43 results on '"Yong Wang"'
Search Results
2. Robust radiosensitization of hemoglobin-curcumin nanoparticles suppresses hypoxic hepatocellular carcinoma
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Ruoling Gao, Yuan Gu, Ying Yang, Yuping He, Wenpeng Huang, Ting Sun, Zaixiang Tang, Yong Wang, and Wei Yang
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Hemoglobin ,Curcumin ,Nanoparticles ,Radiotherapy ,Hypoxia ,Hepatoma ,Biotechnology ,TP248.13-248.65 ,Medical technology ,R855-855.5 - Abstract
Abstract Background Radioresistance inducing by hypoxic microenvironment of hepatocellular carcinoma is a major obstacle to clinical radiotherapy. Advanced nanomedicine provides an alternative to alleviate the hypoxia extent of solid tumor, even to achieve effective synergistic treatment when combined with chemotherapy or radiotherapy. Results Herein, we developed a self-assembled nanoparticle based on hemoglobin and curcumin for photoacoustic imaging and radiotherapy of hypoxic hepatocellular carcinoma. The fabricated nanoparticles inhibited hepatoma migration and vascular mimics, and enhanced the radiosensitivity of hypoxic hepatoma cells in vitro via repressing cell proliferation and DNA damage repair, as well as inducing apoptosis. Benefit from oxygen-carrying hemoglobin combined with polyphenolic curcumin, the nanoparticles also effectively enhanced the photoacoustic contrast and the efficacy of radiotherapy for hepatocellular carcinoma in vivo. Conclusions Together, the current study offered a radiosensitization platform for optimizing the efficacy of nanomedicines on hypoxic radioresistant tumor. Graphical Abstract
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- 2022
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3. Detection Methods of Nanoparticles Synthesized by Gas-Phase Method: A Review
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Xiushuo Zhang, Xiaolong Zhao, Hongsheng Li, Xiaorui Hao, Jing Xu, Jingjing Tian, and Yong Wang
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gas-phase method ,nanoparticles ,detection methods ,review ,expectation ,Chemistry ,QD1-999 - Abstract
The detection of nanoparticles is the basis of the study of synthesis mechanism, active regulation of the synthesis process, and the study of nanoparticle properties after synthesis. It is significantly meaningful to the academia and engineering industry. Although there are many relevant detection methods at present, each method has its own advantages and disadvantages, and their measurement quantity and application conditions are also different. There is a lack of unified sorting and generalization. In this paper, the significance of detection of nanoparticles synthesized by a gas-phase method is introduced, the development of detection technology is reviewed, and the future is prospected. It is hoped that this paper will provide a reference for the detection of nanoparticles under various conditions and for the development of new detection methods.
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- 2022
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4. Bottom-Up Self-Assembly Based on DNA Nanotechnology
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Xuehui Yan, Shujing Huang, Yong Wang, Yuanyuan Tang, and Ye Tian
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self-assembly ,bottom-up ,DNA tile ,DNA brick ,DNA origami ,nanoparticles ,Chemistry ,QD1-999 - Abstract
Manipulating materials at the atomic scale is one of the goals of the development of chemistry and materials science, as it provides the possibility to customize material properties; however, it still remains a huge challenge. Using DNA self-assembly, materials can be controlled at the nano scale to achieve atomic- or nano-scaled fabrication. The programmability and addressability of DNA molecules can be applied to realize the self-assembly of materials from the bottom-up, which is called DNA nanotechnology. DNA nanotechnology does not focus on the biological functions of DNA molecules, but combines them into motifs, and then assembles these motifs to form ordered two-dimensional (2D) or three-dimensional (3D) lattices. These lattices can serve as general templates to regulate the assembly of guest materials. In this review, we introduce three typical DNA self-assembly strategies in this field and highlight the significant progress of each. We also review the application of DNA self-assembly and propose perspectives in this field.
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- 2020
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5. An Enhanced Performance of Glucose Biosensor Based on TiO2 Nanorod Arrays Decorated with Ag Nanoparticles.
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Minghui Chen, Jin Liu, Pengzhao Chang, Shaohui Zheng, and Yong Wang
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NANORODS ,GLUCOSE ,BIOSENSORS ,NANOPARTICLES ,CARBON paper ,GLUCOSE analysis ,HYDROTHERMAL synthesis ,GLUCOSE oxidase - Abstract
In this study, TiO
2 nanorod arrays (NAs) on carbon paper (CP) substrates were prepared via hydrothermal synthesis. Then, Ag nanoparticles (NPs) were deposited on the surface of the TiO2 NAs to enhance the electrocatalytic activity and analysis ability of the electrode for H2 O2 . Thereafter, GOx was modified on the surface of the Ag NPs-TiO2 NAs/CP via the cross-linking method for the detection of glucose. The GOx/Ag NPs-TiO2 NAs/CP integrates the functions of the specific recognition of glucose, signal transduction, and signal amplification. In an in vitro test, this GOx/Ag NPs-TiO2 NAs/CP biosensor shows a sensitivity of 0.182 mA mM-1 cm-2 , which is 6.6-fold that for the GOx/CP sensor (0.0276 mA mM-1 cm-2 ). The sensor can transduce the GOx-catalyzed reaction into significant current signals within 5 s. The relationship between the glucose concentration and the sensitivity to glucose is linear with the correlation coefficient R² of 0.9996 in the range of 0-0.9 mM, and the detection limit was estimated to be 1.6 µM. [ABSTRACT FROM AUTHOR]- Published
- 2023
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6. Two-stage assembly of nanoparticle superlattices with multiscale organization
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Yuxiang Dong, Jiliang Liu, Xuanzhao Lu, Jialin Duan, Liqi Zhou, Lizhi Dai, Min Ji, Ningning Ma, Yong Wang, Peng Wang, Jun-Jie Zhu, Qianhao Min, Oleg Gang, and Ye Tian
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Mechanical Engineering ,Nanoparticles ,Nanotechnology ,General Materials Science ,Bioengineering ,QD ,General Chemistry ,DNA ,Condensed Matter Physics ,QH426 ,QC ,Nanostructures - Abstract
Self-assembly processes, while promising for enabling the fabrication of complexly organized nanomaterials from nanoparticles, are often limited in creating structures with multiscale order. These limitations are due to difficulties in practically realizing the assembly processes required to achieve such complex organizations. For a long time, a hierarchical assembly attracted interest as a potentially powerful approach. However, due to the experimental limitations, intermediate-level structures are often heterogeneous in composition and structure, which significantly impacts the formation of large-scale organizations. Here, we introduce a two-stage assembly strategy: DNA origami frames scaffold a coordination of nanoparticles into designed 3D nanoclusters, and then these clusters are assembled into ordered lattices whose types are determined by the clusters' valence. Through modulating the nanocluster architectures and intercluster bindings, we demonstrate the successful formation of complexly organized nanoparticle crystals. The presented two-stage assembly method provides a powerful fabrication strategy for creating nanoparticle superlattices with prescribed unit cells.
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- 2022
7. Electron penetration triggering interface activity of Pt-graphene for CO oxidation at room temperature
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Xinhe Bao, Yanping Zheng, Ye Wang, Yunchuan Tu, Liang Yu, Chao Ma, Dehui Deng, Jingting Hu, Zhongmiao Gong, Wujun Zhang, Yong Wang, Fan Yang, Mingshu Chen, Pengju Ren, and Yi Cui
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inorganic chemicals ,Materials science ,Science ,Alloy ,Oxide ,General Physics and Astronomy ,Nanoparticle ,engineering.material ,Heterogeneous catalysis ,General Biochemistry, Genetics and Molecular Biology ,Article ,law.invention ,Catalysis ,chemistry.chemical_compound ,Adsorption ,Transition metal ,law ,Multidisciplinary ,Graphene ,General Chemistry ,Chemical engineering ,chemistry ,engineering ,Nanoparticles - Abstract
Achieving CO oxidation at room temperature is significant for gas purification but still challenging nowadays. Pt promoted by 3d transition metals (TMs) is a promising candidate for this reaction, but TMs are prone to be deeply oxidized in an oxygen-rich atmosphere, leading to low activity. Herein we report a unique structure design of graphene-isolated Pt from CoNi nanoparticles (PtǀCoNi) for efficiently catalytic CO oxidation in an oxygen-rich atmosphere. CoNi alloy is protected by ultrathin graphene shell from oxidation and therefore modulates the electronic property of Pt-graphene interface via electron penetration effect. This catalyst can achieve near 100% CO conversion at room temperature, while there are limited conversions over Pt/C and Pt/CoNiOx catalysts. Experiments and theoretical calculations indicate that CO will saturate Pt sites, but O2 can adsorb at the Pt-graphene interface without competing with CO, which facilitate the O2 activation and the subsequent surface reaction. This graphene-isolated system is distinct from the classical metal-metal oxide interface for catalysis, and it provides a new thought for the design of heterogeneous catalysts., Achieving CO oxidation at room temperature is significant for gas purification but remains challenging to perform. Here, the authors report design of graphene-isolated Pt from cobalt-nickel nanoparticles for efficiently catalytic CO oxidation in an oxygen-rich atmosphere.
