Analytical Methods
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2024
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IF 2.7
Kang Shen,Caili Bi,Haifan Yang,Miaowen Xu,Lili Huang,Youwei Wang
Based on the coordination principle of Lewis acid, the 4-mercaptophenylboronic acid (4-MPBA)-modified novel dumbbell-shaped Au-Ag nanorods (4-MPBA@DS Au-AgNRs) substrate has been developed, which could be combined with the surface-enhanced Raman scattering (SERS) technique to detect SO42- with high sensitivity and specificity. DS Au-AgNRs synthesized in this paper with dumbbell particular structure have been verified by finite-difference time domain (FDTD) simulation to be capable of stimulating strong localized electromagnetic enhancement (EM) at nano-edge, gap, generating a large number of “hot spots” exhibiting excellent SERS performance. The 4-MPBA modified on its surface could specifically recognize SO42-, producing a change in the spectral peak at 1382 cm-1, thus realizing highly sensitive and specific sensing of SO42-. Under optimized conditions, this SERS sensor responded rapidly to SO42- within 2 minutes and demonstrated uncommon immunity. Ratio calculation by the ratio of the characteristic peaks at 1382 and 1070 cm-1 (I1382/I1070) enabled quantitative detection of SO42- in the range of 1 × 10-8-1 × 10-3 M, and the detection threshold was as low as 1 nM, which was superior to that of similar detection methods. Importantly, the utility and reliability of this SERS substrate for the determination of SO42- in actual samples were evaluated using ion chromatography as the gold standard, and there was no significant difference between the two protocols (P > 0.05), and the RSD was less than 6% with a satisfactory recovery rate (97.6-102.3%). Therefore, the present protocol has the advantages of simplicity and rapidity, high sensitivity, specificity, stability, and practicability in the determination of SO42- in aqueous solution, providing a reliable solution for tracing SO42- in the field of food safety and environmental testing.
研究领域:
分析化学
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环境科学
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食品安全
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DOI
PubMed
高影响因子
Biosensors-Basel
·
2023
·Vol. 13
·期 8
·766
·
IF 5.4
Xiaoxiao Zhou,Shouhui Chen,Yi Pan,Yuanfeng Wang,Naifeng Xu,Yanwen Xue,Xinlin Wei,Ying Lu
In order to improve the detection performance of surface-enhanced Raman scattering (SERS), a low-cost Au@Ag nanorods (Au@Ag NRs) substrate with a good SERS enhancement effect was developed and applied to the detection of malachite green (MG) in aquaculture water and crayfish. By comparing the SERS signal enhancement effect of five kinds of Au@Ag NRs substrates with different silver layer thickness on 4-mercaptobenzoic acid (4-MBA) solution, it was found that the substrate prepared with 100 µL AgNO3had the smallest aspect ratio (3.27) and the thickest Ag layer (4.1 nm). However, it showed a good signal enhancement effect, and achieved a detection of 4-MBA as low as 1 × 10−11M, which was 8.7 times higher than that of the AuNRs substrate. In addition, the Au@Ag NRs substrate developed in this study was used for SRES detection of MG in crayfish; its detection limit was 1.58 × 10−9M. The developed Au@Ag NRs sensor had the advantages of stable SERS signal, uniform size and low cost, which provided a new tool for SERS signal enhancement and highly sensitive SERS detection method development.Keywords:Au@Ag nanorods substrate;surface-enhanced Raman scattering (SERS);malachite green
研究领域:
分析化学
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食品安全检测
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DOI
PubMed
高影响因子
MICROCHIMICA ACTA
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2023
·Vol. 191
·期 1
·1-12
·
IF 5.7
Liu Xinyu,Yu Yang,Xie Tianhua,Cao Zijin,Li Zhiyan,Li Yuejing,Gu Yingqiu,Han Caiqin,Yang Guohai,Qu Lulu
Monolayer g-C 3 N 4 -modified Au/Ag nanorods (g-C 3 N 4 /Au/Ag NRs) array is fabricated as a dual-function platform with high surface-enhanced Raman scattering (SERS) response and excellent photocatalytic degradation ability for bisphenol A (BPA) residues. FDTD simulation results of Au/Ag NRs proves that the electromagnetic field intensity is significantly enhanced at the gap of Ag NRs and Au NPs and the protrusion of Au NPs, which endows the arrays with excellent SERS activity. The arrays exhibit high sensitivity for rhodamine 6G (R6G) (LOD = 1.1 × 10 -11 mol/L) and high SERS enhancement (EF = 9.2 × 10 7 ). In addition, the g-C 3 N 4 /Au/Ag NRs could degrade ˃90% of BPA adsorbed on the substrate surface within 140 min under visible light irradiation, and maintains its SERS activity after repeated use for 4 times. The dual-function platform with high SERS response and excellent recycling capability is proved to be reliable and is very promising for monitoring of BPA residues in food. Graphical abstract
