Food & Function
·
2016
·Vol. 8
·期 1
·122-131
·
IF 2.686
Da Ma,Zong-Cai Tu,Hui Wang,Lu Zhang,Na He,David Julian McClements
Tyrosinase is an enzyme that promotes enzymatic browning of fruits and vegetables, thereby reducing product quality. A variety of analytical tools were used to characterize the interactions between tyrosinase and a natural tyrosinase inhibitor (glycolic acid). Hydrogen/deuterium exchange coupling with mass spectrometry (HDX-MS) was used to elucidate the interaction mechanism between glycolic acid and tyrosinase. UV-visible, fluorescence and circular dichroism spectroscopy analysis indicated that glycolic acid inhibited tyrosinase activity in a mixed-type manner with an IC50 of 83 ± 14 μM. The results of these techniques suggested that glycolic acid bound to tyrosinase through hydrophobic attraction, and this interaction led to a pronounced conformational change of the enzyme molecules. HDX-MS analysis showed that the activity of tyrosinase was primarily inhibited by a structural perturbation of its active site (His 263). This study provides a comprehensive understanding of the interaction between glycolic acid and tyrosinase, which could lead to new approaches to control tyrosinase activity in foods and other products.
研究领域:
食品科学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Zhongyang Zheng,Heping Li,Fangjian Li,Liyu Zheng,Shenming Yin,Xinyun Wang,Youwei Yan
Two-dimensional materials, impermeable to various mediums, have ignited the great interest in developing multifunction nanocomposite coatings. Even though Al 2 O 3 has excellent thermal and chemical stability, it is hard to obtain Al 2 O 3 nanosheets from their non-lamellar structured bulk counterparts. In this work, we have developed a bottom–up strategy to synthesize several-nanometer thick Al 2 O 3 nanosheets by taking graphene oxide as the templates, and further improved their dispersibility by modifying them with poly-dopamine (PDA). These PDA-modified Al 2 O 3 nanosheets were then successfully integrated into the nanosized ZrO 2 coating to enhance its anti-corrosion and gas permeation reduction properties. With the Al 2 O 3 nanosheets inserted, corrosion resistance and deuterium resistance of the ZrO 2 coating were increased by 1000% and 1557%, respectively, both of which were above two orders of magnitude higher than that of the 321 steel substrate. The significant improvements achieved by Al 2 O 3 nanosheets demonstrate their capacity to effectively block the diffusion of both ions and deuterium atoms. This work not only offers a new platform for fabricating nanosheets from non-lamellar structured materials, but also indicates tremendous potential of Al 2 O 3 nanosheets as a novel filler for developing high-performance functional coatings.
研究领域:
材料科学
·
表面工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NUCLEAR MATERIALS
·
2025
·
IF 3.2
Guangfan Tan,Qilai Zhou,Yasuhisa Oya,Yingchun Zhang,Chang-An Wang,Yanhao Dong
The Li 2 TiO 3 and Li 2 ZrO 3 ceramic pebbles are regarded as promising tritium breeder on account of their superb chemical stability, high tritium diffusion rates, and neutron multiplication potential of Zr, respectively. To integrate the advantages of these two materials, it is necessary to develop a composite such as Li 2 TiO 3 -Li 2 ZrO 3 , which is ideal for advanced fusion reactor designs. Up to now, fabricated biphasic ceramic pebbles generally suffer from low production yield, inadequate crushing load, and high cost, which restricts their application in practice. In this paper, biphasic Li 2 TiO 3 -Li 2 ZrO 3 tritium breeding pebbles with superior crushing strength are successfully fabricated employing the centrifugal granulation method by selecting the appropriate binder and controlling the growth rate. Moreover, by this technique, ceramic pebbles with wide diameter distribution can be obtained, which will help to improve the packing factor of pebble beds in the solid blanket. In addition, the composition, microstructure, and internal structure of the Li 2 TiO 3 -Li 2 ZrO 3 ceramic pebbles are thoroughly analyzed, respectively. The Li 2 TiO 3 -Li 2 ZrO 3 ceramic pebbles, after being sintered at 1100 °C, attained a high sphericity of 0.97, a superior crushing load of 67.6 N, and an optimum porosity of 9.75 % in the shell. Moreover, the Li 2 TiO 3 -Li 2 ZrO 3 ceramic pebbles also exhibit excellent deuterium release properties with the main form of HDO. The above results show that the centrifugal granulation method is not only applicable to the mass production of Li 2 TiO 3 -Li 2 ZrO 3 ceramic pebbles but also to other tritium breeders, which offers promising prospects for the development of advanced tritium breeding materials in the future.
