Nanomaterials
·
2018
·Vol. 8
·期 11
·872
·
IF 3.504
Furu Zhong,Zhaofeng Wu,Jixi Guo,Dianzeng Jia
Picric acid (PA) is an organic substance widely used in industry and military, which poses a great threat to the environment and security due to its unstable, toxic, and explosive properties. Trace detection of PA is also a challenging task because of its highly acidic and anionic character. In this work, silver nanoparticles (AgNPs)-decorated porous silicon photonic crystals (PS PCs) were controllably prepared as surface-enhanced Raman scattering (SERS) substrates using the immersion plating solution. PA and Rhodamine 6G dye (R6G) were used as the analyte to explore the detection performance. As compared with single layer porous silicon, the enhancement factor of PS PCs substrates is increased to 3.58 times at the concentration of 10−6mol/L (R6G). This additional enhancement was greatly beneficial to the trace-amount-detection of target molecules. Under the optimized assay condition, the platform shows a distinguished sensitivity with the limit of detection of PA as low as 10−8mol/L, the linear range from 10−4to 10−7mol/L, and a decent reproducibility with a relative standard deviation (RSD) of ca. 8%. These results show that the AgNPs-modified PS PCs substrates could also find further applications in biomedical and environmental sensing.Keywords:porous silicon photonic crystals;Ag nanoparticles;optical properties;SERS.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
·
2018
·
IF 6.042
Zhiyong Guo,Yaru Jia,Xinxin Song,Jing Lu,Xuefei Lu,Baoqing Liu,Jiaojiao Han,Youju Huang,Jiawei Zhang,Tao Chen
Conventional methods for the detection of Vibrio parahemolyticus (VP) usually need tedious, labor-intensive processes, and have low sensitivity, which further limits their practical applications. Herein, we developed a simple and efficient colorimetry and surface-enhanced Raman scattering (SERS) dual-mode immunosensor for sensitive detection of VP, by employing giant Au vesicles with anchored tiny gold nanowires (AuNW) as a smart probe. Due to the larger specific surface and special hollow structure of giant Au vesicles, silver staining would easily lead to vivid color change for colorimetric analysis and further amplify SERS signals. The t-test was further used to determine if two sets of data from colorimetry and SERS were significantly different from each other. The result shows that there was no significant difference between data from the two methods. Two sets of data can mutually validate each other and avoid false positive and negative detection. The designed colorimetry–SERS dual-mode sensor would be very promising in various applications such as food safety inspection, personal healthcare, and on-site environmental monitoring.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Nano Materials
·
2018
·
IF 0
Xingying Zhang,Yalun Mo,Ben Liu,Chenglong Hu,Shaoyun Chen,Hong Shi,Jian Chen
The Ag-nanosheets (i.e., AgNST)-grafted carbon-fenced conductive Ag nanowires with 3D scale-like nanostructure was successfully fabricated through a direct chemical reduction method, where the carbon shell was first carbonized onto the suface of Ag nanowires to form an Ag nanowires@carbon (i.e., AgNWs@C) framework, and then the citrate acid which absorbed on the prefabricated AgNWs@C@Ag seeds framework directed Ag ions to be Ag nanosheets to self-assemble into 3D scale-like nanostructures (i.e., AgNWs@C@AgNST). The fabricated nanostructure displayed the sensitive and reproducible surface-enhanced Raman scattering (SERS) responses. The SERS detection for the probing molecule (rhodamine 6G, R6G) with concentration as low as 10–12 mol/L was obtained in a reproducible way, and the average enhancement factor was about 2.33 × 105, which was calculated from the band of 610 cm–1 in the SERS spectrum. It was caused by Ag nanosheets with high density providing abundant “hot spots” to enhance the SERS detection. Besides, the potential SERS detection of glucose molecules in the micromolar range was also reported.
