查找使用阿拉丁产品的科研文献

Electrochemical Sensor Based on Au NPs@NiPc-Cu MOFs Modified Electrode for the Rapid Detection of Luteolin

Wensi Xu,Xiansen He,Xiaokun Li,Suxiang Feng

In this study, a novel electrochemical sensor was designed to detect luteolin (Lu) with the composite of gold nanoparticles and nickel phthalocyanine-based 2D conductive metal-organic frameworks (Au NPs@NiPc-Cu MOFs) for the first time. The NiPc-Cu MOFs exhibit excellent conductivity, large specific surface area, and porous structure, which can accelerate the mass transfer process of target molecules. To further improve the sensitivity of the sensing platform, Au NPs with outstanding conductivity were introduced to the surface of NiPc-Cu MOFs to prepare Au NPs@NiPc-Cu MOFs. The synergistic effect of NiPc-Cu MOFs and Au NPs endows the sensor with excellent electrocatalytic performance and outstanding sensitivity. Under optimal conditions, the electrochemical sensor has a wide linear range (0.1–40 μM). Moreover, the prepared sensor possesses good stability and anti-interference ability. This method does not require complicated sample pretreatment, simple operation, and short detection time, which can provide a new method for the rapid detection of Lu.

Ultra-Small and Metabolizable Near-Infrared Au/Gd Nanoclusters for Targeted FL/MRI Imaging and Cancer Theranostics

Xiawei Dong,Jing Ye,Yihan Wang,Hongjie Xiong,Hui Jiang,Hongbing Lu,Xiaohui Liu,Xuemei Wang

Tumor accurate imaging can effectively guide tumor resection and accurate follow-up targeted therapy. The development of imaging-stable, safe, and metabolizable contrast agents is key to accurate tumor imaging. Herein, ultra-small and metabolizable dual-mode imaging probe Au/[email protected]NCs is rationally engineered by a simple hydrothermal method to achieve accurate FL/MRI imaging of tumors. The probes exhibit ultra-small size (2.5–3.0 nm), near-infrared fluorescence (690 nm), high quantum yield (4.4%), and a better T1nuclear magnetic signal compared to commercial MRI contrast agents. By modifying the folic acid (FA) molecules, the uptake and targeting of the probes are effectively improved, enabling specific fluorescence imaging of breast cancer. Au/[email protected]NCs with good biosafety were found to be excreted in the feces after imaging without affecting the normal physiological metabolism of mice. Intracellular reactive oxygen species (ROS) increased significantly after incubation of Au/[email protected]NCs with tumor cells under 660 nm laser irradiation, indicating that Au/[email protected]NCs can promote intracellular ROS production and effectively induce cell apoptosis. Thus, metabolizable Au/[email protected]NCs provide a potential candidate probe for multimodal imaging and tumor diagnosis in clinical basic research. Meanwhile, Au/[email protected]NCs mediated excessive intracellular production of ROS that could help promote tumor cell death.Keywords:Au/[email protected]NCs;dual-mode probe;FL/MRI imaging;reactive oxygen species (ROS);cancer theranostics

An aptamer-controlled Mn-Au nanozyme for H2O2-free and smartphone-assisted colorimetric detection of mercury ions

Ma Chen,Zhang Yida,Mu Shuai,Zhang Yuan,Wei Shuoyun,Li Quanfang,Ren Shufang

A novel Hg 2+ sensing strategy has been developed based on a Mn-Au hybrid nanozyme with prominent oxidase-like activity and an aptamer-controlled catalytic switching mechanism. First, a Mn-Au hybrid nanozyme (MnAuNPs) with a distinctive “fried-egg-like” core–shell morphology was synthesized, which exhibited remarkable oxidase-like activity and rapidly oxidized 3,3’,5,5’-tetramethylbenzidine (TMB) into the characteristic blue product (OxTMB) without H 2 O 2 . The Hg 2+ -specific aptamer can adsorb onto the surface of MnAuNPs through electrostatic and Mn-phosphate coordination interactions, which blocks the catalytic sites and markedly suppresses the oxidase-like activity. In the presence of Hg 2+ , the specific T-Hg 2+ -T coordination triggers the detachment of the aptamer from the MnAuNPs surface, thereby restoring oxidase-like activity and inducing distinct color and absorbance change. Accordingly, an effective colorimetric platform for Hg 2+ detection was developed, exhibiting a linear response over the range of 1.0–50 μM with a limit of detection (LOD) of 0.32 μM. In parallel, a paper-based smartphone-assisted sensing platform was developed, enabling on-site Hg 2+ detection in the range of 5.0–50 μM with LOD of 5.0 μM. Through the colorimetric and smartphone-assisted method, accurate quantification of Hg 2+ in the Yellow River water and wastewater samples were achieved with the results in good agreement with those obtained by ICP-OES. Overall, this work establishes a simple and portable H 2 O 2 -free colorimetric sensing strategy based on Hg 2+ -induced catalytic switching for environmental Hg 2+ monitoring. Graphical

