholic Extract ◽  
Dermatology Clinic

Background: Fungal infections are one of the common skin diseases with difficulty in their treatment approach. The present efficient drugs for fungal infection are limited. Aim: To determine the therapeutic efficacy of plant extracts as alternative antifungal agents. Materials and methods: 100 clinical samples [68 from female and 32 from male] were collected during the period from March to July 2017 from subjects attending Dermatology Clinic in Salah Uldean General Hospital. Fungal infection was diagnosed with using KOH wet preparation. Fungal species identified by using conventional approach. The active ingredients existing in the plant extracts were detected and analyzed through qualitative and quantitative detection technique of chemical compounds using a high performance liquid chromatographic device (HPLC). Agar diffusion method was used to determine antifungal activity of plant extracts. Results: Direct microscopic examination showed that there were (75%) positive samples, while culture shows (67%) positive samples. The isolated dermatophytes belong to Epidermophyoton, Microsporum, and Trichophyton genus. The predominant dermatophytes were T. rubrum (25%) species. The highest frequency of infection was in the age group of 11-20 years. The sensitivity of the tested fungi to the aqueous and alcoholic plant extracts varies. Alcoholic extract of the hot pepper plant was more effective as antifungal than the aqueous extract of the same plant. However, aqueous hot pepper extracts was more effective against T. mentagrophyte than that of alcoholic extract. Additionally, alcoholic Sumac extract shows higher efficacy that aqueous extract. Conclusion: Hot pepper and Sumac extracts show antifungal activity against Microsporum canis, Trichophyton rubrum and T. mentagrophyte.

Quantitative detection and imaging of soot particles by laser induced incandescence

1997 ◽  
Author(s):  
K. McManus ◽  
M. Allen ◽  
W. Rawlins ◽  
K. McManus ◽  
M. Allen ◽  
...  
Keyword(s):  
Quantitative Detection ◽  
Soot Particles ◽  
Laser Induced Incandescence
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