✓ 已验证
产品关联
DOI
CRYSTENGCOMM
·
2019
·Vol. 21
·期 24
·3709-3720
·
IF 3.382
Shanshan Li,Qi Wang,Xinyu Song,Yuxiang Bu
Semiconductor-based materials as SERS-active substrates have gained significant attention because of their superior properties. However, to date, only few studies have been reported on the SERS performance of substrates fabricated using CdS-based composites. In this study, hollow sphere-like Ag/CdS nanocomposites (NCs) with multi-hot spots were successfully synthesized via a room-temperature solution route without the addition of surfactant. Especially, note that in our strategy, the cadmium ions in an aqueous solution originating from the self-template core dissolved with acid were retrieved and recycled via a simple approach, avoiding the wastage of resources and environmental problems. Moreover, a strong electromagnetic enhancement between two neighboring Ag nanoparticles (NPs) on the CdS sphere-like surface could be achieved by conveniently adjusting the amount of the AgNO3 reagent. Note that the as-prepared substrate with low loading of Ag presented superior SERS performance with the ultralow limit of detection of 10−12 mol L−1 for R6G and CV, much higher than that of many recently reported composite substrates. These significantly enhanced SERS effects are attributed to the combination of several contributions, including plasmonic coupling between Ag NPs, synergistic charge-transfer resonances in the Ag/CdS/dye molecule system, and cadmium defect-induced electrostatic forces. As a consequence, the present study not only develops a convenient, environmentally friendly approach for the fabrication of noble/CdS composites but also indicates the promising potential application of these composites as ideal SERS substrates in the detection of organic pollutants.
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2017
·
IF 5.401
De Zhang,Pei Liang,Zhi Yu,Jie Huang,Dejiang Ni,Haibo Shu,Qian-min Dong
In this paper, the flower-shaped silver nanoparticle was used as substrate to investigate the SERS effect of pesticide molecules under different treatment conditions. Due to the variation of molecular structure and molecular interactions with pH value and solvent type, the combination mode of molecules and metal surface and electron transfer also changes, resulting in different SERS effects with a certain regularity. It was demonstrated that the optimum pH values for test conditions are in the range of 6.66–11.11 due to the auxiliary of H + ions and undestroyed complete functional groups of ethion. Meanwhile, the ethion in the acetone was the best in the three solvents (ultrapure water, absolute ethanol and acetone). Under optimal conditions, ethion can be detected with a minimum detectable concentration of 10 −10 M. The regression model obtained through principal component analysis (PCA) can be used for rapid and precise detection of the concentration of ethion, suggesting the importance of condition optimization for SERS test. Therefore, the solvent environment can be effectively improved to promote non-resonance enhancement of chemical bonding between adsorbate and metal substrate and resonance enhancement of light-induced charge transfer in molecular-metal system by excitation light. The solvent environment has significant effect on the SERS sensor from chemical enhancement.
✓ 已验证
产品关联
DOI
高影响因子
FOOD CONTROL
·
2024
·
IF 5.6
Yifei He,Jinxiang Wei,Lili Zhang,Yu Xia,Zhouping Wang,Junsong Yang
In this study, a dual-mode SERS-fluorescent aptasensor based on a DNA walker was developed for Shigella flexneri ( S . flexneri ). Fe@SiO2@QDs were connected with H1 and the walking chain (hybrid strands of aptamer and cDNA) to fabricate fluorescent probes, and Ag R6G @SiO 2 were connected with H2 to fabricate SERS tags. Aptamer (Kd = 42.6 ± 3.16 nM) selective binding of S . flexneri , left the walking chain. The Zn 2+ -specific DNAzyme in the cDNA was exposed thus driving the DNA walker. The sequence on H1 containing BHQ3 was cleaved from fluorescent probes to restore the fluorescence. The remaining H1 sequence could bind to the H2 to generate Raman signals. The detection limit of the fluorescence signal was 11 CFU/mL, and the Raman signal was 3 CFU/mL. In addition, the aptasensor was successfully applied to the detection of actual samples with recovery ranges of 98.35–107.27% and 97.57–105.91% for the fluorescence and SERS methods, respectively.