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- 2021
8. Multispectral optoacoustic imaging of dynamic redox correlation and pathophysiological progression utilizing upconversion nanoprobes
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Ruochong Zhang, Zhimin Wang, Yuanjin Zheng, Yong Wang, Haolun Cheong, Mingyuan Gao, Bengang Xing, Xiangzhao Ai, and Jun Lin
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0301 basic medicine ,Science ,Multispectral image ,Wavelength channels ,Deep penetration ,Mice, Nude ,General Physics and Astronomy ,Nanoprobe ,02 engineering and technology ,Kidney ,Redox ,Theranostic Nanomedicine ,Article ,General Biochemistry, Genetics and Molecular Biology ,Photoacoustic Techniques ,Mice ,03 medical and health sciences ,Animals ,Humans ,lcsh:Science ,Lung ,Fluorescent Dyes ,Inflammation ,Mice, Inbred BALB C ,Photons ,Spectroscopy, Near-Infrared ,Multidisciplinary ,Chemistry ,Heart ,General Chemistry ,021001 nanoscience & nanotechnology ,Photon upconversion ,Disease Models, Animal ,RAW 264.7 Cells ,030104 developmental biology ,Liver ,Molecular Probes ,Biophysics ,Nanoparticles ,Female ,lcsh:Q ,Spatiotemporal resolution ,Tomography, X-Ray Computed ,0210 nano-technology ,Oxidation-Reduction ,Biomarkers ,Spleen ,Optoacoustic imaging - Abstract
Precise and differential profiling of the dynamic correlations and pathophysiological implications of multiplex biological mediators with deep penetration and highly programmed precision remain critical challenges in clinics. Here we present an innovative strategy by tailoring a powerful multispectral optoacoustic tomography (MSOT) technique with a photon-upconverting nanoprobe (UCN) for simultaneous visualization of diversely endogenous redox biomarkers with excellent spatiotemporal resolution in living conditions. Upon incorporating two specific radicals-sensitive NIR cyanine fluorophores onto UCNs surface, such nanoprobes can orthogonally respond to disparate oxidative and nitrosative stimulation, and generate spectrally opposite optoacoustic signal variations, which thus achieves compelling superiorities for reversed ratiometric tracking of multiple radicals under dual independent wavelength channels, and significantly, for precise validating of their complex dynamics and correlations with redox-mediated pathophysiological procession in vivo., Reactive oxygen (ROS) and nitrogen (RNS) species are involved in key physiological processes and their balance is altered in various human diseases. Here the authors develop near-infrared upconversion nanoprobes to screen ROS/RNS dynamics simultaneously by multispectral optoacoustic imaging in vivo.
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- 2019
9. A new analysis method for evaluating bacterial growth with microplate readers
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Venkata Rao Krishnamurthi, Jingyi Chen, Yong Wang, and Isabelle I. Niyonshuti
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Protein Expression ,Metal Nanoparticles ,Bacterial growth ,Biochemistry ,Silver nanoparticle ,Mathematical and Statistical Techniques ,Microbial Physiology ,Nanotechnology ,Analysis method ,0303 health sciences ,Multidisciplinary ,Chemistry ,Microbial Growth and Development ,Growth curve (biology) ,Microbial Cultures ,Fluorescence ,Curve Fitting ,Physical Sciences ,Curve fitting ,Medicine ,Engineering and Technology ,Biological Cultures ,Biological system ,Research Article ,Chemical Elements ,Silver ,Science ,Gompertz function ,Bacterial Cultures ,Research and Analysis Methods ,Microbiology ,Green Fluorescent Protein ,03 medical and health sciences ,Gene Expression and Vector Techniques ,Molecular Biology Techniques ,Molecular Biology ,030304 developmental biology ,Molecular Biology Assays and Analysis Techniques ,Bacteria ,Escherichia coli K12 ,030306 microbiology ,Bacterial Growth ,Organisms ,Biology and Life Sciences ,Proteins ,Luminescent Proteins ,Temporal resolution ,Nanoparticles ,Mathematical Functions ,Developmental Biology ,Densitometry - Abstract
Growth curve measurements are commonly used in microbiology, while the use of microplate readers for such measurements provides better temporal resolution and higher throughput. However, evaluating bacterial growth with microplate readers has been hurdled by barriers such as multiple scattering. Here, we report our development of a method based on the time derivatives of the optical density (OD) and/or fluorescence (FL) of bacterial cultures to overcome these barriers. First, we illustrated our method using quantitative models and numerical simulations, which predicted the number of bacteria and the number of fluorescent proteins in time as well as their time derivatives. Then, we systematically investigated how the time derivatives depend on the parameters in the models/simulations, providing a framework for understanding the FL growth curves. In addition, as a demonstration, we applied our method to study the lag time elongation of bacteria subjected to treatment with silver (Ag+) ions and found that the results from our method corroborated well with that from growth curve fitting by the Gompertz model that has been commonly used in the literature. Furthermore, this method was applied to the growth of bacteria in the presence of silver nanoparticles (AgNPs) at various concentrations, where the OD curve measurements failed. We showed that our method allowed us to successfully extract the growth behavior of the bacteria from the FL measurements and understand how the growth was affected by the AgNPs.
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- 2021
10. Tumor-targeted Gd-doped mesoporous Fe3O4 nanoparticles for T1/T2 MR imaging guided synergistic cancer therapy.
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Shaohui Zheng, Shang Jin, Min Jiao, Wenjun Wang, Xiaoyu Zhou, Jie Xu, Yong Wang, Peipei Dou, Zhen Jin, Changyu Wu, Jingjing Li, Xinting Ge, and Kai Xu
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MAGNETIC resonance imaging ,CANCER treatment ,PHOTOTHERMAL conversion ,CONTRAST effect ,IRON oxide nanoparticles ,NANOPARTICLES - Abstract
In this study, a novel intelligent nanoplatform to integrate multiple imaging and therapeutic functions for targeted cancer theranostics. The nanoplatform, DOX@Gd-MFe
3 O4 NPs, was constructed Gd-doped mesoporous Fe3 O4 nanoparticles following with the doxorubicin (DOX) loading in the mesopores of the NPs. The DOX@Gd-MFe3 O4 NPs exhibited good properties in colloidal dispersity, photothermal conversion, NIR triggered drug release, and high T1 /T2 relaxicity rate (r1 =9.64mM-1 s-1 , r2 = 177.71mM-1 s-1 ). Benefiting from the high MR contrast, DOX@Gd-MFe3O4 NPs enabled simultaneous T1 /T2 dual-modal MR imagining on 4T1 bearing mice in vivo and the MR contrast effect was further strengthened by external magnetic field. In addition, the DOX@Gd-MFe3 O4 NPs revealed the strongest inhibition to the growth of 4T1 in vitro and in vivo under NIR irradiation and guidance of external magnetic field. Moreover, biosafety was also validated by in vitro and in vivo tests. Thus, the prepared DOX@Gd-MFe3 O4 NPs would provide a promising intelligent nanoplatform for dual-modal MR imagining guided synergistic therapy in cancer theranostics. [ABSTRACT FROM AUTHOR]- Published
- 2021
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11. Glycyrrhetinic acid-modified chitosan nanoparticles enhanced the effect of 5-fluorouracil in murine liver cancer model via regulatory T-cells
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Xiaoyan Gao, Hongzhi Xu, Houxiang Chen, Bing He, Yingchun Li, Mingrong Cheng, Jiang Han, Zhiping Zhang, and Yong Wang
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Interleukin 2 ,Antimetabolites, Antineoplastic ,Time Factors ,glycyrrhetinic acid ,Pharmaceutical Science ,Pharmacology ,T-Lymphocytes, Regulatory ,regulatory T cells ,Chitosan ,Interferon-gamma ,Mice ,chemistry.chemical_compound ,Liver Neoplasms, Experimental ,In vivo ,Drug Discovery ,medicine ,Animals ,Cytotoxic T cell ,Interferon gamma ,5-fluorouracil ,Particle Size ,Cell Proliferation ,Original Research ,Drug Carriers ,Mice, Inbred BALB C ,Drug Design, Development and Therapy ,Dose-Response Relationship, Drug ,targeted therapy ,In vitro ,Retraction ,nervous system diseases ,Killer Cells, Natural ,Survival Rate ,chemistry ,Delayed-Action Preparations ,Cancer cell ,Biophysics ,Interleukin-2 ,Nanoparticles ,Female ,Fluorouracil ,Drug carrier ,hepatic carcinoma ,T-Lymphocytes, Cytotoxic ,medicine.drug - Abstract
This paper has beenretracted.Mingrong Cheng,1,2,* Hongzhi Xu,3,* Yong Wang,4,* Houxiang Chen,5 Bing He,3 Xiaoyan Gao,6 Yingchun Li,2 Jiang Han,1 Zhiping Zhang1 1Department of General Surgery, 2Department of Endoscopy, Pudong New Area District Zhoupu Hospital, Shanghai, People’s Republic of China; 3Department of General Surgery, Shanghai Fifth People’s Hospital, Fudan University, Shanghai, People’s Republic of China; 4School of Materials Science and Engineering, Wuhan University of Technology, Wuhan, People’s Republic of China; 5Zhejiang Huafon Fiber Research Institute, Zhejiang Huafon Spandex Co, Ltd, Wenzhou, People’s Republic of China; 6Department of Plastic Surgery, Pudong New Area District Zhoupu Hospital, Shanghai, People’s Republic of China *These authors contributed equally to this work Abstract: Modified chitosan nanoparticles are a promising platform for drug, such as 5-fluorouracil (5-FU), gene, and vaccine delivery. Here, we used chitosan and hepatoma cell-specific binding molecule glycyrrhetinic acid (GA) to synthesize glycyrrhetinic acid-modified chitosan (GA-CTS). The synthetic product was confirmed by infrared spectroscopy and hydrogen nuclear magnetic resonance. By combining GA-CTS and 5-FU, we obtained a GA-CTS/5-FU nanoparticle, with a particle size of 193.7 nm, drug loading of 1.56%, and a polydispersity index of 0.003. The GA-CTS/5-FU nanoparticle provided a sustained-release system comprising three distinct phases of quick, steady, and slow release. In vitro data indicated that it had a dose- and time-dependent anticancer effect. The effective drug exposure time against hepatic cancer cells was increased in comparison with that observed with 5-FU. In vivo studies on an orthotropic liver cancer mouse model demonstrated that GA-CTS/5-FU significantly inhibited cancer cell proliferation, resulting in increased survival time. The antitumor mechanisms for GA-CTS/5-FU nanoparticle were possibly associated with an increased expression of regulatory T-cells, decreased expression of cytotoxic T-cell and natural killer cells, and reduced levels of interleukin-2 and interferon gamma. Keywords: hepatic carcinoma, regulatory T cells, glycyrrhetinic acid, targeted therapy, 5-fluorouracil