研究领域:
分析化学
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环境科学
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材料科学
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DOI
PubMed
高影响因子
Journal of Materials Chemistry C
·
2015
·Vol. 3
·期 23
·6035-6045
·
IF 4.696
Fan Zhang,Jian Zhu,Jian-Jun Li,Jun-Wu Zhao
The Ag coating-induced blue shift and enhancement of longitudinal plasmon of Au nanorods result in abundant and tunable optical absorptions in the visible region, which leads to the Au@Ag nanorod becoming a good candidate for colorimetric sensing. In this paper, we have reported an effective and simple approach for visualization detection of alpha-fetoprotein (AFP) based on Au@Ag core–shell nanorods. The AFP concentration-dependent colloid color of Au@Ag core–shell nanorods could change from green to gray, olivine to brown, and even blue to violet to pink, which are more varied color changes compared with the traditional red to blue color change. Besides, as the Ag shell thickness is increased, a dip was observed, which is located between two strong absorption peaks. The change of the dip is proposed as a new biosensor parameter for biomolecule detection based on absorption spectra. AFP concentration detection could be realized according to the change of the position and intensity of the dip, which has not been reported in the biomolecule detection field so far. Au@Ag core–shell nanorods with a small aspect ratio of inner Au nanorods are more suitable for direct read-out visualization, with a color change from blue to violet to pink. From the point of view of spectra analysis, Au@Ag core–shell nanorods with a greater aspect ratio of inner Au nanorods show higher spectral sensitivity. Furthermore, it is found that non-centrifuged Au@Ag core–shell nanorods are preferentially assembled in a side-by-side fashion with the addition of AFP, which will provide new approaches for other kinds of nanorods in controllable assembly fashions.
研究领域:
纳米技术
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医学诊断
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光学传感
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DOI
高影响因子
COLLOIDS AND SURFACES B-BIOINTERFACES
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2023
·
IF 5.8
Xinyu Cui,Minghui Li,Lei Tong,Miaojing Li,Xuefeng Tang,Xiaojun Han
Chemodynamic therapy (CDT) is based on the endogenous generation of cytotoxic hydroxyl free radicals (·OH) with high specificity and selectivity between cancer and normal cells. However, its efficacy is often limited by the relatively deficient catalytic activity of nanozymes in the tumor microenvironment (TME). Therefore, the combination of CDT with other strategy to realize synergistic therapy is necessary. Herein, a versatile plasmonic Au/Ag nanorods (abbreviated as Au/Ag NRs) via anisotropic Ag overgrowth on Au nanobipyramids was rationally devised to achieve synergistic nanozyme catalytic therapy and near infrared II (NIR-II) light induced photothermal therapy (PTT) with the guidance of computed tomography (CT) imaging. As TME contains high concentrations of H + and H 2 O 2 , Au/Ag NRs exhibited peroxidase (POD) activity to catalyze H 2 O 2 to produce ·OH, inducing cancer cell death. Meanwhile, Au/Ag NRs showed a preeminent NIR-II photothermal effect. More importantly, the enhanced ·OH generation by in-situ heating up resulting from PTT could conversely inhibit the expression of heat shock proteins (HSPs) to abate their resistance to PTT, realizing self-augmented synergistic effect. The NIR-II photothermally enhanced nanozyme catalytic cancer therapy validly inhibited the cancer proliferation, as demonstrated via both cell and animal assays. Moreover, ideal high-contrast CT imaging was realized, owing to the X-ray attenuation capability of elemental Au. The multifunctional Au/Ag NRs hold potential in oncotherapy with imaging capability, high efficiency and low side effects.
研究领域:
癌症治疗
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纳米技术
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光热治疗
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纳米酶
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成像技术
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DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）