Toward quantitative SERS detection in low analyte concentration by investigating the immersion volume and time of SERS substrate in analyte solution

We introduce low-cost, tunable, hybrid SERS substrate of commercial gold nanoparticles on untreated aluminum foil (AuNPs@AlF). Two or three AuNP centrifugation/resuspension cycles are proven to be critical in the assay preparation. The limits of detection (LODs) for 4-nitrobenzenethiol (NBT) and crystal violet (CV) on this substrate are about 0.12 nM and 0.19 nM, respectively, while maximum analytical SERS enhancement factors (AEFs) are about 107. In comparative assays LODs for CV measured on AuNPs@Au film and AuNPs@glass are about 0.35 nM and 2 nM, respectively. The LOD for melamine detected on AuNPs@ Al foil is 27 ppb with 3 orders of magnitude for linear response range. Overall, AuNPs@AlF demonstrated competitive performance in comparison with AuNPs@ Au film substrate in SERS detection of CV, NBT, and melamine. To check the versatility of the AuNPs@AlF substrate we also detected KNO3 with LODs of 0.7 mM and SERS EF around 2 × 103, which is on the same order with SERS EF reported for this compound in the literature.

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

Biosensors ◽

10.3390/bios9030091 ◽

2019 ◽

Vol 9 (3) ◽

pp. 91 ◽

Cited By ~ 5

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.

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Preparation of Hydrophobic Film by Electrospinning for Rapid SERS Detection of Trace Triazophos

Sensors ◽

10.3390/s20154120 ◽

2020 ◽

Vol 20 (15) ◽

pp. 4120

Author(s):

Fei Shao ◽

Jiaying Cao ◽

Ye Ying ◽

Ying Liu ◽

Dan Wang ◽

...

Keyword(s):

Hot Spots ◽

Large Scale ◽

Limit Of Detection ◽

Small Region ◽

Sers Substrate ◽

Ag Nps ◽

Electrospinning Technique ◽

Heterocyclic Molecules ◽

Surface Enhanced Raman ◽

Sers Detection

For real application, it is an urgent demand to fabricate stable and flexible surface-enhanced Raman scattering (SERS) substrates with high enhancement factors in a large-scale and facile way. Herein, by using the electrospinning technique, a hydrophobic and flexible poly(styrene-co-butadiene) (SB) fibrous membrane is obtained, which is beneficial for modification of silver nanoparticles (Ag NPs) colloid in a small region and then formation of more “hot spots” by drying; the final SERS substrate is designated as Ag/SB. Hydrophobic Ag/SB can efficiently capture heterocyclic molecules into the vicinity of hot spots of Ag NPs. Such Ag/SB films are used to quantitatively detect trace triazophos residue on fruit peels or in the juice, and the limit of detection (LOD) of 2.5 × 10−8 M is achieved. Ag/SB films possess a capability to resist heat. As a case, 6-mercaptopurine (6MP) that just barely dissolves in 90 °C water is picked for conducting Ag/SB-film-based experiments.

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Gold nanocone arrays directly grown on nickel foam for improved SERS detection of aromatic dyes

Analytical Methods ◽

10.1039/c8ay00840j ◽

2018 ◽

Vol 10 (26) ◽

pp. 3170-3177 ◽

Cited By ~ 3

Author(s):

Fugang Xu ◽

Huasheng Lai ◽

Hui Xu

Keyword(s):

Nickel Foam ◽

Sensitive Detection ◽

Sers Substrate ◽

Ni Foam ◽

Sers Detection

An efficient SERS substrate composed of gold nanocone arrays with abundant sharp tips directly grown on 3D porous Ni foam (AuNCA@Ni foam) was developed for sensitive detection of aromatic dyes.

