8 results on '"Zhao, Wuduo"'
Search Results
2. Self-Assembled Hexagonal Superparamagnetic Cone Structures for Fabrication of Cell Cluster Arrays
- Author
-
Zhenyu Huang, Yangjie Cao, Zon-Han Wei, Chen Yinling, Hu Zhixin, Zhao Wuduo, Weijen Chang, Chaojun Gao, Xiaoxi Liu, Yenya Hsu, Zhou Kejia, Zhao Dongyang, and Yang Xiaonan
- Subjects
Ferrofluid ,Materials science ,Fabrication ,genetic structures ,Cell Culture Techniques ,02 engineering and technology ,Substrate (electronics) ,Surface tension ,03 medical and health sciences ,chemistry.chemical_compound ,Cell Movement ,Cell Line, Tumor ,Humans ,General Materials Science ,Colloids ,Dimethylpolysiloxanes ,030304 developmental biology ,0303 health sciences ,Condensed matter physics ,Polydimethylsiloxane ,Magnetic Phenomena ,Water ,equipment and supplies ,021001 nanoscience & nanotechnology ,Magnetic field ,chemistry ,Magnetic nanoparticles ,Polystyrenes ,Magnetic Iron Oxide Nanoparticles ,sense organs ,0210 nano-technology ,human activities ,Superparamagnetism - Abstract
In this study, we demonstrated that arrays of cell clusters can be fabricated by self-assembled hexagonal superparamagnetic cone structures. When a strong out-of-plane magnetic field was applied to the ferrofluid on a glass substrate, it will induce the magnetic poles on the upper/lower surfaces of the continuous ferrofluid to increase the magnetostatic energy. The ferrofluid will then experience hydrodynamic instability and be split into small droplets with cone structures because of the compromising surface tension energy and magnetostatic energy to minimize the system's total energy. Furthermore, the ferrofluid cones were orderly self-assembled into hexagonal arrays to reach the lowest energy state. After dehydration of these liquid cones to form solid cones, polydimethylsiloxane was cast to fix the arrangement of hexagonal superparamagnetic cone structures and prevent the leakage of magnetic nanoparticles. The U-343 human neuronal glioblastoma cells were labeled with magnetic nanoparticles through endocytosis in co-culture with a ferrofluid. The number of magnetic nanoparticles internalized was (4.2 ± 0.84) × 106 per cell by the cell magnetophoresis analysis. These magnetically labeled cells were attracted and captured by hexagonal superparamagnetic cone structures to form cell cluster arrays. As a function of the solid cone size, the number of cells captured by each hexagonal superparamagnetic cone structure was increased from 48 to 126 under a 2000 G out-of-plane magnetic field. The local magnetic field gradient of the hexagonal superparamagnetic cone was 117.0-140.9 G/mm from the cell magnetophoresis. When an external magnetic field was applied, we observed that the number of protrusions of the cell edge decreased from the fluorescence images. It showed that the local magnetic field gradient caused by the hexagonal superparamagnetic cones restricted the cell growth and migration.
- Published
- 2021
3. Rapid determination of acrolein and crotonaldehyde in tobacco smoke with water-assisted APCI-MS/MS
- Author
-
Zhao Wuduo, Shusheng Zhang, Fan Wu, Xiankuan Huo, Yong-Li Zong, Junhui Liu, Wang Dingzhong, Binbin Lu, and Jian-Xun Zhang
- Subjects
Chromatography ,010401 analytical chemistry ,Acrolein ,Atmospheric-pressure chemical ionization ,010402 general chemistry ,Condensed Matter Physics ,Tandem mass spectrometry ,01 natural sciences ,0104 chemical sciences ,Solvent ,chemistry.chemical_compound ,chemistry ,Linear range ,Water cluster ,Physical and Theoretical Chemistry ,Crotonaldehyde ,Derivatization ,Instrumentation ,Spectroscopy - Abstract
The methods most frequently used in the aldehyde detection were based on derivatization reactions with disadvantage of time-consuming. In this study, a method was developed to rapidly detect acrolein and crotonaldehyde by a water-assisted atmospheric pressure chemical ionization tandem mass spectrometry (APCI-MS/MS). With the addition of water, solvent ion signal was suppressed due to the formation of protonated water cluster, which benefited for the analysis of spectra. Two orders of linear range were obtained in the concentration from 0.01 to 1 μg/L with the addition of water. Finally, this method was successfully applied to detect acrolein and crotonaldehyde in tobacco smoke with analytical period less than four minutes. The experimental results indicate that the developed method has the potential application in environmental monitoring of acrolein and crotonaldehyde.