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- 2013
12. Synthesis of Glycyrrhetinic Acid-Modified Chitosan 5-Fluorouracil Nanoparticles and Its Inhibition of Liver Cancer Characteristics in Vitro and in Vivo
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Houxiang Chen, Xiaoyan Gao, Bing He, Yingchun Li, Mingrong Cheng, Jiang Han, Yong Wang, Hongzhi Xu, and Zhiping Zhang
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Carcinoma, Hepatocellular ,glycyrrhetinic acid ,Pharmaceutical Science ,Nanoparticle ,hepatic carcinoma ,regulatory T-cells ,targeted therapy ,5-fluorouracil ,Pharmacology ,Article ,Cell Line ,Chitosan ,chemistry.chemical_compound ,Mice ,Drug Delivery Systems ,In vivo ,Cell Line, Tumor ,Drug Discovery ,Animals ,Humans ,Particle Size ,Pharmacology, Toxicology and Pharmaceutics (miscellaneous) ,lcsh:QH301-705.5 ,Drug Carriers ,Mice, Inbred BALB C ,Chemistry ,Liver Neoplasms ,In vitro ,Liver ,lcsh:Biology (General) ,Cell culture ,Drug delivery ,Cancer cell ,Biophysics ,Nanoparticles ,Female ,Fluorouracil ,Drug carrier - Abstract
Nanoparticle drug delivery (NDDS) is a novel system in which the drugs are delivered to the site of action by small particles in the nanometer range. Natural or synthetic polymers are used as vectors in NDDS, as they provide targeted, sustained release and biodegradability. Here, we used the chitosan and hepatoma cell-specific binding molecule, glycyrrhetinic acid (GA), to synthesize glycyrrhetinic acid-modified chitosan (GA-CTS). The synthetic product was confirmed by Fourier transformed infrared spectroscopy (FT-IR) and 1H-nuclear magnetic resonance (1H-NMR). By combining GA-CTS and 5-FU (5-fluorouracil), we obtained a GA-CTS/5-FU nanoparticle, with a particle size of 217.2 nm, a drug loading of 1.56% and a polydispersity index of 0.003. The GA-CTS/5-FU nanoparticle provided a sustained release system comprising three distinct phases of quick, steady and slow release. We demonstrated that the nanoparticle accumulated in the liver. In vitro data indicated that it had a dose- and time-dependent anti-cancer effect. The effective drug exposure time against hepatic cancer cells was increased in comparison with that observed with 5-FU. Additionally, GA-CTS/5-FU significantly inhibited the growth of drug-resistant hepatoma, which may compensate for the drug-resistance of 5-FU. In vivo studies on an orthotropic liver cancer mouse model demonstrated that GA-CTS/5-FU significantly inhibited tumor growth, resulting in increased survival time.
- Published
- 2013
13. SnO2@MoO2/Carbon Ternary Hollow Nanocomposites with Robust Shell as High-Performance Lithium-Ion-Battery Anodes.
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Yong Wang, Peiyuan Mao, Shun Rao, Wenbin Guo, Fanchao Zhang, Pandeng Xiao, and Wen Zhang
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METALLIC oxides ,STRUCTURAL design ,NANOSTRUCTURED materials ,ENERGY conversion ,NANOPARTICLES ,ANNEALING of metals - Abstract
SnO
2 @MoO2 /carbon hollow nanospheres are successfully fabricated by coating a Mo-polydopamine chelate precursor on SiO2@SnO2 nanospheres, with subsequent annealing and HF corrosion. In the unique nanocomposites, the external carbon layer with MoO2 nanoparticles and a SnO2 hollow inner layer as the skeleton can not only enhance electronic conductivity, but also reinforce the shell of the hollow nanocomposites while preventing the aggregation of SnO2 and MoO2 nanoparticles during intensive cycles, thus enhancing the structural integrity, rate capability and cyclic stability. In virtue of the respective roles and synergistic effects of the three nanocomponents, the unique ternary nanocomposites possess an initial discharge capacity of 1097 mAhg-1 , high initial coulombic efficiency of 85%, and good cyclic performance (725 mAhg-1 after 300 cycles) as anode nanomaterials. The structural design of the MoO2 /C layer coating metal-oxide hollow nanospheres can provide a novel synthetic approach for other hybrid energy nanomaterials with excellent properties. [ABSTRACT FROM AUTHOR]- Published
- 2020
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14. Process optimization and evaluation of novel baicalin solid nanocrystals
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Pengfei Yue, Yong Wang, Jing Wan, Changhong Wang, Ming Yang, Hai-Long Yuan, Wei-Feng Zhu, and Yu Li
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Materials science ,animal structures ,solid nanocrystals ,Scanning electron microscope ,Biophysics ,Analytical chemistry ,Pharmaceutical Science ,Biological Availability ,Bioengineering ,Biomaterials ,chemistry.chemical_compound ,Differential scanning calorimetry ,International Journal of Nanomedicine ,Drug Discovery ,Animals ,Solubility ,Particle Size ,Rats, Wistar ,baicalin ,Dissolution ,Original Research ,Flavonoids ,Analysis of Variance ,Organic Chemistry ,in vivo/vitro evaluation ,General Medicine ,Bioavailability ,Rats ,chemistry ,Transmission electron microscopy ,Microscopy, Electron, Scanning ,Nanoparticles ,Particle size ,Baicalin ,optimization ,Nuclear chemistry - Abstract
Peng-Fei Yue,1,2 Yu Li,1 Jing Wan,1 Yong Wang,1 Ming Yang,1 Wei-Feng Zhu,1 Chang-Hong Wang,2 Hai-Long Yuan31Key Lab of Modern Preparation of TCM, Jiangxi University of Traditional Chinese Medicine, Nanchang, 2Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai, 3302 Hospital of PLA Institute of Chinese Materia Medica, Beijing, People's Republic of ChinaAbstract: The objective of this study was to prepare baicalin solid nanocrystals (BCN-SNS) to enhance oral bioavailability of baicalin. A Box–Behnken design approach was used for process optimization. The physicochemical properties and pharmacokinetics of the optimal BCN-SNS were investigated. Multiple linear regression analysis for process optimization revealed that the fine BCN-SNS was obtained wherein the optimal values of homogenization pressure (bar), homogenization cycles (cycles), amount of TPGS to drug (w/w), and amount of MCCS to drug (w/w) were 850 bar, 25 cycles, 10%, and 10%, respectively. Transmission electron microscopy and scanning electron microscopy results indicated that no significant aggregation or crystal growth could be observed in the redispersed freeze-dried BCN-SNS. Differential scanning calorimetry and X-ray diffraction results showed that BCN remained in a crystalline state. Dissolution velocity of the freeze-dried BCN-SNS powder was distinctly superior compared to those of the crude powder and physical mixture. The bioavailability of BCN in rats was increased remarkably after oral administration of BCN-SNS (P < 0.05), compared with those of BCN or the physical mixture. The SNS might be a good choice for oral administration of poorly soluble BCN, due to an improvement of the bioavailability and dissolution velocity of BCN-SNS.Keywords: baicalin, solid nanocrystals, optimization, in vivo/vitro evaluation
- Published
- 2013
15. Preparation and Characterization of Novel Perfluorooctyl Bromide Nanoparticle as Ultrasound Contrast Agent via Layer-by-Layer Self-Assembly for Folate-Receptor-Mediated Tumor Imaging
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Shengmin Zhang, Keshi Li, Yong Wang, Baosan Han, Yahui Liu, Yue Hu, Jianshuai Jiang, and ShuXiong Ge
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Diagnostic Imaging ,Materials science ,Carcinoma, Hepatocellular ,Biocompatibility ,Article Subject ,Cell Survival ,Nanoparticle ,lcsh:Medicine ,Contrast Media ,Receptors, Cell Surface ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Hemolysis ,General Biochemistry, Genetics and Molecular Biology ,chemistry.chemical_compound ,Folic Acid ,Dynamic light scattering ,Drug Stability ,Bromide ,Cell Line, Tumor ,Materials Testing ,Zeta potential ,Humans ,Particle Size ,Ultrasonography ,Fluorocarbons ,General Immunology and Microbiology ,business.industry ,Ultrasound ,lcsh:R ,Liver Neoplasms ,Temperature ,General Medicine ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Hydrocarbons, Brominated ,chemistry ,Folate receptor ,Biophysics ,Nanoparticles ,Molecular imaging ,0210 nano-technology ,business ,Research Article - Abstract
A folate-polyethylene glycol-chitosan derivative was synthesized and its structure was characterized. An optimal perfluorooctyl bromide nanocore template was obtained via utilizing the ultrasonic emulsification method combining with orthogonal design. The targeted nanoparticles containing targeted shell of folate-polyethylene glycol-chitosan derivative and perfluorooctyl bromide nanocore template of ultrasound imaging were prepared successfully by exploiting layer-by-layer self-assembly as contrast agent for ultrasound. Properties of the novel perfluorooctyl bromide nanoparticle were extensively studied by Dynamic Light Scattering and Transmission Electron Microscopy. The targeted nanoparticle diameter, polydispersity, and zeta potential are around 229.5 nm, 0.205, and44.7±0.6 mV, respectively. The study revealed that spherical core-shell morphology was preserved. Excellent stability of targeted nanoparticle is evidenced by two weeks of room temperature stability tests. The results of the cell viability assay and the hemolysis test confirmed that the targeted nanoparticle has an excellent biocompatibility for using in cell studies and ultrasound imaging in vivo. Most importantly, in vitro cell experiments demonstrated that an increased amount of targeted nanoparticles was accumulated in hepatocellular carcinoma cell line Bel7402 relative to hepatoma cell line L02. And targeted nanoparticles had also shown better ultrasound imaging abilities in vitro. The data suggest that the novel targeted nanoparticle may be applicable to ultrasonic molecular imaging of folate-receptor overexpressed tumor.