研究领域:
材料科学
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核工程
·
陶瓷学
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聚变技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LABELLED COMPOUNDS & RADIOPHARMACEUTICALS
·
2025
·
IF 0.9
Jiaojiao Zuo,Jing Kang,Jingjing Hong,Jingwen Li,Yi Fang,Chunyi Liu,Minhao Xie,Zhengping Chen
Dopamine transporter (DAT) is closely associated with neurodegenerative diseases such as Parkinson's disease (PD). To develop an in vivo stable radioligand targeting DAT, we synthesized a novel iodine-131-labeled tropane analog [ 131 I] 1 with deuteration on both the N -fluoropropyl and 2 β -carbomethoxy positions of the tropane scaffold and then biologically compared with the previously reported analog [ 131 I]FP-CIT-d 6 with deuteration only on the N -fluoropropyl group. The radioligand [ 131 I] 1 was obtained via a radioiodine-destannylation reaction with a radiochemical yield of ~95%, a radiochemical purity of > 99% and a molar activity of 12.72 GBq/μmol. [ 131 I] 1 exhibited a high in vitro binding affinity for DAT with an IC 50 value of 2.2 nM. Metabolic stability studies demonstrated that [ 131 I] 1 displayed superior in vivo stability compared with [ 131 I]FP-CIT-d 6 . Biodistribution studies revealed that [ 131 I] 1 had better DAT affinity, specificity, and a higher target-to-background ratio than [ 131 I]FP-CIT-d 6 . Ex vivo autoradiography and blocking experiments validated the selective and reversible binding of [ 131 I] 1 to DAT and superiority to [ 131 I]FP-CIT-d 6 . These preliminary results suggest that deuterated radioligand [ 131 I] 1 , with enhanced in vivo stability and higher target-to-background ratio, is a promising DAT probe, warranting the development and application of 123 I-labeled counterpart ([ 123 I] 1 ) for SPECT imaging in DAT-related disorders.
研究领域:
医学影像学
·
神经生物学
·
放射化学
✓ 已验证
DOI
PubMed
高影响因子
FUEL
·
2024
·
IF 6.7
Xiao-Dong Zhou,Xue-Long Yin,Lang Liu,Xue-Li Huang,Jing-Mei Liu,Ting Liu,He Lin,Feng-Yun Ma
Understanding hydrogen activation is crucial for improving the performance of direct coal liquefaction (DCL) which is essential for the clean, efficient conversion of coal to fuel oils and aromatic chemicals. Three hydrogen sources are involved in DCL: solvent hydrogen (SH), dissolved hydrogen that reacts directly (DHD), and dissolved hydrogen that reacts through a solvent (DHS). Quantitatively studying DHS is challenging because it is generated through the dehydrogenation of hydrogen-donor solvents produced via the hydrogenation of gas-phase H 2 and solvents. This research establishes for the first time a quantitative method for determining DHS consumption (DHSC) based on protium- and deuterium-nuclear-magnetic-resonance results for solvents after isotope-tracer reactions. Comparative experiments and quantum-chemical calculations were performed to confirm the method’s reliability. The isotope-tracer method showed that DHSC accounts for < 7 % of the total hydrogen consumption under catalysis with ferric stearate, nickel stearate, or molybdenum 2-ethylhexanoate, while DHD consumption accounts for > 50 %. Thus, DHD, rather than DHS, is the primary hydrogen source for catalytic activation. Furthermore, the comparative experiments also showed that hydrogen consumption is greater for one hydrogen source than for the coexistence of the three hydrogen sources, indicating competition among the three sources. The quantum-chemical calculations showed that the competitiveness among the three sources follows the order of DHS < SH < DHD, this agrees with the order of hydrogen consumption in the isotope-tracer experiments. This study quantitatively reveals the mechanism responsible for hydrogen activation by catalysts and provides a scientific basis for optimization and mutual matching of solvents and catalysts.
