SENSORS AND ACTUATORS B-CHEMICAL
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2016
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IF 4.758
Jian Zhu,Jing-Fei Wang,Jian-Jun Li,Jun-Wu Zhao
Gold-silver bimetallic fluorescence quenching nanoprobe has been synthesized based on the gold triangular nanoplate with silver coating. In order to guarantee the specificity of the probe, surface modifications of the triangular nanoplates including carboxyl replacement, carboxyl activation and antibody connection have been carried out. The fluorescence spectral study indicates that the fluorescence intensity of carcinoembryonic antigen (CEA) could be effectively quenched by the silver coated-gold triangular nanoprobe. And the fluorescence quenching ability could be improved by optimizing the interaction time and amount of binding anti-CEA to modified nanoprobe, and the interaction time of binding CEA to anti-CEA. By using this sensing method, the CEA could be detected with an ultra low detection limit of 10 pg/mL, and the linear range spans a scope from 20 to 200 pg/mL. Interference experiment results show that the influence from the interfering proteins could be neglected in the detection procedure. And the CEA could be specifically detected by using this bimetallic triangular nanoplate probe.
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高影响因子
BIOSENSORS & BIOELECTRONICS
·
2016
·
IF 7.476
Yayun Yang,Huan Zhang,Chusen Huang,Dapeng Yang,Nengqing Jia
Clenbuterol (CLB), a kind of β 2 -adrenergic agonists, could disrupt cardiovascular and central nervous system. In this work, a new electrochemical non-enzyme sensor for detecting Clenbuterol (CLB) was fabricated based on MoS 2 -Au-PEI-hemin layered nanocomposites . The two-dimensional (2-D) MoS 2 nanosheets were first in-situ assembled with Au nanoparticles , and polyethylenimine (PEI), then hemin molecules were immobilized onto the MoS 2 -Au-PEI film-modified glassy carbon electrode (GCE) via amide bond. Scanning electron microscopy (SEM) and Zeta potential measurements were employed to characterize the MoS 2 -based nanomaterials . Cyclic voltammetry (CV) was used to investigate electrochemical activity of the immobilized hemin on the modified electrode . Upon the optimum conditions, the proposed electrochemical sensor showed an excellent response for CLB including a wide linear ranging from 10 ng/mL to 2 μg/mL and a detection limit (LOD) of 1.92 ng/mL CLB (S/N=3) with favorable reproducibility and stability. Furthermore, this presented method could be feasible for determining CLB in the real pork samples.
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PubMed
高影响因子
ANALYST
·
2016
·Vol. 141
·期 11
·3337-3342
·
IF 4.033
Shanshan Wang,Zhangkun Liu,Yuxiu Zou,Xiaofang Lai,Ding Ding,Long Chen,Liqin Zhang,Yuan Wu,Zhuo Chen,Weihong Tan
Elucidating the endocytosis and metabolism of nanoparticles in cells could improve the diagnostic sensitivity and therapeutic efficiency. In this work, we explore the cellular uptake mechanism of a biocompatible nanocrystal nanostructure, graphene-isolated-Au-nanocrystals (GIANs), by monitoring the intrinsic Raman and two-photon luminescence signals of GIANs in live cells. Aptamers functionalized on the GIAN nanostructure through simple, but strong, π–π interactions entered the cells through a clathrin-dependent pathway, while unmodified GIANs mainly entered the cells through a caveolae-mediated endocytosis pathway. Thus, it can be concluded that the mechanism of cellular uptake in these graphene-isolated-Au-nanocrystal nanostructures is determined by the presence or absence of aptamer modification.