- Published
- 2016
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16. Unique size-dependent nanocatalysis revealed at the single atomically precise gold cluster level.
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Yuwei Zhang, Ping Song, Tiankai Chen, Xiaodong Liu, Tao Chen, Zhemin Wu, Yong Wang, Jianping Xie, and Weilin Xu
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CATALYSIS ,GOLD clusters ,NANOPARTICLES ,DISSOCIATION (Chemistry) ,QUANTUM chemistry ,ELECTRONIC structure ,FLUORESCENCE microscopy - Abstract
Atomically precise metal clusters have attracted increasing interest owing to their unique size-dependent properties; however, little has been known about the effect of size on the catalytic properties of metal clusters at the single-cluster level. Here, by real-time monitoring with single-molecule fluorescence microscopy the size-dependent catalytic process of individual Au clusters at single-turnover resolution, we study the size-dependent catalytic behaviors of gold (Au) clusters at the single-cluster level, and then observe the strong size effect on the catalytic properties of individual Au clusters, in both catalytic product formation and dissociation processes. Surprisingly, indicated by both experiments and density functional theory (DFT) calculations, due to such a unique size effect, besides observing the different product dissociation behaviors on different-sized Au clusters, we also observe that small Au clusters [i.e., Au
15 (MPA)13 ; here, MPA denotes 3-mercaptopropionic acid] catalyze the product formation through a competitive Langmuir-Hinshelwood mechanism, while those relatively larger Au clusters [e.g., Au18 (MPA)14 and Au25 (MPA)18 ] or nanoparticles catalyze the same process through a noncompetitive Langmuir-Hinshelwood mechanism. Such a size effect on the nanocatalysis could be attributed intrinsically to the size-dependent electronic structure of Au clusters. Further analysis of dynamic activity fluctuation of Au clusters reveals more different catalytic properties between Au clusters and traditional Au nanoparticles due to their different size-dependent structures. [ABSTRACT FROM AUTHOR]- Published
- 2018
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17. Fabrication and photocatalytic properties of CuO/SiO2 heterogeneous hollow cubes.
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Yong Wang, Chao Wang, Ming-Gui Zou, Dong-Xia Wang, Qing-Yuan Li, and Wen-Bin Guo
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COPPER oxide , *PHOTOCATALYSIS , *NANOPARTICLES , *NANOSTRUCTURES , *SCANNING electron microscopy - Abstract
CuO/SiO2 heterogeneous hollow cubes have been successfully fabricated under hydrothermal conditions. XRD, SEM and EDX under TEM studies confirm that CuO nanoparticles deposit on the surface of SiO2 hollow cubic templates. In virtue of their heterogeneous and hollow structures as well as higher specific surface area, CuO/SiO2 heterogeneous hollow cubes exhibit enhanced photocatalytic properties compared to P25 TiO2, SiO2 hollow cubes and CuO hierarchical microflowers. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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18. Remote multi-color excitation using femtosecond propagating surface plasmon polaritons in gold films
- Author
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Yong Wang, Eric O. Potma, Xuejun Liu, Wendong Xing, and Desire Whitmore
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Materials science ,Light ,interference ,Color ,Physics::Optics ,silver electrode ,law.invention ,Optics ,enhanced raman-spectroscopy ,law ,generation ,Quantum Dots ,Physical Sciences and Mathematics ,Scattering, Radiation ,Sum-frequency generation ,business.industry ,Surface plasmon ,scattering ,Life Sciences ,Membranes, Artificial ,Surface Plasmon Resonance ,Laser ,Surface plasmon polariton ,Atomic and Molecular Physics, and Optics ,nanowires ,Quantum dot ,Femtosecond ,Optoelectronics ,nanoparticles ,Gold ,wave-guides ,business ,nanorods ,light ,Excitation ,Localized surface plasmon - Abstract
We demonstrate dual-color nonlinear excitation of quantum dots positioned onto a gold film at distances up to 40 mu m away from a micrometer sized focused laser spot. We attribute the observed remote nonlinear signal to the excitation of two independent surface plasmon polariton (SPP) modes excited at the laser spot in the gold film, which subsequently propagate in a collinear fashion to a distant site and provide the surface field required for nonlinear excitation of the target. This scheme decouples the illuminating photon flux from surface plasmon mediated nonlinear excitation of the target, which provides more control of unwanted heating effects at the target site and represents an attractive approach for surface-mediated femtosecond nonlinear examinations of molecules. (C) 2011 Optical Society of America
- Published
- 2011
19. Determination of hydrogen peroxide using a biosensor based on Fe3O4 magnetic nanoparticles and horseradish peroxidase with graphene-chitosan composite.
- Author
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Jianying Qu, Ying Dong, Yong Wang, Tongfang Lou, and Xueping Du
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HYDROGEN peroxide ,BIOSENSORS ,GRAPHENE ,NANOPARTICLES ,SURFACE active agents ,TRANSMISSION electron microscopy - Abstract
A novel hydrogen peroxide (H
2 O2 ) biosensor was constructed based on Fe3 O4 magnetic nanoparticles (MNPs) and horseradish peroxidase with graphene-chitosan composite material as a matrix. Fe3 O4 MNPs were synthesised by chemical co-precipitation with sodium citrate as surfactant. Fourier transform infrared spectroscopy and transmission electron microscopy were applied for the characterisation of the obtained Fe3 O4 MNPs. The conductivity of different composite films was researched by electrochemical impedance spectroscopy and the electrocatalytic properties of the H2 O2 biosensor were studied by cyclic voltammetry. Under optimal conditions, experimental results indicated that the biosensor could electrocatalyse the reduction of H2 O2 ; the reduction peak current had a good linear relationship with the concentration of H2 O2 from 2.49 × 10-5 to 1.67 × 10-3 mol/l (R = 0.9990). The detection limit was 3.05 × 10-6 mol/l (S/N = 3). This novel biosensor showed good sensitivity, stability and repeatability for H2 O2 detection. [ABSTRACT FROM AUTHOR]- Published