研究领域:
化学工程
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2025
·
IF 8.2
Mingyue Xie,Yong Wu,Hao Gu,Yuhao Peng,Shan Zhang,Feng Ryan Wang,Wei Xiao,Dong Gu
Deuterated compounds have broad applications across various fields, with dehalogenative deuteration serving as an efficient method to obtain these molecules. However, the diverse electronic structures of active sites in the heterogeneous system and the limited recyclability in the homogeneous system significantly hinder the advancement of dehalogenative deuteration. In this study, we present a catalyst composed of copper single-atom sites anchored within an ordered mesoporous nitrogen-doped carbon matrix, synthesized via a mesopore confinement method. The Cu1/OMNC-1100 catalyst, characterized by Cu–N4 sites, demonstrates exceptional performance, high functional group tolerance, and remarkable durability in the deuteration of 2-bromo-6-methoxynaphthalene under relatively mild conditions (80 °C, 2 MPa of CO). Experimental results combined with X-ray absorption fine structure analysis reveal that Cu–N3 sites can be converted into more stable Cu–N4 counterparts at higher pyrolysis temperatures, resulting in enhanced catalytic activity. This work demonstrates a strategy for designing single-atom site catalysts with tunable coordination environments, providing a promising approach to improving catalytic performance in selective dehalogenative reactions under relatively mild conditions.
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
·
2023
·
IF 3.4
Lewei Zheng,Lingqiao Wang,Dan Li,Chongjun Xie,Zhiyuan Gao,Jinsheng Lin,Jian Ye,Wenbin Chen,Min Li
During the related substances testing of nirmatrelvir , an unknown peak was observed and the level of the peak increased over time during the storage of the sample solution. By using a strategy including LC-PDA/UV-MS n analysis, the degradant was rapidly identified as an epimer of nirmatrelvir, a solution degradation product that is caused by the trace amount of alkaline impurities leaching from the glass HPLC vials. In addition, by using hydrogen/deuterium exchange NMR spectroscopy analysis, the epimerization position was determined to be the carbon α to the adjacent cyano group . Further investigation indicated that the occurrence of the solution degradation can be suppressed when the glass HPLC vials were replaced by plastic HPLC or mass spectrometric grade vials.
研究领域:
药物化学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2020
·
IF 4.939
Xintong Li,Xianglin Wang,Min Li,Junhong Luo,Yongtao An,Peilong Li,Jiangfeng Song,Changan Chen,Xingwen Feng,Shuai Wang
Deuterium has numerous applications in industry and scientific research. However, the conventional methods for separation hydrogen isotopes face the problems of low selectivity and high energy consumption. Recently, microporous material adsorption separation technology provides an efficient way for the separation of hydrogen isotopes. Herein, we prepared the metal bistriazolate framework Ni 2 Cl 2 BBTA, featuring a high density of coordinatively unsaturated Ni 2+ sites. Interactions between the open metal sites and hydrogen render this material excellent separation ability for the capture of D 2 from the hydrogen isotopes mixture, with the D 2 over H 2 selectivity up to 4.5 at 77 K and 4.0 at 87 K respectively. Notably, recycle experiments show that this material has great potential in the application of hydrogen isotope separation, owing to its good structural stability and reusability .
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER
·
2022
·
IF 4.432
Xinxin Tan,Jie Du,Yiliu Liu,Jingwen Ba,Xiaoyu Yang,Xiwen Yang,Meifang Liu,Wenhua Luo
Deuterated polymers have been widely used in many researches, such as small-angle neutron scattering, NMR studies and inertial confinement fusion, but the types of deuterated polymers that can be used are still very limited. In this work, we introduce the concept of supramolecular polymers to develop new deuterated materials toward applications in inertial confinement fusion. To this end, cycloocene- d 14 with deuterium content of 97% is prepared and has been further used as monomers . Deuterated macromonomers with 2-ureido-pyrimidinone as end groups are prepared via either a multistep or a “one-pot” approach. The supramolecular deuterated polymers are formed by the hydrogen-bonding mediated supramolecular polymerization of the macromonomers. With the obtained supramolecular deuterated polymers, uniform polymer shells toward ICF experiments are prepared by the microfluidic technique and solvent evaporation method.