Electrochemical aptamer sensor for highly sensitive detection of mercury ion with Au/Pt@carbon nanofiber-modified electrode

Hui Xie,Yanyan Niu,Ying Deng,Hui Cheng,Chengxiang Ruan,Guangjiu Li,Wei Sun

In this paper, an electrochemical aptamer sensor was proposed for the highly sensitive detection of mercury ion (Hg 2+ ). Carbon nanofiber (CNF) was prepared by electrospinning and high-temperature carbonization, which was used for the loading of platinum nanoparticles (PtNPs) by the hydrothermal method. The Pt@CNF nanocomposite was modified on the surface of carbon ionic liquid electrode (CILE) to obtain Pt@CNF/CILE, which was further decorated by gold nanoparticles (AuNPs) through electrodeposition to get Au/Pt@CNF/CILE. Self-assembling of the thiol-based aptamer was further realized by the formation of Au-S bond to get an electrochemical aptamer sensor (Aptamer/Au/Pt@CNF/CILE). Due to the specific binding of aptamer probe to Hg 2+ with the formation of T-Hg 2+ -T structure, a highly sensitive quantitative detection of Hg 2+ could be achieved by recording the changes of current signal after reacting with Hg 2+ within the concentration range from 1.0 × 10 −15 mol/L to 1.0 × 10 −6 mol/L and the detection limit of 3.33 × 10 −16 mol/L (3σ). Real water samples were successfully analyzed by this method.

Ultrasensitive electrochemical sensor for Hg2+ by using hybridization chain reaction coupled with Ag@Au core–shell nanoparticles

Zongbing Li,Xiangmin Miao,Ke Xing,Xue Peng,Aihua Zhu,Liansheng Ling

A novel electrochemical biosensor for Hg 2+ detection was reported by using DNA-based hybridization chain reaction (HCR) coupled with positively charged [email protected] core-shell nanoparticles ((+) [email protected] CSNPs) amplification. To construct the sensor, capture probe (CP ) was firstly immobilized onto the surface of glass carbon electrode (GCE). In the presence of Hg 2+ , the sandwiched complex can be formed between the immobilized CP on the electrode surface and the detection probe (DP) modified on the gold nanoparticles (AuNPs) based on T-Hg 2+ -T coordination chemistry. The carried DP then opened two ferrocene (Fc) modified hairpin DNA (H 1 and H 2 ) in sequence and propagated the happen of HCR to form a nicked double-helix. Numerous Fc molecules were formed on the neighboring probe and produced an obvious electrochemical signal. Moreover, (+) [email protected] CSNPs were assembly onto such dsDNA polymers as electrochemical signal enhancer. Under optimal conditions, such sensor presents good electrochemical responses for Hg 2+ detection with a detection limit of 3.6   pM. Importantly, the methodology has high selectivity for Hg 2+ detection.

Glypican-1-antibody-conjugated Gd–Au nanoclusters for FI/MRI dual-modal targeted detection of pancreatic cancer

Xin Huang,Chengqi Fan,Huanhuan Zhu,Wenjun Le,Shaobin Cui,Xin Chen,Wei Li,Fulei Zhang,Yong Huang,Donglu Sh,Zheng Cui,Chengwei Shao,Bingdi Chen

Electrochemical aptasensor based on PEI-Fe-MOF/Au@Ag NPs nanocomposites for streptomycin detection in dairy products

Haishuai Peng,Yuanyuan Hui,Meixue Pu,Ding Yang,Aiqing Zhao,Weizhe Wang,Shan Wu,Bini Wang