- 2014
- Full Text
- View/download PDF
20. Water Uptake of a Sandwich-Structured Composite Film Coated on a Mg-Gd-Y Alloy: Experiments and Model Validation.
- Author
-
Xinghua Guo, Keqin Du, Quanzhong Guo, Hao Ge, Yong Wang, Rong Wang, and Fuhui Wang
- Subjects
COMPOSITE materials ,MAGNESIUM alloys ,DIFFUSION ,WATER ,NANOPARTICLES ,INTERFACES (Physical sciences) - Abstract
Water diffusion in a sandwich-structured composite film on a Mg-Gd-Y alloy was experimentally investigated using electrochemical impedance spectroscopy (EIS). The composite film contained an inner integration layer and an outer fluorocarbon (FC) layer. The integration layer was prepared by depositing an environment-friendly self-assembled nanoparticle film on the surface of a plasma electrolytic oxidation film. The resulting structure is therefore referred to as PSF. The measured value of the diffusion coefficient of the PSF film by the EIS method was compared to the value predicted using a mathematical model. The noncontinuity of the water concentration at the interface of the integration and FC layers resulted in a significant difference between the diffusion coefficients obtained by the experimental EIS method and mathematical model. A coefficient "k
e " was introduced to the Fick's first law of diffusion, and a PSF model validation was used to confirm the concentration jump on the FC-integration boundary of the PSF film. When ke ≪ 1, the calculated diffusion coefficient (DM err ) of the PSF film by the mathematical model was found similar to that obtained by the EIS experimental method. [ABSTRACT FROM AUTHOR]- Published
- 2014
- Full Text
- View/download PDF
21. Large and fast reversible Li-ion storages in Fe2O3-graphene sheet-on-sheet sandwich-like nanocomposites.
- Author
-
Jin Kan and Yong Wang
- Subjects
- *
NANOPARTICLES , *OPTICAL properties , *OPTICAL properties of graphene , *AGGLOMERATION (Materials) , *LITHIUM-ion batteries , *SURFACE area , *INDUSTRIAL concentration - Abstract
Fe2O3 nanosheets and nanoparticles are grown on graphene by simply varying reaction solvents in a facile solvothermal/hydrothermal preparation. Fe2O3 nanosheets are uniformly dispersed among graphene nanosheets, forming a unique sheet-on-sheet nanostructure. Due to the structure affinity between two types of two dimensional nanostructures, graphene nanosheets are separated better by Fe2O3 nanosheets compared to nanoparticles and their agglomeration is largely prevented. Alarge surface area of 173.9 m2 g-1 is observed for Fe2O3-graphene sheet-on-sheet composite, which is more than two times as large as that of Fe2O3-graphene particle-on-sheet composite (81.5 m2 g-1). The sheet-on-sheet composite is found to be better suitable as an anode for Li-ion battery. A high reversible capacity of 662.4 mAh g-1 can be observed after 100 cycles at 1000 mA g-1. The substantially improved cycling performance is ascribed to the unique structure affinity between Fe2O3 nanosheets and graphene nanosheets, thus offering complementary property improvement. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
22. Uniform and Conformal Carbon Nanofilms Produced Based on Molecular Layer Deposition.
- Author
-
Peng Yang, Guizhen Wang, Zhe Gao, He Chen, Yong Wang, and Yong Qin
- Subjects
LIGHT elements ,POLYMERS ,NANOPARTICLES ,ALUMINUM oxide ,CHEMICAL reactions - Abstract
Continuous and uniform carbon nanofilms (CNFs) are prepared by pyrolysis of polyimide films which are produced by molecular layer deposition (MLD). The film thickness can be easily controlled at nanometer scale by altering the cycle numbers. During the annealing process at 600 °C, the polyimide film is subject to shrinkage of 70% in thickness. The obtained CNFs do not exhibit a well-graphitized structure due to the low calcination temperature. No clear pore structures are observed in the produced films. CNFs grown on a glass substrate with a thickness of about 1.4 nm shows almost 98% optical transmittance in the visible spectrum range. Au nanoparticles coated with CNFs are produced by this method. Carbon nanotubes with uniform wall thickness are obtained using anodic aluminum oxide as a template by depositing polyimide films into its pores. Our results demonstrate that this method is very effective to coat conformal and uniform CNFs on various substrates, such as nanoparticles and porous templates, to produce functional composite nanomaterials. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
23. Mesoporous Block Copolymer Nanorods by Swelling-Induced Morphology Reconstruction.
- Author
-
Yong Wang, Martin Steinhart, and Ulrich Gösele
- Subjects
- *
BLOCK copolymers , *NANOPARTICLES , *MORPHOGENESIS , *TRANSITION (Rhetoric) - Abstract
Engineering the topography of thin block copolymer (BCP) films by surface reconstruction associated with selective swelling of one of the blocks has been investigated intensively. Here we show that swelling-induced structural transitions in nanorods consisting of amphiphilic BCPs involve pronounced reshaping of the nonswollen glassy domains in the course of the transition from the equilibrium morphology of the molten BCP in cylindrical confinement to that of the BCP dissolved in the swelling agent. The reconstruction process can be quenched to retain intermediate nonequilibrium morphologies. The collapse of the swollen chains upon drying yields polymeric nanorods exhibiting complex nanoscopic architectures characterized by a variety of mesopore structures and surface topographies, including channels along the nanorods, bunches of partially interconnected strands, and strings of spheres. The complex BCP nanorods thus obtained can be used as soft templates for the rational arrangement of metal nanoparticles. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
24. Synthesis of iron oxide nanoparticles using a freshly-made or recycled imidazolium-based ionic liquid.
- Author
-
Yong Wang, Sean Maksimuk, Rui Shen, and Hong Yang
- Subjects
- *
FERRIC oxide , *NANOPARTICLES , *ELECTRON microscopy , *METALLIC oxides - Abstract
This paper reports the synthesis of iron oxide nanoparticles using a freshly-made or recycled 1-butyl-3-methylimidazolium bis(triflylmethylsulfonyl)imide ([BMIM][Tf2N]) ionic liquid (IL). Iron pentacarbonyl (Fe(CO)5), which dissolves in [BMIM][Tf2N], thermally decomposed and subsequently oxidized to form iron oxide nanoparticles. These nanoparticles separated out automatically from the imidazolium-based ionic liquid mixtures. Multiple additional runs were tested in making iron oxide nanoparticles using recycled ionic liquid. The iron oxide nanoparticles made were characterized with transmission electron microscopy (TEM), high resolution TEM (HR-TEM) and powder X-ray diffraction (PXRD). The structure and thermal stability of the IL was examined using Fourier transform infrared (FT-IR) spectroscopy and thermal gravimetric analysis (TGA). We found that iron oxide nanoparticles with a narrow size distribution could be obtained. The [BMIM][Tf2N] ionic liquid showed no degradation based on the TGA and FT-IR study. The solvent-recyclable process of making size-controlled nanoparticles should have a broad impact on the application of imidazolium-based ionic liquids in the synthesis of nanomaterials. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
25. POLYMERIC CORE-SHELL NANOPARTICLES FOR THERAPEUTICS.
- Author
-
Yi-Yan Yang, Yong Wang, Powell, Ross, and Chan, Peggy
- Subjects
- *
ADDITION polymerization , *DRUG delivery systems , *POLYMERIC composites , *NANOPARTICLES , *PEPTIDES - Abstract
1. Nanobiotechnologies have recently attracted significant attention from chemists, biologists, engineers and pharmaceutical scientists. In particular, they have been widely applied to improve drug, protein/peptide and gene delivery. 2. This review presents recent advances in the field of drug, protein/peptide and gene delivery using natural and synthetic polymer nanoparticles and explains how polymeric nanoparticles are specifically designed to suit the needs for targeted delivery of small molecular drugs, proteins/peptides and genes. In addition, some of the challenges and prospects for these technologies are discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2006
- Full Text
- View/download PDF
26. PREPARATION OF VANADIUM CATALYST CONTAINING NANO-V2O5 PARTICLES.
- Author
-
Wei Wang, Jiacheng Gao, Yong Wang, and Jian Zhou
- Subjects
VANADIUM ,CATALYSTS ,NANOPARTICLES ,NANOSTRUCTURES ,CHEMICAL inhibitors ,CATALYSIS - Abstract
A new preparation process of the vanadium catalyst with nano-V
2 O5 particles was introduced in this paper. The inorganic sol-gel method is used to prepare the sols and gels with p nano-V2 O5 particles. The morphology, size and distribution of the nano-V2 O5 particles in the sols-gels and vanadium catalyst had been studied by TEM, SEM, XRD and DSC. The results show that with the w/v (the ratio of water and vanadium) declining, the morphology of the nano-V2 O5 particles varies from needle to near-ball then to sphere; the better process parameter to prepare the sols and gels with nano-V2 O5 particles is 800~860°C×10~15min; the sols and gels and catalyst with 30~60nm V2 O5 particles had been obtained by this process. [ABSTRACT FROM AUTHOR]- Published