研究领域:
材料科学
·
核物理学
✓ 已验证
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2021
·
IF 6.986
Yunhe Lang,Shihong Wu,Qin Yang,Yanju Luo,Xia Jiang,Peng Wu
D2O plays important roles in a variety of fields (such as the nuclear industry and bioorganic analysis), and thus its isotopic purity (H2O contents) is highly concerned. Due to its highly similar physical properties to H2O and large excess amounts of H2O over D2O, it is challenging to distinguish D2O from H2O. On the basis of the characteristic NIR-II phosphorescence of singlet oxygen (1O2), and the fact that H2O is a more efficient quencher for 1O2 than D2O, here, we proposed to simply use the 1275 nm emission of 1O2 for the analysis of the isotopic purity of D2O. In normal cases (a xenon lamp for excitation), such steady-state emission is extremely weak for valid analytical applications, we thus employed laser excitation for intensification. To this goal, a series of photosensitizers were screened, and eventually polythiophene PT10 was selected with high singlet oxygen quantum yield (ΦΔ = 0.51), high H2O/D2O contrast, and excellent photostability. Upon excitation with a 445 nm laser, a limit of detection (LOD, 3σ) of 0.1% for H2O in D2O was achieved. The accuracy of the proposed method was verified by the analysis of the isotopic purity of several D2O samples (with randomly added H2O). More interestingly, the hygroscopicity of D2O was sensitively monitored with the proposed probe in a real-time manner; the results of which are important for strengthening the care of D2O storage and the importance of humidity control during related investigations. Besides D2O isotopic purity evaluation, this work also indicated the potential usefulness of the NIR-II emission of singlet oxygen in future analytical detection.
研究领域:
分析化学
·
核工业
·
生物有机分析
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FUSION ENGINEERING AND DESIGN
·
2021
·
IF 1.453
Jie Du,Xinxin Tan,Liping Wang,Cheng Qin,Xiaoqiong Chen,Zhigang Wu,Biao Guo,Wenhua Luo
Deuterated-tritiated polymers are a type of promising target materials for inertial confinement fusion (ICF). The preparation of a deuterated-tritiated polymer was performed from a deuterated polybutadiene under tritium through solid state catalytic tritiation with 5 wt% Pd/BaSO 4 as a catalyst. After reaction, the gas mixture in the vessel and the raw T 2 /Ar mixture in the flask were analyzed with a gas chromatography, a quadrupole mass spectrometer and a high resolution gas analysis mass spectrometer. The 2 H-NMR and 3 H-NMR spectra were employed to characterize the deuterated-tritiated polymer. Both isotopic exchange and addition during the reaction were confirmed and the tritium ratio of the deuterated-tritiated polymer was determined to be 26.5 %.The solid state tritiation free of solvents can avoid the generation of high radioactive liquids.
研究领域:
材料科学
·
核物理学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
ANALYST
·
2020
·Vol. 145
·期 13
·4442-4451
·
IF 3.978
Ying Zhang,Xiu Chen,Linzhou Zhang,Quan Shi,Suoqi Zhao,Chunming Xu
Hydrotreatment is extensively used for the production of clean fuel. Attaining an understanding of the structural conversion of the nitrogen species during hydrotreatment is very challenging due to the compositional complexity and the absence of a proper characterization method. In the presented work, we coupled hydrogen/deuterium exchange (HDX) with positive-ion electrospray ionization high-resolution mass spectrometry ((+) ESI HR MS) to investigate the difference between the composition of the nitrogen-containing species and the functional groups before and after hydrotreatment. The solvent and additive were optimized for HDX (+) ESI HRMS through systematic evaluations on model nitrogen-containing compounds. We found that adding deuterated water (D2O) and deuterated formic acid (DCOOD) significantly increased the degree of HDX and thus facilitated the identification of nitrogen functional groups. After application to the hydrotreated petroleum samples, the compositional variation of intermediate amine compounds during the heavy petroleum hydrotreatment process was clearly revealed.
研究领域:
化学
·
能源科学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）