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高影响因子
Journal of Materials Chemistry A
·
2016
·Vol. 4
·期 32
·12630-12637
·
IF 8.262
Jianjun Ding,Xiangyang Li,Lin Chen,Xian Zhang,Song Sun,Jun Bao,Chen Gao,Xingyou Tian
Au–Pt/CaIn2S4 composites were synthesized for the first time using the photoreduction method by which bimetallic Au–Pt alloy nanoparticles were in situ site-selectively photoreduced on the edges of monoclinic CaIn2S4 nanosteps. The Au–Pt alloy nanoparticles as cocatalysts can spatially separate the oxidation and reduction sites and effectively enhance the photocatalytic hydrogen activity of CaIn2S4 under visible light irradiation. When introducing 0.5 wt% Au–Pt alloy nanoparticles, the rate of hydrogen production could reach 107.6 μmol h−1, which was higher than that of CaIn2S4, Au/CaIn2S4 and Pt/CaIn2S4 by a factor of 18.3, 2.37 and 2.4, respectively. The enhanced photocatalytic activity for hydrogen production could be attributed to the low recombination efficiency of the photogenerated charges and surface-plasmon-resonance-induced effect of Au nanoparticles.
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高影响因子
BIOSENSORS & BIOELECTRONICS
·
2016
·
IF 7.476
Hang Ao,Zhaosheng Qian,Yuyu Zhu,Meizhi Zhao,Cong Tang,Yuanyuan Huang,Hui Feng,Aijun Wang
Due to the vital role of tyrosinase in melanin biosynthesis and its function as an important biomarker for melanoma cancer, highly sensitive detection of its activity using biocompatible materials is in urgent demand. Herein we report a convenient and highly sensitive fluorometric biosensor for tyrosinase activity detection based on biocompatible dopamine-functionalized Au/Ag nanoclusters (Dopa-Au/Ag NCs). Dopamine with redox property was covalently linked to Au/Ag NCs surface and formed a Dopa-Au/Ag NCs bioconjugate with strong blue fluorescence. Dopamine is readily oxidized by molecular oxygen under the catalysis of tyrosinase. After dopamine is transformed to o -dopaquinone, an intraparticle photoinduced election transfer (PET) process occurs between Au/Ag NCs and o -dopaquinone moiety, leading to the fluorescence quenching of the Dopa-Au/Ag NCs bioconjugate. Thus, this biosensor was utilized for sensitive and selective detection of tyrosinase in terms of the relationship between fluorescence quenching efficiency and tyrosinase activity. This study discovers that Au/Ag NCs and dopaquinone can serve as a good electron acceptor and donor pair which results in an efficient intraparticle photoinduced electron transfer process, and also provides another alternative way for tyrosinase activity monitoring.
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高影响因子
BIOSENSORS & BIOELECTRONICS
·
2016
·
IF 7.476
Long Wu,Xiaoyan Xiao,Kun Chen,Wenmin Yin,Qin Li,Pan Wang,Zhicheng Lu,Jing Ma,Heyou Han
Abstrcact Highly sensitive and selective detection of specific DNA sequences is of great importance in clinical diagnosis, environmental and food monitoring, but it still remains challenges to develop a facile method for real sample detection in aqueous solution. Here, a simple and recyclable surface enhanced Raman scattering (SERS) sensor was constructed for Bacillus thuringiensis (Bt) special gene fragment detection by Fe 3 O 4 magnetic beads (MBs) and Au–Ag core-shell nanorods (Au@Ag NRs). A hairpin DNA with sulfhydryl and biotin was attached to Au@Ag NRs as indicator, and MBs with streptavidin (SA) were acted as the capture probe. On the basis of the biotin–SA specific interaction, target sequences were first hybridized with the hairpin DNA and exposed the biotin. Subsequently, the Au@Ag NRs were captured by the streptavidin modified MBs, which reduced the suspended NRs and led to the change of Raman intensity . Under the optimal conditions, the SERS intensity revealed a good linearity with Bt transgene fragment ranging from 0.1 pM to 1 nM with a detection limit of 0.14 pM (S/N=3). To demonstrate the specificity of the strategy, the single-base mismatch in DNA was discussed in the SERS assay. The results showed that the sensitivity and accuracy of the proposed method was acceptable in DNA detection, revealing a great potential in special gene detection.