Streptomycin (STR) residues in dairy products could cause serious health risks for human or affect the quality of the dairy products fermented by lactic acid bacteria , thereby resulting in economic losses. Thus, STR detection methods need to be developed quickly, simply, and sensitively. In this study, polyethyleneimine (PEI)-functionalized NH 2 -MIL-101(Fe) (PEI-Fe-MOF) was characterized and found to exhibit an enhanced electrochemical characteristics, when compared to Fe-MOFs. [email protected] core-shell NPs could further amplify its electrochemical signal. Based on the PEI-Fe-MOF/ [email protected] NPs nanocomposites, we have developed a novel electrochemical aptasensor to detect STR rapidly. When detected under optimal conditions, a wide linear range between 0.1 and 200 nM was observed for the aptasensor with a detection limit of 0.033 nM. Furthermore, the developed aptasensor has been satisfactorily applied for the rapid STR detection in dairy products with recoveries ranging from 98.2% to 110.1%. Therefore, our method can be considered a new effective method for the rapid detection of STR in dairy products.

Plasmon-activated NO2 sensor based on Au@MoS2 core-shell nanoparticles with heightened sensitivity and full recoverability

Jinyong Hu,Xing Liu,Jiawei Zhang,Xin Gu,Yong Zhang

Developing high-performance gas-sensing devices based on transition metal dichalcogenides (TMDs) has sparked significant research interest in efficient detection of hazardous gases at room temperature . Considering that the gas-sensing performances of TMDs-based sensors can be effectively improved by the localized surface plasmon resonance (LSPR) effect of decorated noble-metal nanoparticles, herein, we explored the LSPR effect on gas-sensitive features via the design of a visible-light-assisted gas sensor using Au@MoS 2 core-shell heterostructures as sensitive materials. The internal connection between the optical absorption and the gas-sensing properties of Au@MoS 2 heterostructures was investigated. Intriguingly, under the activation of indoor white-light, the optimized Au@MoS 2 sensor displayed an enhanced response by more than 8 times and elevated recoverability from 60% to 98% almost without baseline shift as compared with the pure MoS 2 gas sensor for the detection of NO 2 (1 ppm). The combination of experimental and theoretical analysis indicates that the improved gas-sensing performances can be primarily attributed to the effective amplification of the light absorption efficiency of MoS 2 induced by the LSPR effect from the Au nanoparticle cores. These results imply a potential application in monitoring NO 2 gas at room temperature and open up an effective thoughtway for developing high-performance visible-light-modulated gas sensors.

Preparation of Ag Nanowire @ Au Nanoparticle Hybrid Nanowires and their Influence on the Fluorescence Properties of P3HT

Ming-Hai Zhang,Guo-Bin Yi,Xi-Hong Zu,Hai-Liang Huang,Yun-Jia Wang,Jian-Chao Wang,Ben-Bin Zhong,Hong-Sheng Luo

In this study, the galvanic displacement reaction between silver and AuCl 4 − was carried out to synthesize a series of silver nanowire (Ag NW) @ gold nanoparticle (Au NP) hybrid nanowires. The influence of Ag NW @ Au NP hybrid nanowires on the fluorescence properties of the poly (3-hexylthiophene) (P3HT) was investigated. The particle sizes of Au NPs on the hybrid nanowires could be adjusted by varying the reaction time and the concentration of the HAuCl 4 solution. Furthermore, steady-state fluorescence measurements showed that the fluorescence intensity of the P3HT films was higher on various Ag NW @ Au NP hybrid nanowires compared to that on a bare silicon substrate. This was due to the increase in the intensity of electromagnetic field by the localized surface plasmon resonances of Au NPs and surface plasmon polaritons of Ag NWs from the hybrid nanowires. The results were further confirmed by the Raman spectra of the P3HT films on different substrates.

Selective Mineralization and Recovery of Au(III) from Multi-Ionic Aqueous Systems by Bacillus licheniformis FZUL-63

Yangjian Cheng,Zhibin Ke,Xiaojing Bian,Jianhua Zhang,Zhen Huang,Yuancai Lv,Minghua Liu

