Scientific Reports
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2018
·Vol. 8
·期 1
·1-9
·
IF 4.122
Li Aoqi,Duan Wanyi,Liu Jianming,Zhuo Kelei,Chen Yujuan,Wang Jianji
Deep eutectic solvents (DESs), called a new generation of green solvents, have broad applied in synthesis of nanomaterials due to their remarkable physicochemical properties. In this work, we used a unique strategy (adding moderate water (10%) to DES) to effectively prepare nanomaterials. Flower-like AuPt alloy nanoparticles were successfully synthesized using one-step electrochemical reduction method at a low potential of −0.30 V ( vs . Pt) and a low temperature of 30 °C. In this process, the DES acted as solvent and shape-directing agent. More importantly, we used the electrode modified with the as-prepared nanomaterials as the anode to the electrochemical oxidation synthesis. The glassy carbon electrode modified with the AuPt nanoflowers was directly employed to the electro-oxidation of xanthene (XT) to xanthone (XO) under a constant low potential of 0.80 V ( vs . Ag/AgCl) and room temperature, with a high yield of XO. Moreover, the synthesis process was milder and more environment-friendly than conventional organic syntheses. This new strategy would have a promising application in electroorganic synthesis fields.
研究领域:
材料科学
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电化学
·
绿色化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
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2016
·
IF 5.267
Xiangcun Li,Wenji Zheng,Bo Chen,Le Wang,Gaohong He
In this work, for the first time, AuPt alloy yolk@shell hollow nanoparticles (NPs) were constructed and simultaneously embedded into hollow interiors of a mesoporous silica microsphere based on a rapid aerosol process (AuPt@SiO2). Resin nanospheres were utilized both as a hard template to create hollow interiors inside the mesoporous silica microspheres and as carriers to transport pregrown metal nanocrystals, AuPt alloy clusters, into the microspheres. Calcination removes the resin nanospheres and causes metal nanocrystals to embed into the hollow interiors of the silica microspheres. Due to the unique yolk@shell hollow structure of the AuPt nanoalloy, ordered mesopores (67 nm) in the silica support, the synergetic effect between the AuPt alloy and the high surface area and pore volume of the microspheres, the AuPt@SiO2 spheres showed an excellent catalytic performance for styrene epoxidation with the conversion and selectivity of 85% and 87%, respectively. Notably, the novel catalyst showed a stable catalytic performance after five cycles of usage, suggesting the possible practical applications of the AuPt nanoalloy catalyst. In addition, the catalyst also exhibited a higher activity than the commercial Pt/C catalyst for the reduction reaction of 4-nitrophenol. The approach reported in this study could potentially be used to simplify the fabrication process of yolk@shell or hollow metal nanospheres, facilitating encapsulation of monometallic and multimetallic metal nanocrystals with various nanostructures and compositions into porous supports and thus guiding the design of catalysts with a special structure and high-performance.
研究领域:
材料科学
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催化化学
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产品关联
DOI
高影响因子
ANALYTICA CHIMICA ACTA
·
2021
·
IF 6.558
Kaicha Chen,Hongli Zhao,Zhenxing Wang,Minbo Lan
The detection of circulating tumor DNA (ctDNA) has increasingly received a great deal of attention considering its significance in cancer diagnosis. And the signal amplification plays an important role in the development of sensitive ctDNA biosensors . Herein, the nanocomposites (denoted as HAC-AuPt), integrating from high-active carbon (HAC) and AuPt alloy nanoparticles , were synthesized and subsequently used as a signal amplification label to fabricate a sandwich-type ctDNA electrochemical biosensor. Characterizations demonstrated that HAC presents uniform size distribution and AuPt alloy nanoparticles were successfully loaded on HAC. The current response could be amplified to a great extent by the resultant HAC-AuPt due to its excellent electrochemical property. The nanocomposites were further bounded with DNA signal probes (SPs) via Au-S or Pt-S assembly to form SPs-label. After the capture probes (CPs) were immobilized on the electrode surface, the target DNA (tDNA) and SPs-label were stepwise incubated on the CPs-modified electrode, thus forming a sandwich-type structure. By monitoring the catalytic signal of HAC-AuPt towards the reduction process of H 2 O 2 , this biosensor provided a wide linear range of 10 −8 mol/L - 10 −16 mol/L with a low detection limit of 3.6 × 10 −17 mol/L (S/N = 3) for the detection of the tDNA. Furthermore, obvious differences in response signals among different DNAs were observed benefitting from the excellent selectivity of the biosensor. Besides, the long-term stability, reproducibility, and recovery rate were proved to be outstanding. These results indicate that the established biosensor holds a potential application in the clinical diagnosis of ctDNA.