- 2005
- Full Text
- View/download PDF
27. NiO nanoparticles, an algorithm of their biosynthesis, toxicity, and biomedical activities.
- Author
-
K., Velsankar, K., Aravinth, Yong, Wang, S., Mohandoss, Yong, Rok Lee, and Paiva-Santos, Ana Cláudia
- Subjects
- *
BIOSYNTHESIS , *HAZARDOUS substances , *NANOPARTICLE size , *METAL nanoparticles , *NANOPARTICLES , *SURFACE plasmon resonance , *ERYTHROCYTES , *NANOPARTICLES analysis - Abstract
• Polymorphism of formed NiO nanoparticles with size in 25-50 nm was observed. • High toxicity of nanoparticles was witnessed against MG-63 cancer cells. • NiO nanoparticles revealed high biocompatibility on HEK293 normal cells. • Nanoparticles showed bactericidal activity on various human pathogenic bacteria. The green synthesis of metal oxide nanoparticles is interestingly becoming familiar as the reason of its non-toxicity, economical, eco-friendly, and commerciality. The secondary metabolites and bioactive molecules in biomaterial extract play an important role of reducing, capping, stabilizing and chelating activities to form the nanoparticles as a substitute of hazardous chemical surfactants. Hence this present work concentrated on the biogenic synthesis of NiO nanoparticles using grains extract of Oryza longistaminata (red rice), and their toxicity assessment as well as biomedical applications. The synthesized nanoparticles were widely characterized by using several analytical and biomedical techniques. The reduction mechanism of Ni2+ ions using major active phytocompound in red rice grains extract was stated. UV–visible spectroscopic analysis revealed the formation of NiO nanoparticles by emerging the sharp surface Plasmon resonance band at 326 nm. The absorption peaks of red rice grains extract at 206, 260, 330 and 410 nm stated the presence of phytocompounds in them. X-ray diffraction pattern explicated the high crystallinity of NiO nanoparticles and their average crystallite size was found to be at 36 nm. The diffraction pattern of red rice grains revealed the amorphous characteristic. Fourier transform infrared analysis displayed the different vibrational functional groups of nanoparticles and red rice grains. Dynamic light scattering analysis showed the particle size distribution was in between 30-65 nm. High-resolution transmission electron microscopic analysis showed the hexagonal, rectangular, oval and spherical shaped polymorphism of NiO nanoparticles and their size was in 25-50 nm. Energy dispersive X-ray spectrum and mapping analyses validated the formation of NiO nanoparticles by the major existence of Ni and O elements. The high toxicity of nanoparticles towards MG-63 osteosarcoma cancer cells was revealed at 94.69% in 100 μg/mL concentration. The nanoparticles showed no severe toxicity against HEK293 normal cells and red blood cells till higher concentration. The biomedical analyses such as antioxidant, anti-inflammatory and anti-diabetic activities exposed the potential bio-drug activity of NiO nanoparticles with maximum activity of 86.22, 84.23 and 85.18% in the high concentration of 80 μg/mL. The antibacterial activity divulged the good bactericidal drug nature of NiO nanoparticles against both Gram-positive (S. aureus and B. Subtilis) and Gram-negative (S. typhi and K. pneumonia) bacteria with low MBC/MIC ratio. As per the assessment of results, the biosynthesized NiO nanoparticles have non-carcinogenic, high biocompatible and potent nature and it suggests that they can be used as therapeutic candidates in biomedical, clinical and pharmaceutical fields for treating various diseases. [Display omitted] [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
28. Morphological and Electronic Structure of Pt-Re Nanoparticles Supported on Carbon under Activation and Reaction Conditions for Aqueous-Phase Reforming of Bioliquid.
- Author
-
Liang Zhang, Xia, Gordon, Yong Yang, Heldebrant, David, King, David, Yong Wang, and Allard, Lawrence F.
- Subjects
NANOPARTICLES - Abstract
Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010. [ABSTRACT FROM PUBLISHER]
- Published
- 2010
- Full Text
- View/download PDF
29. Measuring Ensemble-Averaged Surface-Enhanced Raman Scattering in the Hotspots of Colloidal Nanoparticle Dimers and Trimers.
- Author
-
Gang Chen, Yong Wang, Miaoxin Yang, Jun Xu, Sook Jin Goh, Ming Pan, and Hongyu Chen
- Subjects
- *
SURFACE enhanced Raman effect , *SURFACE chemistry , *LIGHT scattering , *DIMERS , *NANOPARTICLES , *NANOCRYSTALS - Abstract
The article measures the surface-enhanced Raman scattering (SERS) in colloidal nanoparticle dimers and trimers. It notes that SERS is strong in plasmon-coupled metal nanoparticles (NPs) gap. It points out that SERS enhacement factor (EF) relies on the specific hotspot which makes it difficult to compare different nanocluster results.
- Published
- 2010
- Full Text
- View/download PDF
30. High-Purity Separation of Gold Nanoparticle Dimers and Trimers.
- Author
-
Gang Chen, Yong Wang, Li Huey Tan, Miaoxin Yang, Lee Siew Tan, Yuan Chen, and Hongyu Chen
- Subjects
- *
GOLD spectra , *OLIGOMERS , *POLYMER fractionation , *NANOPARTICLES , *SEPARATION (Technology) , *SURFACE chemistry - Abstract
The article focuses on the separation of high-purity gold nanoparticle dimers and trimers. Study shows that CsCl solution's higher density and viscosity may slow down the nanoclusters and enhance sedimentation velocity's relative difference. It points out that its approach offers a fluent separation method without additional inconvenience as the structural intactness is vital for nanoassembly construction.
- Published
- 2009
- Full Text
- View/download PDF
31. Current perspectives and trends in nanoparticle drug delivery systems in breast cancer: bibliometric analysis and review
- Author
-
Sheng Sun, Ye-hui Wang, Xiang Gao, He-yong Wang, Lu Zhang, Na Wang, Chun-mei Li, and Shao-quan Xiong
- Subjects
bibliometrics ,visualization ,breast cancer ,nanoparticle drug delivery systems ,nanoparticles ,Biotechnology ,TP248.13-248.65 - Abstract
The treatment of breast cancer (BC) is a serious challenge due to its heterogeneous nature, multidrug resistance (MDR), and limited therapeutic options. Nanoparticle-based drug delivery systems (NDDSs) represent a promising tool for overcoming toxicity and chemotherapy drug resistance in BC treatment. No bibliometric studies have yet been published on the research landscape of NDDS-based treatment of BC. In this review, we extracted data from 1,752 articles on NDDS-based treatment of BC published between 2012 and 2022 from the Web of Science Core Collection (WOSCC) database. VOSviewer, CiteSpace, and some online platforms were used for bibliometric analysis and visualization. Publication trends were initially observed: in terms of geographical distribution, China and the United States had the most papers on this subject. The highest contributing institution was Sichuan University. In terms of authorship and co-cited authorship, the most prolific author was Yu Zhang. Furthermore, Qiang Zhang and co-workers have made tremendous achievements in the field of NDDS-based BC treatment. The article titled “Nanomedicine in cancer therapy: challenges, opportunities, and clinical applications” had the most citations. The Journal of Controlled Release was one of the most active publishers in the field. “Global cancer statistics 2018: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries” was the most cited reference. We also analysed “hot” and cutting-edge research for NDDSs in BC treatment. There were nine topic clusters: “tumour microenvironment,” “nanoparticles (drug delivery),” “breast cancer/triple-negative breast cancer,” “combination therapy,” “drug release (pathway),” “multidrug resistance,” “recent advance,” “targeted drug delivery”, and “cancer nanomedicine.” We also reviewed the core themes of research. In summary, this article reviewed the application of NDDSs in the treatment of BC.
- Published
- 2023
- Full Text
- View/download PDF
32. Antiphotocorrosive photocatalysts containing CdS nanoparticles and exfoliated TiO2 nanosheets.
- Author
-
Xiaoxia Yan, Gang Liu, Lianzhou Wang, Yong Wang, Xianfang Zhu, Jin Zou, and Gao Qing (Max) Lu
- Subjects
LIGHTING ,CORROSION & anti-corrosives ,NANOPARTICLES ,X-ray diffraction ,SPECTRUM analysis - Abstract
Aimed at designing an efficient visible light active photocatalyst and suppressing the self-corrosion tendency of CdS nanoparticles, a novel composite consisting of CdS nanoparticles and exfoliated two-dimensional (2D) TiO
2 nanosheets was successfully fabricated using a simple self-assembly process. The prepared samples were characterized using various techniques including x-ray diffraction, ultraviolet-visible absorption spectroscopy, x-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. It was found that the exfoliated 2D nanosheets played an important role as an ultrathin coating to suppress the photocorrosion of CdS nanoparticles, evidenced by inductively coupled plasma-atomic emission spectrometer analysis. The resultant CdS/TiO2 composites exhibited enhanced photocatalytic activity in the oxidation of Rhodamine B in water under visible light irradiation (? > 420 nm). [ABSTRACT FROM AUTHOR]- Published
- 2010
- Full Text
- View/download PDF
33. Efficient Delivery of Bcl-2-Targeted siRNA Using Cationic Polymer Nanoparticles: Downregulating mRNA Expression Level and Sensitizing Cancer Cells to Anticancer Drug.