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高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2016
·
IF 4.758
Ying Wang,Zhenting Zhao,Yongjiao Sun,Pengwei Li,Jianlong Ji,Yong Chen,Wendong Zhang,Jie Hu
Pristine tin dioxide (SnO 2 ) and Au-loaded SnO 2 composite nanoparticles were synthesized by a simple hydrothermal method. The phase structure, composition, and morphology of synthesized Au-loaded SnO 2 composite nanoparticles were comprehensively investigated. Furthermore, the gas sensing performance of the as-prepared pristine and Au-loaded SnO 2 gas sensors toward low concentration of hydrogen (H 2 ) were systematically evaluated. The results indicated that compared to the pristine SnO 2 gas sensor, the Au-loaded SnO 2 composite nanoparticles could not only significantly improve the gas sensing response, but also decrease the optimum working temperature. Moreover, the experimental results showed that the 4.0 at.% Au-loaded SnO 2 gas sensor exhibited the highest response (25) to 100 ppm H 2 at 250 °C, which was about five times higher than that of the pristine one. In addition, it also provided a rapid response/recovery time (1 s/3 s) and a low detection limit (1 ppb). Therefore, Au-loaded SnO 2 composite nanoparticles are more suited for hydrogen detection compared to pristine SnO 2 gas sensor.
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高影响因子
ACS Applied Materials & Interfaces
·
2017
·
IF 7.504
Peng Miao,Yuguo Tang,Lei Wang
Driven by the urgent need to detect trace heavy metal ions in various real water samples, this article demonstrates for the first time an electrochemical biosensor based on DNA modified Fe3O4@Au magnetic nanoparticles (NPs). Three DNA probes are designed to contain certain mismatched base pairs. One is thiolated and modified on the surface of Fe3O4@Au NPs (DNA 1). The other two probes (DNA 2 and 3) are labeled with two independent electrochemical species. Stable structures of cytosine–Ag+–cytosine and thymine–Hg2+–thymine formed in the presence of Ag+ and Hg2+ can assist the hybridization of DNA 1/DNA 2 and DNA 1/DNA 3, which locate corresponding electrochemical species onto the surface of the magnetic NPs. The achieved nanocomposites are then used as selective electrochemical probes for the detection of heavy metal ions by recording the square wave voltammetry signals. Simultaneous detection of Ag+ and Hg2+ is demonstrated without significant interference, and their individual high sensitivities are fundamentally preserved, which meet the requirements of U.S. Environmental Protection Agency (USEPA). Furthermore, the proposed method has been challenged by various real water samples. The results confirm the DNA modified magnetic NPs based sensing method may have potential applications for the monitoring of heavy metal ions in real sample analysis.
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高影响因子
OPTIK
·
2016
·
IF 0.742
Yong Wei,Yan-ying Zhu,Ming-li Wang
Recent studies have conclusively show that the surface-enhanced Raman spectroscopy (SERS) has been widely used for chemical and biomolecular sensing. In this work, a facile, low-cost, green and rapid method to detect the pesticide residues is presented by using Au nanoparticles/dragonfly wing (AuNPs/DW) arrays as SERS-active substrate. The AuNPs/DW substrate is prepared by decorating the AuNPs on the DW surface with a simple two-step method, meanwhile, the microstructure properties and SERS signal are characterized by the scanning electron microscopy (SEM) and confocal microprobe Raman system. The experimental results show that compared with the conventional Raman spectroscopy, the AuNPs/DW substrate can enhance the Raman signal dramatically due to the largescale nanosized protrusions on the DW surface. The detection limit for rhodamine 6G (R6G) could reach as low as 10 −8 M, which is important for the analysis of the most components and structures of samples. For the application of the three-dimensional AuNPs/DW, the micro-sample of thiram and carbaryl can also be detected quantitatively, and the detection limit both reach up to 10 −7 M. The above phenomenon indicate that three-dimensional nanostructure AuNPs/DW is a promising SERS substrate for the test of samples in low concentration. Hence, our study will provide an effective approach for the rapid, sensitive and stable trace detection of organic molecular species.