- Published
- 2016
4. Direct Analysis of Carbonyl Compounds by Mass Spectrometry with Double-Region Atmospheric Pressure Chemical Ionization
- Author
-
Zhao Wuduo, Shihao Sun, Jianxun Zhang, Hongtu Zhang, Guobi Chai, Wang Dingzhong, Yihan Zhang, Binbin Lu, and Qidong Zhang
- Subjects
Male ,Analytical chemistry ,Atmospheric-pressure chemical ionization ,010402 general chemistry ,Mass spectrometry ,01 natural sciences ,Mass Spectrometry ,Analytical Chemistry ,Ion ,chemistry.chemical_compound ,Fragmentation (mass spectrometry) ,Limit of Detection ,Ionization ,Animals ,Humans ,Aldehydes ,Volatile Organic Compounds ,Atmospheric pressure ,Cyclohexanones ,010401 analytical chemistry ,Smoking ,Ion source ,0104 chemical sciences ,Heptanal ,Atmospheric Pressure ,Milk ,chemistry ,Breath Tests ,Exhalation ,Biomarkers - Abstract
Direct analysis of highly reactive volatile species such as the aliphatic aldehydes as vital biomarkers remains a great challenge due to difficulties in the sample pretreatment. To address such a challenge, we herein report the development of a novel double-region atmospheric pressure chemical ionization mass spectrometry (DRAPCI-MS) method. The DRAPCI source implements a separated structural design that uses a focus electrode to divide the discharge and ionization region to reduce sample fragmentation in the ionization process. Counterflow introduction (CFI) configuration was adopted in the DRAPCI source to reduce background noise, while ion transmission efficiency was optimized through simulating the voltage of the focus electrode and the ion trajectory of the ion source. The limits of detection (LODs) of four carbonyl compounds cyclohexanone, hexanal, heptanal, and octanal by DRAPCI-MS were between 0.1 and 3 μg·m–3, approximately two to eight times lower than those by atmospheric pressure chemical ioni...
- Published
- 2019
5. Localization of cells using magnetized patterned thin films
- Author
-
H.T. Huang, Z.H. Wei, X.Z. Xu, J.J. Liou, and Zhao Wuduo
- Subjects
Square tiling ,Materials science ,Condensed matter physics ,Diagonal ,Bioengineering ,02 engineering and technology ,Substrate (electronics) ,equipment and supplies ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Ferric Compounds ,01 natural sciences ,Square (algebra) ,Intersection (Euclidean geometry) ,0104 chemical sciences ,Magnetic field ,Biomaterials ,Magnetics ,Domain wall (magnetism) ,Mechanics of Materials ,Magnets ,Nanoparticles ,Thin film ,0210 nano-technology ,human activities - Abstract
In this study, the nasopharyngeal carcinoma cell line was cultured in a superparamagnetic iron oxide nanoparticle aqueous solution with a concentration of 1 μg/mL by using magnetic labeling technology. The cells took up superparamagnetic nanoparticles through the endocytosis process, which caused the cells to become magnetic and manipulable by a magnetic field gradient. Each cell contained 5.266 × 106 superparamagnetic nanoparticles, as determined using the magnetophoresis method. A specific domain configuration and its related distribution of magnetic poles in a patterned thin film were obtained after applying a magnetic field in a specific direction. Here, patterned magnetic thin films were designed to form square grid and square ring structures. When the magnetic field of 3000 G was applied along the diagonal of the square (45° direction) and then released, magnetic cells were trapped at the intersection of the square grid and the 45° diagonal corner of the square ring structure. From micromagnetic simulation results, it was determined that head-to-head and tail-to-tail domain walls with a high magnetic pole density formed at the corners of the square ring structure in the 45° diagonal direction, and the attractive force between a head-to-head/tail-to-tail domain wall and a cell at a height of 1 μm above the corner was approximately 2.055 × 10−10 N. In the square grid case, the attractive force between the domain wall at the intersection and a cell at a height of 1 μm above the intersection was approximately 2.245 × 10−10 N. The results of this study demonstrated that cells can simultaneously be arranged at designated locations physically by using patterned magnetic thin films in a noninvasive manner without chemical modification of the substrate.