The recovery of precious metals is a project with both economic and environmental significance. In this paper, how to use bacterial mineralization to selectively recover gold from multi-ionic aqueous systems is presented. TheBacillus licheniformisFZUL-63, isolated from a landscape lake in Fuzhou University, was shown to selectively mineralize and precipitate gold from coexisting ions in aqueous solution. The removal of Au(III) almost happened in the first hour. Scanning electron microscope with X-ray energy dispersive spectroscopy (SEM/EDS-mapping) results and fourier transform infrared spectroscopy (FTIR) data show that the amino, carboxyl, and phosphate groups on the surface of the bacteria are related to the adsorption of gold ions. X-ray photoelectron spectroscopy (XPS) results implied that Au(III) ions were reduced to those that were monovalent, and the Au(I) was then adsorbed on the bacterial surface at the beginning stage (in the first hour). X-ray diffraction (XRD) results showed that the gold biomineralization began about 10 h after the interaction between Au(III) ions and bacteria. Au(III) mineralization has rarely been influenced by other co-existing metal ions. Transmission electron microscope (TEM) analysis shows that the gold nanoparticles have a polyhedral structure with a particle size of ~20 nm. TheBacillus licheniformisFZUL-63 could selectively mineralize and recover 478 mg/g (dry biomass) gold from aqua regia-based metal wastewater through four cycles. This could be of great potential in practical applications.Keywords:selective biomineralization;recovery of Au(III);AuNP;Bacillus licheniformisFZUL-63;aqua regia-based metal wastewater

Plasmonic hot electron transfer in anisotropic Pt–Au nanodisks boosts electrochemical reactions in the visible-NIR region

Guanying Chen,Mingjuan Sun,Juan Li,Mingshan Zhu,Zaizhu Lou,Baojun Li

Anisotropic plasmonic metals have attracted significant attention in enhancing the catalytic performance of catalysts due to their broad light-harnessing capabilities and active hot electrons; however, limited investigations have been dedicated towards improving their electrochemical reaction performance in the visible and near infrared (NIR) regions. Herein, anisotropic Pt-edged Au nanodisks (NDs) were synthesized by controlling the preferential loading of Pt and used as catalysts for plasmon-enhanced electrochemical methanol oxidation reactions (MORs) under visible-NIR light irradiation by, and the light-enhanced electric current over the Pt-edged Au NDs was found to be 3-fold higher than that under dark conditions. Wavelength-dependent electric current over the Pt-edged Au NDs for the MOR in the visible-NIR light region demonstrates that the light-induced enhancement of the electric current is due to surface plasmon resonance (SPR) of the Au NDs. Furthermore, plasmonic hot electron transfer was studied by the single-particle photoluminescence images and spectra of Au NDs and Pt–Au NDs, and the dipole surface plasmon resonance (DSPR) mode was proved to be the main channel for hot electron transfer. During the electrochemical reaction under visible-NIR light irradiation, a plasmonic hot electron is transferred to the electrode, and a “hot hole” is left on the surface, boosting the MOR.

5-Hydroxymethylfurfural Hydrodeoxygenation Coupled with Water-Gas Shift Reaction for 2,5-Dimethylfuran Production over Au/ZrO2 Catalysts

Zhijian Li,Changhui Zhu,Haiyong Wang,Yuan Liang,Haosheng Xin,Song Li,Xiaohong Hu,Chenguang Wang,Qi Zhang,Qiying Liu,Longlong Ma

For the biomass catalytic valorization in the presence of a H2 atmosphere, large amounts of H2O and H2 are necessary to improve the processing efficiency, which resulted in the waste of such generous inputs. As a model reaction, the traditional hydrodeoxygenation of 5-hydroxymethylfurfural (5-HMF) selectively produces 2,5-dimethylfuran (2,5-DMF) under high pressure H2. Meanwhile, the water-gas shift reaction (WGSR) can counteract the harmful CO by simultaneously producing H2 from H2O. The hydrogenolysis of 5-HMF to 2,5-DMF produces H2O because of the hydroxyl group removal. Therefore, adding a trace amount of H2O to initiate 5-HMF hydrodeoxygenation coupled with WGSR to achieve H2O recycling in the reaction process is of great significance but extremely challenging. Herein, we reported a new process for the selective hydrodeoxygenation of 5-HMF to 2,5-DMF coupled with WGSR using a single catalyst, Au/ZrO2. A detailed study showed that the hydrogen species produced in situ by WGSR was used for 5-HMF hydrodeoxygenation to obtain 78.5% of 2,5-DMF yield. The H/H2O cycle in the coupling reactions exhibited a H2 utilization efficiency of 88.2%. Without using external H2, this work provided a new method for 5-HMF hydrodeoxygenation to 2,5-DMF triggered by WGSR and also showed the potential for application in H2O-saving conversion of cellulosic biomass with C–OH or C═O groups to value-added chemicals and fuels.