研究领域:
生物医学工程
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癌症诊断
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纳米技术
✓ 已验证
DOI
PubMed
高影响因子
SENSORS
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2016
·Vol. 16
·期 11
·1851
·
IF 2.033
Zongya Zhao,Ruxue Gong,Liang Zheng,Jue Wang
In order to reduce the impedance and improve in vivo neural recording performance of our developed Michigan type silicon electrodes, rough-surfaced AuPt alloy nanoparticles with nanoporosity were deposited on gold microelectrode sites through electro-co-deposition of Au-Pt-Cu alloy nanoparticles, followed by chemical dealloying Cu. The AuPt alloy nanoparticles modified gold microelectrode sites were characterized by scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and in vivo neural recording experiment. The SEM images showed that the prepared AuPt alloy nanoparticles exhibited cauliflower-like shapes and possessed very rough surfaces with many different sizes of pores. Average impedance of rough-surfaced AuPt alloy nanoparticles modified sites was 0.23 MΩ at 1 kHz, which was only 4.7% of that of bare gold microelectrode sites (4.9 MΩ), and corresponding in vitro background noise in the range of 1 Hz to 7500 Hz decreased to 7.5μVrmsfrom 34.1μVrmsat bare gold microelectrode sites. Spontaneous spike signal recording was used to evaluate in vivo neural recording performance of modified microelectrode sites, and results showed that rough-surfaced AuPt alloy nanoparticles modified microelectrode sites exhibited higher average spike signal-to-noise ratio (SNR) of 4.8 in lateral globus pallidus (GPe) due to lower background noise compared to control microelectrodes. Electro-co-deposition of Au-Pt-Cu alloy nanoparticles combined with chemical dealloying Cu was a convenient way for increasing the effective surface area of microelectrode sites, which could reduce electrode impedance and improve the quality of in vivo spike signal recording.Keywords:rough-surfaced AuPt alloy nanoparticles;in vivo neural recording;electro-co-deposition;microelectrode arrays
研究领域:
神经科学
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生物医学工程
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DOI
PubMed
高影响因子
ELECTROCHIMICA ACTA
·
2017
·
IF 4.798
Wen Wu,Zhenghua Tang,Kai Wang,Zhen Liu,Ligui Li,Shaowei Chen
Peptide driven metallic nanomaterials fabrication under mild conditions has become a significant research thrust recently, thanks to its capability to generate multifunctional materials with tunable electronic and catalytic properties. Herein, peptide Z1 is employed to fabricate a series of AuPt alloyed nanoparticles with different Au-to-Pt ratios. The morphology is examined by electron microscopic techniques, and well-defined peanut-shape is observed for Au 33 Pt 67 while spherical particles are obtained for the other samples. The AuPt alloys demonstrate effective electrocatalytic activity toward both oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) and Au 33 Pt 67 exhibits the best bifunctional electrocatalytic performance. Its ORR activity is superior than commercial Pt/C in alkaline media, verified by the positive onset potential (+1.02 V vs. RHE) and large diffusion-limited current density, while its HER activity is comparable with Pt/C, evidenced by the small overpotential at 10 mA cm −2 (−171 mV vs. RHE) and low Tafel slope. Moreover, Au 33 Pt 67 exhibits markedly higher long-term durability than Pt/C for both ORR and HER. The excellent activity and stability for ORR and HER are ascribed to Au alloying Pt induced synergistic effects. The results highlight the advantages of using peptide to fabricate bi-functional or multiple functional electrocatalysts with desirable activity and robust stability.
研究领域:
材料科学
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电化学
·
生物纳米技术
✓ 已验证
产品关联
DOI
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2018
·
IF 8.173
Wei Xu,Zhen Qin,Yutong Hao,Qiang He,Shuai Chen,Zhongshuang Zhang,Dan Peng,Haiyan Wen,Jun Chen,Jingfu Qiu,Chaorui Li
In this work, hollow nanobox metal-organic framework (HNM) nanocomposites were synthesised and utilised for the first time in a signal decreased electrochemical immunosensor for the ultrasensitive quantitative determination of lymphocyte activation gene-3 (LAG-3) protein, which is a newly discovered biomarker. With the aid of signal materials, namely, SiO 2 -tagged anti-LAG-3 antibody (SiO 2 -Ab 2 ) and the biotin-streptavidin system, the sensor can achieve signal amplification . Encapsulation of tin dioxide-functionalised reduced graphene oxide (rGO-SnO 2 ) and gold and platinum alloys (AuPt alloys) onto the surface of hollow nanobox metal-organic frameworks (MOFs) was performed to prepare rGO-SnO 2 /hollow nanobox-MOFs/AuPt alloys (rGO-SnO 2 /HNMs/AuPt) as the matrix. SiO 2 -Ab 2 , which is used as the signal-decreased label, can be utilised to enhance the distinction of the electrochemical signal after the specific recognition between antibodies and antigens, owing to its large steric hindrance property. In this sensor, this proposed sandwich immunosensor can achieve a high sensitivity, especially in the presence of low concentrations of the LAG-3 protein. Under optimal conditions, this sandwich-designed immunosensor exhibited a sensitive detection of the LAG-3 protein from concentrations of 0.01 ng mL −1 to 1 μg mL −1 , with a lower detection limit of 1.1 pg mL −1 (based on 3σ). We proposed that this ultrasensitive biosensor can be utilised for the detection of the LAG-3 protein in early clinical tumour diagnosis.
研究领域:
生物传感器
·
分析化学
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材料科学
·
肿瘤学
✓ 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）