✓ 已验证
产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2024
·
IF 4.9
Dingkun Yang,Yu Lei,Zhou Fan,Weigen Chen,Fu Wan
Surface-enhanced Raman scattering (SERS), functioning as a highly sensitive trace detection tool, has gained popularity as an analytical technique and is extensively employed in diverse domains such as electrical engineering. In this paper, the exploration is conducted regarding the application of surface-enhancement technology in the quantitative detection of the aging characteristics of transformer oil-paper insulation. Flower-like silver nanoparticles (AgNPs) were deposited in situ on a copper foil coated with porous graphene, thereby fabricating a Cu-graphene (porous)-AgNPs surface-enhanced substrate. This substrate effectively prevented the oxidation of nanoparticles while maintaining the SERS activity. By creating apertures in graphene, the adsorption capability of the substrate for organic small molecules like furfural was enhanced, and the size of silver nanoparticles was optimized to achieve better detection outcomes. The performance of the substrate was evaluated using R6G as the probe molecule, and the findings indicated that the substrate exhibited excellent sensitivity, uniformity (RSD values are below 10 %), and antioxidant properties (after 30 days, the peak strength decreased by 8.23 %). When this substrate was utilized for the detection of transformer aging characteristics, the detection limits for furfural, acetone, and methanol reached 0.04 mg/L, 0.18 mg/L, and 0.18 mg/L respectively, fulfilling the analytical requirements of oil-immersed transformers. This research holds significant importance in guaranteeing the stable operation of the power supply system and the smooth development of the national economy.
✓ 已验证
产品关联
DOI
高影响因子
FOOD CONTROL
·
2016
·
IF 3.388
Ruoping Li,Guanghong Yang,Jingliang Yang,Junhe Han,Junhui Liu,Mingju Huang
A simple and rapid method to detect melamine in liquid milk by Surface-enhanced Raman Scattering (SERS) technique was presented. The pretreatment procedure of milk samples only contains hydrochloric acid treatment and twice centrifugation. In order to reduce the distortion about the Raman signals originating from charge transfer and electronic tunnelling effect, SiO 2 shell-isolated gold nanoparticles (Au@SiO 2 NPs) instead of Au NPs were employed to enhance signal intensity. Aggregation occurs when the Au@SiO 2 NPs colloid is mixed with the melamine solution or the treated milk containing melamine. Different from aggregated Au NPs, these aggregated Au@SiO 2 NPs on Cu substrate can undistortedly enhance the Raman signals of melamine using surface plasma effect. Quantitative analysis was tried and the results showed a good linearity (R 2 ≈ 0.99) when the melamine concentration was between 0.5 mgL −1 and 5 mgL −1 . The detection sensitivity satisfies the requirement of the Codex Alimentarius Commission and this method can be practically used for melamine detection in milk.