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Synergistic effects of photonic crystal and gold nanostars for quantitative SERS detection of 3-Phenoxybenzoic acid

Applied Surface Science ◽

10.1016/j.apsusc.2019.01.061 ◽

2019 ◽

Vol 476 ◽

pp. 587-593 ◽

Cited By ~ 9

Author(s):

He Wang ◽

Yanjie Wu ◽

Hongwei Song

Keyword(s):

Photonic Crystal ◽

Synergistic Effects ◽

Gold Nanostars ◽

Sers Detection ◽

Quantitative Sers

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Electrospun magnetic CoFe2O4/Ag hybrid nanotubes for sensitive SERS detection and monitoring of the catalytic degradation of organic pollutants

RSC Advances ◽

10.1039/c7ra07786f ◽

2017 ◽

Vol 7 (64) ◽

pp. 40334-40341 ◽

Cited By ~ 7

Author(s):

Wei Song ◽

Zezhou Yang ◽

Fuqiu Ma ◽

Maoqiang Chi ◽

Bing Zhao ◽

...

Keyword(s):

Organic Pollutants ◽

Degradation Process ◽

Catalytic Degradation ◽

Sers Substrate ◽

Sers Detection

We report on the synthesis of magnetic CoFe2O4/Ag hybrid nanotubes as both SERS substrate and catalyst to monitor the catalytic degradation process of organic pollutants.

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Functionalized Gold Nanoparticles Coated Polymer Spheres as SERS Substrate for the Detection of TNT Explosives

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.924.366 ◽

2014 ◽

Vol 924 ◽

pp. 366-370 ◽

Cited By ~ 3

Author(s):

Hai Xin Gu ◽

Lin Xue ◽

Ya Heng Zhang ◽

Yong Feng Zhang ◽

Li Ying Cao

Keyword(s):

Gold Nanoparticles ◽

Sodium Citrate ◽

Polymer Surface ◽

Sers Substrate ◽

Conjugation System ◽

Sers Detection ◽

Polymer Sphere ◽

Real World Situation ◽

Tnt Detection ◽

Polymer Spheres

In this paper, we fabricated the 4-aminobenzenethiol modified gold nanoparticles onto polymer spheres as SERS substrate to selectively detect 2,4,6-trinitrotoluene (TNT) explosives. The gold nanoseeds were fixed on polymer surface by reduction of HAuCl4·3H2O with sodium citrate. About 60~100nm nanoparticles were formed from the previous seeds and self-assembled by 4-aminobenzenethiol. The functionalized gold nanopartilces aggregation coated on large polymer sphere surface not only absorbed more TNT molecules via conjugation system, but also generated numerous "hot spots". It was demonstrated that this substrate displayed high SERS activity for TNT detection. It could also be anticipated that the aforementioned material would be used for fast and sensitive SERS detection of TNT in real-world situation. Keywords: gold nanopartilces, SERS, TNT, functionalization

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Quantitative SERS Detection of Trace Glutathione with Internal Reference Embedded Au-core/Ag-shell Nanoparticles

Nano LIFE ◽

10.1142/s1793984416420034 ◽

2016 ◽

Vol 06 (03n04) ◽

pp. 1642003 ◽

Cited By ~ 2

Author(s):

Yan Zhou ◽

Rui Ding

Keyword(s):

Reference Method ◽

High Sensitivity ◽

Internal Reference ◽

Shell Nanoparticles ◽

New Strategy ◽

Surface Enhanced Raman ◽

Sers Detection ◽

Quantitative Sers ◽

Shell Particles ◽

Improved Accuracy

Surface-enhanced Raman scattering (SERS) has been widely studied and applied for over three decades. However, reliable SERS detection of molecules with low polarizability is still suffering from poor sensitivity and reproducibility. In this paper, we have reported a new strategy for performing quantitative SERS detection of Raman insensitive Glutathione (GSH), based on GSH-induced replacement of a highly Raman sensitive four-mercaptopyridine (MP) adsorbed on the surface of four-aminothiophenol (ATP) embedded Au-core/Ag-shell particles. This replacement led to a strong decrease of the MP SERS signal, which was used to determine the concentration of GSH. The adoption of GSH-induced Raman probe replacement leads to high sensitivity, while the use of internal reference method provides an improved accuracy of the GSH quantification.

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