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高影响因子
TALANTA
·
2016
·
IF 4.035
Yuhong Liu,Linlin Zhao,Jin Zhang,Jinzha Zhang,Wenbo Zhao,Chun Mao
The work investigates a new fluorescence resonance energy transfer (FRET) system using NaEuF 4 nanoparticles (NPs) and [email protected] 2 S NPs as the energy donor–acceptor pair for the first time. The NaEuF 4 / [email protected] 2 S NPs-based FRET DNA sensor was constructed with NaEuF 4 NPs as the fluorescence (FL) donor and [email protected] 2 S core−shell NPs as FL acceptor. In order to find the matching energy acceptor, the amount of AgNO 3 and Na 2 S were controlled in the synthesis process to overlap the absorption spectrum of energy acceptor with the emission spectrum of energy donors. The sensitivity of FRET-based DNA sensor can be enhanced and the self-absorption of ligand as well as the background of signals can be decreased because of Eu 3+ which owns large Stokes shifts and narrow emission bands due to f–f electronic transitions of 4f shell. We obtained the efficient FRET system by studying suitable distance between the donor and acceptor. Then the FRET-based DNA sensor was used for the design of specific and sensitive detection of target DNA and the quenching efficiency (ΔFL/F 0 , ΔFL=F−F 0 ) of FL was logarithmically related to the concentration of the target DNA, ranging from 100 aM to 100 pM. We can realize an ultrasensitive detection of target DNA with a detection limit of 32 aM. This proposed method was feasible to analyse target DNA in real samples with satisfactory results.
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高影响因子
Results in Physics
·
2017
·
IF 0.946
Lang Yang,Feifei Jia,Bingqiao Yang,Shaoxian Song
The adsorption of gold cyanide complex ion (Au(CN) 2 − ) on graphene oxide-polyethylenimine hydrogel (GO/PEI hydrogel) from gold cyanidation has been studied to explore the possibility of the application of GO/PEI hydrogel in gold cyanidation process for extracting gold from ores. The adsorption was carried out in artificial Au(CN) 2 − aqueous solution with GO/PEI hydrogel as adsorbent. The experimental results, as well as IR, XPS and SEM−EDS, have shown that GO/PEI hydrogel exhibited a high adsorption capacity and a fast adsorption rate of Au(CN) 2 − , suggesting that GO/PEI hydrogel might be a good adsorbent for the recovery of Au(CN) 2 − . The adsorption of Au(CN) 2 − on GO/PEI hydrogel obeyed the Langmuir isotherm model and fitted well with the pseudo second order model. The good recovery of Au(CN) 2 − was largely related to the porous structure, large specific surface area, as well as the oxygenous functional groups on the surface of GO/PEI hydrogel.
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SENSORS AND ACTUATORS B-CHEMICAL
·
2017
·
IF 5.401
Chong Sun,Muhan Zhang,Qiqi Fei,Daoying Wang,Zhilan Sun,Zhiming Geng,Weimin Xu,Fang Liu
In this paper, a novel immunosensor was built for quantitative detection of heat shock protein 90 (HSP90) based on graphite-like carbon nitride nanosheets (g-C 3 N 4 NSs) hybridized with gold-F127 nanoparticles (g-C 3 N 4 -F127-Au NSs) modified electrode. The transmission electron microscope (TEM) was used to observe the structure and morphology of g-C 3 N 4 -F127-Au NSs. The successful preparation of g-C 3 N 4 -F127-Au NSs was characterized by UV–vis spectra, fourier transform infrared spectra (FTIR) and Raman spectra. Meanwhile, the electrochemical properties were measured by linear sweep voltammetric (LSV) and differential pulse voltammetry (DPV). Under the optimized conditions, the peak currents were linear with the concentration of HSP90 ranging from 3.5 μg/mL to 2.43 mg/mL. The linear regression equation was I (μA) = 10.31–10.05logc (R 2 = 0.9986, n = 9) with the detection limit of 2.67 μg/mL. Finally, the immunosensor exhibited good selectivity performance and provided a new approach for meat quality evaluation.
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高影响因子
危险品化学品经营许可证（带存储）