- Author
-
Cyrus W. Beh, Wei Yang Seow, Yong Wang, Ying Zhang, Zhan Yuin Ong, Pui Lai Rachel Ee, and Yi-Yan Yang
- Subjects
- *
MEDICAL polymers , *NANOPARTICLES , *SMALL interfering RNA , *ANTINEOPLASTIC agents , *CANCER cells , *GENETIC regulation , *MESSENGER RNA - Abstract
In this study, cationic nanoparticles self-assembled from the amphiphilic copolymer poly(N-methyldietheneamine sebacate)-co-[(cholesteryl oxocarbonylamido ethyl) methyl bis(ethylene) ammonium bromide] sebacate) (P(MDS-co-CES) were synthesized and used to deliver Bcl-2 targeted siRNA into HepG2, HeLa and MDA-MB-231 cell lines, and downregulate Bcl-2 mRNA expression levels. Confocal microscopic studies show that the nanoparticles were able to complex with siRNA and deliver it inside the cells efficiently, but siRNA was easily dissociated from the complexes in the cytoplasm for its biological functions. Bcl-2 mRNA expression levels as low as 10% were achieved after treatment with nanoparticle/siRNA complexes. The downregulation efficiency of Bcl-2 mRNA level was similar to that mediated by Lipofectamine but higher than that induced by PEI. PEG was also conjugated to siRNA via a cleavable disulfide bond, and nanoparticle/siRNA-PEG complexes showed no significant protein adsorption as compared with 26 and 17% for blank nanoparticles and nanoparticle/siRNA complexes, respectively. The presence of serum caused slight aggregation of nanoparticle/siRNA or nanoparticle/siRNA-PEG complexes. However, the size of the complexes was still below 250 nm after being incubated in PBS containing 10% serum for 4 h. On the other hand, PEGylated siRNA delivered by the nanoparticles downregulated Bcl-2 mRNA expression level in the cells as efficiently as unmodified siRNA. Bcl-2 protein was also downregulated efficiently by nanoparticle/siRNA complexes in all cell lines tested. The downregulation of Bcl-2 mRNA or Bcl-2 protein did not show significant cell death in the tested siRNA and polymer concentration range. However, the delivery of siRNA sensitized HeLa cells to paclitaxel treatment, yielding significant improvement over the untreated cells (p< 0.05). These cationic nanoparticles may be potentially employed to downregulate Bcl-2 expression and sensitize cancer cells to anticancer drugs for more efficient chemotherapy. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
34. The structure–activity relationship of Fe nanoparticles in CO adsorption and dissociation by reactive molecular dynamics simulations.
- Author
-
Lu, Kuan, Huo, Chun-Fang, He, Yurong, Guo, Wen-Ping, Peng, Qing, Yang, Yong, Li, Yong-Wang, and Wen, Xiao-Dong
- Subjects
- *
STRUCTURE-activity relationships , *NANOPARTICLES , *ADSORPTION (Chemistry) , *CARBURIZATION , *MOLECULAR dynamics , *ATOMS - Abstract
• The structure–activity relationship of Fe nanoparticles in the CO activation process was investigated. • Structures includes four aspects: morphologies, sizes, defects, and hetero atoms. • Line dislocation and vacancies suggest an effective way to tune the CO dissociation rate. • CO 2 formation: Eley–Rideal vs. Langmuir–Hinshelwood mechanism. The structure–activity relationship is crucial in catalytic performance and material design but still largely obscure due to the complexity of heterogeneous catalytic systems. CO activation occurs widely in Fischer–Tropsch reactions and pyrometallurgy, and it is a key to understanding carburization. Here, we investigate the structure–activity relationship in Fe nanoparticles by reactive molecular dynamics simulations. We focus on two activities, the adsorption and dissociation of CO, and four structural characteristics, morphologies, sizes, defects, and heteroatoms. The results show that CO adsorption and dissociation varies with the change of nanoparticles. Line dislocation and vacancies can strikingly boost CO dissociation, suggesting an effective way to tune the CO dissociation rate. Further analysis shows that the Eley–Rideal mechanism possibly works in the early periods, followed by the Langmuir–Hinshelwood mechanism in the later periods for CO 2 formation. Our results shed light on the mechanism and possible optimization of the carburization of iron. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
35. Nanoparticles Incorporated inside Single-Crystals: Enhanced Fluorescent Properties.
- Author
-
Yujing Liu, Huidong Zang, Ling Wang, Weifei Fu, Wentao Yuan, Jiake Wu, Xinyi Jin, Jishu Han, Changfeng Wu, Yong Wang, Xin, Huolin L., Hongzheng Chen, and Hanying Li
- Subjects
- *
SINGLE crystals , *QUANTUM dots , *CALCITE , *AGAROSE , *NANOPARTICLES - Abstract
Incorporation of guest materials inside single-crystalline hosts leads to single-crystal composites that have become more and more frequently seen in both biogenic and synthetic crystals. The unique composite structure together with long-range ordering promises special properties that are, however, less often demonstrated. Here, we examine the fluorescent properties of quantum dots (QDs) and polymer dots (Pdots) encapsulated inside the hosts of calcite single-crystals. Two CdTe QDs and two Pdots are incorporated into growing calcite crystals, as the QDs and Pdots are dispersed in the crystallization media of agarose gels. As a result, enhanced fluorescent properties are obtained from the QDs and Pdots inside calcite single-crystals with greatly improved photostability and significantly prolonged fluorescence lifetime, compared to those in solutions and gels. Particularly, the fluorescence lifetime increases by 0.5-1.6 times after the QDs or Pdots are incorporated. The enhanced fluorescent properties indicate the advantages of encapsulation by single-crystal hosts that provide dense shells to isolate the fluorescent nanoparticles from atmosphere. As such, this work has implications for advancing the research of single-crystal composites toward their functional design. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
36. Effect of SiO2 Nanoparticles on Wax Crystallization and Flow Behavior of Model Crude Oil.
- Author
-
Xin Song, Hongyao Yin, Yujun Feng, Sheng Zhang, and Yong Wang
- Subjects
- *
CRYSTALLIZATION , *NANOPARTICLES , *WAXES , *PETROLEUM , *ASPHALTENE analysis , *PETROLEUM transportation - Abstract
In oil industry, wax deposition is one of the frequently encountered problems that causes severe issues during the production, storage, and transportation of crude oil. Recently, it is found that addition of nanohybrids to crude oil is an effective method to solve this problem. However, the mechanism of how nanoparticles affect the wax crystallization and rheological behavior of crude oil has not been clearly understood. Here we reported the influence of SiO2 nanoparticles on crystallization and rheological behavior of model oils with and without asphaltene and resin. It was demonstrated that the wax appearance temperature increased upon the addition of SiO2 nanoparticles of model oil without asphaltenes and resin, while the rheological behavior was less affected. When in the presence of asphaltenes and resin, the amount of wax crystals, wax appearance temperature, and rheological parameter of model oils were found to decrease while SiO2 nanofluid was added, resulting in the improvement of flowability. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
37. Molybdenum-Carbide-Modified Nitrogen-Doped Carbon Vesicle Encapsulating Nickel Nanoparticles: A Highly Efficient, Low-Cost Catalyst for Hydrogen Evolution Reaction.
- Author
-
Shiping Wang, Jing Wang, Minglei Zhu, Xiaobing Bao, Bingyang Xiao, Diefeng Su, Haoran Li, and Yong Wang
- Subjects
- *
HYDROGEN evolution reactions , *METAL catalysts , *MOLYBDENUM compounds , *CARBIDES , *NITROGEN compounds , *NANOPARTICLES - Abstract
Despite being promising substitutes for noble metal catalysts used in hydrogen evolution reaction (HER), the nonprecious metal catalysts (NPMCs) based on inexpensive and earth-abundant 3d transition metals (TMs) are still practically unfeasible due mainly to unsatisfactory activity and durability. Herein, a highly active and stable catalyst for HER has been developed on the basis of molybdenum-carbide-modified N-doped carbon vesicle encapsulating Ni nanoparticles (MoxC-Ni@NCV). This Mox-CN@NCV material was synthesized simply by the solid-state thermolysis of melamine-related composites of oxalate and molybdate with uniform Ni ions doping (Ni@MOM-com). Notably, the prepared MoxC-Ni@NCV was almost the most efficient NPMCs for HER in acidic electrolyte to date. Besides good long-term stability, MoxC-Ni(o)NCV exhibited a quiet low overpotential that was comparable to Pt/C. Thus, this work opens a new avenue toward the development of highly efficient, inexpensive HER catalysts. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
38. Long-Circulating lodinated Albumin-Gadolinium Nanoparticles as Enhanced Magnetic Resonance and Computed Tomography Imaging Probes for Osteosarcoma Visualization.