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2016
·Vol. 8
·期 11
·5920-5927
·
IF 7.76
Chaofan Sui,Kaige Wang,Shuang Wang,Junying Ren,Xiaohong Bai,Jintao Bai
Most of SERS applications are constricted by heterogeneous hotspots and aggregates of nanostructure, which result in low sensitivity and poor reproducibility of characteristic signals. This work intends to introduce SERS properties of a type of SERS-active substrate, Au-CuCl2-AAO, which is innovatively developed on a porous anodic alumina oxide (AAO) template. Spectral measuring results of Rhodamine 6G (R6G) on this substrate optimized by controlling morphology and gold thickness showed that enhancement factor (2.30 × 107) and detection limit (10−10 M) were both improved and represented better performance than its template AAO. Homogenous hot spots across the region of interest were achieved by scanning SERS intensity distribution for the band at 1505 cm−1 in 5 × 5 μm2 area. Furthermore, the promising SERS activity of the flower-patterned substrate was theoretically explained through simulation of the electromagnetic field distribution. In addition, this SERS substrate is proposed for applications within the field of chemical and biochemical analyses.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF NANOPARTICLE RESEARCH
·
2016
·Vol. 18
·期 1
·1-13
·
IF 2.101
Ma Shuzhen,Cai Qian,Lu Kailing,Liao Fan,Shao Mingwang
Abstract The bi-functional Au/FeS (Au/Co 3 O 4 ) composite was fabricated by in situ reducing Au nanoparticles onto the surface of FeS (Co 3 O 4 ). The as-prepared FeS possessed a multi-structure composed of plenty of nanoplates, which were coated by Au nanoparticles with an average size of ~47.5 nm. While the Co 3 O 4 showed a thin hexagonal sheet containing Au nanoparticles on its surface with an average size of ~79.0 nm. Both the as-prepared Au/FeS and Au/Co 3 O 4 composites exhibited excellent SERS performance, capable of enhancing the Raman signals of R6G molecules with the enhancement factor up to 1.81 × 10 6 and 7.60 × 10 4 , respectively. Moreover, Au/FeS (Au/Co 3 O 4 ) composite also has been verified to have intrinsic peroxidase-like activity, which could decompose H 2 O 2 into hydroxyl radicals and then degrade organic pollutants into small molecules. Therefore, SERS can be used to real-time and in situ monitoring the degradation process of R6G molecules, employing the Au/FeS (Au/Co 3 O 4 ) composite both as SERS substrate and catalyst. Graphical abstract SERS was used to real-time and in situ monitoring the degradation of R6G, employing the Au/FeS and Au/Co 3 O 4 composites both as SERS substrates and catalysts.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2015
·Vol. 3
·期 22
·5709-5714
·
IF 4.696
Jingjing Wang,Guotao Duan,Guangqiang Liu,Yue Li,Lei Xu,Weiping Cai
A simple and universal method, based on a polypyrrole (PPy) through-pore template induced by the colloidal monolayer, is developed to fabricate the gold and silver hierarchically micro/nanostructured arrays with a hexagonally packed pattern and controllable morphologies through electrochemical deposition. Using the polystyrene colloidal monolayer as the first template, a hexagonally packed PPy through-pore thin film was electrodeposited and used as a secondary template to adjust the interface electroconductivity, further to control the localized electrocrystallization process. Final electrodeposition under appropriate conditions can easily lead to several kinds of metal periodic arrays. These hierarchically micro/nanostructured arrays can be used as surface-enhanced Raman scattering (SERS) active substrates. Before use, a certain thickness of the gold layer was ion-sputtered onto the periodic arrays to eliminate the interference from PPy film and enhance the substrate SERS activity. Such a gold-covering strategy can also provide an effective method to clean the impurity-adsorbed SERS substrate, which is quite important in SERS-based applications.
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2014
·
IF 5.9
Hui Chen,Zhuyuan Wang,Shenfei Zong,Lei Wu,Peng Chen,Dan Zhu,Chunlei Wang,Shuhong Xu,Yiping Cui
A redox-responsive drug carrier based on nanoscale graphene oxide (NGO) loaded with Ag nanoparticles, whose intracellular release behavior can be investigated by SERS-fluorescence combined spectroscopy, is presented. In this demonstrated drug carrier, to make the carrier integrated with the redox responsive property, we utilized disulfide linkages to load drug molecules to the surfaces of NGO directly, which can be cleaved by glutathione (GSH). Covalent drug loading and GSH-responsive release strategy can reduce the influence of the surface diffusion barriers introduced by multifunctionalization. Interestingly, the intracellular real-time drug release dynamics can be monitored by the combined SERS-fluorescence signals of the drugs, while the distribution of the drug carrier can simultaneously be tracked by the intrinsic SERS signals of NGO in the whole process. Our results show that upon the internalization of doxorubicin (DOX)-loaded nanocarriers into living cells, DOX was efficiently released under a GSH regulated reducing environment. Because tumor cells generally exhibit a higher concentration of GSH than normal ones, this drug carrier should have potential in the field of tumor therapy.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）