- Published
- 2019
6. Long-Term Real-Time Monitoring Catalytic Synthesis of Ammonia in a Microreactor by VUV-Lamp-Based Charge-Transfer Ionization Time-of-Flight Mass Spectrometry
- Author
-
Lei Hua, Wendong Chen, Ping Chen, Zhao Wuduo, Haiyang Li, Bangyu Ju, Yuanyuan Xie, and Keyong Hou
- Subjects
Ammonia production ,Ion beam deposition ,Chemistry ,Ionization ,Reagent ,Analytical chemistry ,Microreactor ,Mass spectrometry ,Ion source ,Analytical Chemistry ,Ion - Abstract
With respect to massive consumption of ammonia and rigorous industrial synthesis conditions, many studies have been devoted to investigating more environmentally benign catalysts for ammonia synthesis under moderate conditions. However, traditional methods for analysis of synthesized ammonia (e.g., off-line ion chromatography (IC) and chemical titration) suffer from poor sensitivity, low time resolution, and sample manipulations. In this work, charge-transfer ionization (CTI) with O2(+) as the reagent ion based on a vacuum ultraviolet (VUV) lamp in a time-of-flight mass spectrometer (CTI-TOFMS) has been applied for real-time monitoring of the ammonia synthesis in a microreactor. For the necessity of long-term stable monitoring, a self-adjustment algorithm for stabilizing O2(+) ion intensity was developed to automatically compensate the attenuation of the O2(+) ion yield in the ion source as a result of the oxidation of the photoelectric electrode and contamination on the MgF2 window of the VUV lamp. A wide linear calibration curve in the concentration range of 0.2-1000 ppmv with a correlation coefficient (R(2)) of 0.9986 was achieved, and the limit of quantification (LOQ) for NH3 was in ppbv. Microcatalytic synthesis of ammonia with three catalysts prepared by transition-metal/carbon nanotubes was tested, and the rapid changes of NH3 conversion rates with the reaction temperatures were quantitatively measured with a time resolution of 30 s. The high-time-resolution CTI-TOFMS could not only achieve the equilibrium conversion rates of NH3 rapidly but also monitor the activity variations with respect to investigated catalysts during ammonia synthesis reactions.
- Published
- 2014
7. Quasi-Trapping Chemical Ionization Source Based on a Commercial VUV Lamp for Time-of-Flight Mass Spectrometry
- Author
-
Haiyang Li, Keyong Hou, Chuang Chen, Yuanyuan Xie, Ping Chen, Lei Hua, Zhao Wuduo, and Wendong Chen
- Subjects
Chemical ionization ,Chemistry ,Ionization ,Analytical chemistry ,Thermal ionization ,Atomic physics ,Mass spectrometry ,Electron ionization ,Ion source ,Analytical Chemistry ,Ambient ionization ,Atmospheric-pressure laser ionization - Abstract
The application of VUV lamp-based single photon ionization (SPI) was limited due to low photon energy and poor photon flux density. In this work, we designed a quasi-trapping chemical ionization (QT-CI) source with a commercial VUV 10.6 eV krypton lamp for time-of-flight mass spectrometry. The three electrode configuration ion source with RF voltage on the second electrode constitutes a quasi-trapping region, which has two features: accelerating the photoelectrons originated from the photoelectric effect with VUV light to trigger the chemical ionization through ion-molecule reaction and increasing the collisions between reactant ion O2(+) and analyte molecules to enhance the efficiency of chemical ionization. Compared to single SPI based on VUV krypton lamp, the QT-CI ion source not only apparently improved the sensitivity (e.g., 12-118 fold enhancement were achieved for 13 molecules, including aromatic hydrocarbon, chlorinated hydrocarbon, hydrogen sulfide, etc.) but also extended the range of ionizable molecules with ionization potential (IP) higher than 10.6 eV, such as propane, dichloroethane, and trichloromethane.
- Published
- 2014
8. On-line Analysis of Flavor Compounds in Toothpastes by Single Photon Ionization Mass Spectrometry
- Author
-
Wendong Chen, Zhao Wuduo, Hua Lei, Ping Chen, Keyong Hou, Li Hai-Yang, Jing-Hua Li, Huapeng Cui, and Yuanyuan Xie
- Subjects
Photon ,Chemistry ,Analytical chemistry ,General Medicine ,Ionization mass spectrometry ,Flavor ,Line (formation) - Published
- 2013
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.