- Author
-
Qianliang Wang, Ling Lv, Zhuoyan Ling, Yangyun Wang, Yujing Liu, Liubing Li, Guodong Liu, Liqin Shen, Jun Yan, and Yong Wang
- Subjects
- *
ALBUMINS , *GADOLINIUM , *NANOPARTICLES , *MAGNETIC resonance , *COMPUTED tomography , *NANOSTRUCTURED materials , *OSTEOSARCOMA , *DIAGNOSIS - Abstract
Multimodal imaging probes represent an extraordinary tool for accurate diagnosis of diseases due to the complementary advantages of multiple imaging modalities. The purpose of the work was to fabricate a simple dual-modality MR/CT probe for osteosarcoma visualization in vivo. Protein-directed synthesis methods offer a suitable alternative to MR/CT probe produced by synthetic chemistry. Bovine serum albumin (BSA) bound to gadolinium nanoparticles (GdNPs) was first prepared via a biomimetic synthesis method and was subsequently iodinated by chloramine-T method. The final iodinated BSA-GdNPs (1-BSA-GdNPs) showed excellent chemical stability and biocompatibility, intense X-ray attenuation coefficient, and good MR imaging ability. However, an iodinated protein nanoparticles synthesis for MR/CT imaging, as well as its useful application, has not been reported yet. Intravenous injection of I-BSA-GdNPs into orthotopic osteosarcoma-bearing rats led to its accumulation and retention by the tumor, allowing for a noninvasive tumor dual-modality imaging through the intact thigh. The long-circulating dual-model I-BSA-GdNPs probes possess potential application for image-guided drug delivery and image-guided surgery. Our study is therefore highlighting the properties of albumin in this field combined with its useful use in dual-model MR/CT osteosarcoma visualization, underlining its potential use as a drug carrier for a future therapy on cancer. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
39. Theoretical study about adsorbed oxygen reduction over χ-Fe5C2: formation of H2O and CO2.
- Author
-
Bai, Ya, Liu, Jinjia, Wang, Tao, Song, Yu-Fei, Yang, Yong, Li, Yong-Wang, and Wen, Xiaodong
- Subjects
- *
OXYGEN reduction , *CHEMICAL reduction , *NANOPARTICLES , *CATALYSIS , *PHYSICAL & theoretical chemistry - Abstract
• The mechanism for eliminating adsorbed oxygen by the reduction with H and CO on χ-Fe 5 C 2 surfaces was investigated. • The removal mechanism shows diversity over different facets. • Carbon-rich surface exhibits higher barriers to direct CO 2 formation, like (110) and (111). The removal of surface oxygen adsorbed on iron carbides is essential to protect the nanoparticle from oxidation in heterogeneous catalysis. Herein, we explored the removal of pre-adsorbed oxygen on seven facets of χ-Fe 5 C 2, and four pathways including both direct and indirect routes for generating H 2 O and CO 2 were investigated. The removal mechanism shows diversity over different facets. On (010), the formation of CO 2 through the reaction between surface oxygen and adsorbed CO is more favorable. While on (510), (001), (110), (11-1) and (-411), the elimination in the form of H 2 O through OH disproportionation dominates. In particular, surface oxygen can be removed facilely either in H 2 O or CO 2 on (111) surface. What's more, surface with more carbons exhibits higher barriers to direct CO 2 formation, like (110) and (111). Our work provides knowledge about mechanism of O removal and CO 2 formation, which may be helpful in protecting the nanoparticle from further oxidation. Graphical Abstract [Display omitted]. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
40. Synthesis of Palladium Nanoparticles Supported on Mesoporous N-Doped Carbon and Their Catalytic Ability for Biofuel Upgrade.
- Author
-
Xuan Xu, Yi Li, Yutong Gong, Pengfei Zhang, Haoran Li, and Yong Wang
- Subjects
- *
PALLADIUM , *NANOPARTICLES , *CARBON , *MESOPOROUS materials , *SEMICONDUCTOR doping , *BIOMASS energy , *VANILLIN - Abstract
We report a catalyst made of Pd nanoparticles (NPs) supported on mesoporous N-doped carbon, Pd@CN0132, which was shown to be highly active in promoting biomass refining. The use of a task-specific ionic liquid (3-methyl-1-butylpyridine dicyanamide) as a precursor and silica NPs as a hard template afforded a high-nitrogen-content (12 wt %) mesoporous carbon material that showed high activity in stabilizing Pd NPs. The resulting Pd@CN0.132 catalyst showed very high catalytic activity in hydrodeoxygenation of vanillin (a typical model compound of lignin) at low H2 pressure under mild conditions in aqueous media. Excellent catalytic results (100% conversion of vanillin and 100% selectivity for 2-methoxy-4-methylphenol) were achieved, and no loss of catalytic activity was observed after six recycles. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
41. Stabilization of Metal Nanoparticles in Cubic Mesostructured Silica and Its Application in Regenerable Deep Desulfurization of Warm Syngas.
- Author
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Liyu Li, David L. King, Jun Liu, Qisheng Huo, Kake Zhu, Chongmin Wang, Mark Gerber, Don Stevens, and Yong Wang
- Subjects
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NANOPARTICLES , *SILICA , *DESULFURIZATION , *SYNTHESIS gas , *METALLIC oxides , *SURFACE area , *POLLUTION control industry , *COPPER-nickel alloys - Abstract
Metal and metal oxide nanoparticles supported on high surface area materials are widely used in industry for fuel and chemical production and for environmental pollution control, but preventing nanosized particle sintering has remained a great challenge. In this paper, we report that Ni−Cu alloy nanoparticles can be effectively stabilized in cubic mesostructured silica (SBA-16) following a conventional impregnation and thermal treatment process. The three-dimensional interconnected cage structure of the mesoporous SBA-16 allows good accessibility of reactant gas molecules to the metal nanoparticles and confines these particles within its nanosized cages. This confinement hinders metal nanoparticle migration and sintering under harsh conditions. A new class of regenerable metal-based adsorbents which can remove sulfur impurities from warm syngas stream down to less than 60 parts per billion by volume (ppbv) is described. This same confinement strategy is expected to have impact for minimizing sintering or particle coarsening of nanosized materials employed in other applications. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
42. Characterization of Dispersed Heteropoly Acid on Mesoporous Zeolite Using Solid-State 31P NMR Spin-Lattice Relaxation.
- Author
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Kake Zhu, Jianzhi Hu, Xiaoyan She, Jun Liu, Zimin Nie, Yong Wang, Peden, Charles H. F., and Ja Hun Kwak
- Subjects
- *
HETEROCHAIN polymers , *CATALYSTS , *CATALYSIS , *CHEMICAL inhibitors , *ZEOLITE absorption & adsorption , *NANOPARTICLES - Abstract
Dispersion and quantitative characterization of supported catalysts is a grand challenge in catalytic science. In this paper, heteropoly acid H3PW12O40 (HPA) is dispersed on mesoporous zeolite silicalite-1 derived from hydrothermal synthesis using carbon black nanoparticle templates, and the catalytic activity is studied for 1-butene isomerization. The HPAs supported on conventional zeolite and on mesoporous zeolite exhibit very different activities and thus provide good model systems to investigate the structure dependence of the catalytic properties. The HPA on mesoporous silicalite-1 shows enhanced catalytic activity for 1 -butene isomerization, while HPA on conventional silicalite-1 exhibits low activity. To elucidate the structural difference, supported HPA catalysts are characterized using a variety of techniques, including 31P magic angle spinning nuclear magnetic resonance, and are shown to contain a range of species on both mesoporous and conventional zeolites. However, contrary to studies reported in the literature, conventional NMR techniques and chemical shifts alone do not provide sufficient information to distinguish the dispersed and aggregated surface species. The dispersed phase and the nondispersed phase can only be unambiguously and quantitatively characterized using spin-lattice relaxation NMR techniques. The HPA supported on mesoporous zeolite contains a fast relaxation component related to the dispersed catalyst, giving a much higher activity, while the HPA supported on conventional zeolite has essentially only the slow relaxation component with very low activity. The results obtained from this work demonstrate that the combination of spinning sideband fitting and spin-lattice relaxation techniques can provide detailed structural information on not only the Keggin structure for HPA but also the degree of dispersion on the support. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
43. Sequential Electrochemical Oxidation and Site-Selective Growth of Nanoparticles onto AFM Probes.
- Author
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Haitao Wang, Tian Tian, Yong Zhang, Zhiqiang Pan, Yong Wang, and Zhongdang Xiao
- Subjects
- *
ATOMIC force microscopy , *MOLECULAR probes , *CHLOROSILANES , *NANOPARTICLES , *ELECTROCHEMISTRY , *OXIDATION , *CHEMICAL vapor deposition - Abstract
In this work, we reported an approach for the site-selective growth of nanoparticle onto the tip apex of an atomic force microscopy (AFM) probe. The silicon AFM probe was first coated with a self-assembled monolayer (SAM) of octadecyltrichlorosilane (OTS) through a chemical vapor deposition (CVD) method. Subsequently, COOH groups were selectively generated at the tip apex of silicon AFM probes by applying an appropriate bias voltage between the tip and a flat gold electrode. The transformation of methyl to carboxylic groups at the tip apex of the AFM probe was investigated through measuring the capillary force before and after electrochemical oxidation. To prepare the nanoparticle terminated AFM probe, the oxidized AFM probe was then immersed in an aqueous solution containing positive metal ions, for example, Ag +, to bind positive metal ions to the oxidized area (COOH terminated area), followed by chemical reduction with aqueous NaBH 4and further development (if desired) to give a metal nanoparticle-modified AFM probe. The formation of a metal nanoparticle at the tip apex of the AFM probe was confirmed by scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDXA). [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
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