JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY
·
2022
·
IF 3.262
Qiaohong Lin,Pengyun Li,Ruijun Jian,Yu Xia
Intrachain modifications of membrane glycerophospholipids (GPLs) due to formation of the carbon–carbon double bond (C═C), cyclopropane ring, and methyl branching are crucial for bacterial membrane homeostasis. Conventional collision-induced dissociation (CID) of even-electron ions of GPL favors charge-directed fragmentation channels, and thus little structurally informative fragments can be detected for locating intrachain modifications. In this study, we report a radical-directed dissociation (RDD) approach for characterization of the intrachain modifications within phosphoethanolamines (PEs), a major lipid component in bacterial membrane. In this method, a radical precursor that can produce benzyl or pyridine methyl radical upon low-energy CID at high efficiency is conjugated onto the amine group of PEs. The carbon-centered radical ions subsequently initiate RDD along the fatty acyl chain, producing fragment patterns key to the assignment and localization of intrachain modifications including C═C, cyclopropane rings, and methyl branching. Besides intrachain fragmentation, RDD on the glycerol backbone produces fatty acyl loss as radicals, allowing one to identify the fatty acyl chain composition of PE. Moreover, RDD of lyso-PEs produces radical losses for distinguishing the sn-isomers. The above RDD approach has been incorporated onto a liquid chromatography–mass spectrometry workflow and applied for the analysis of lipid extracts from Escherichia coli and Bacillus subtilis.
研究领域:
分析化学
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生物化学
·
微生物学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2025
·
IF 4
Tao Huang,Chunsu Liang,Jilun Li,Xiaomei Ling
High performance capillary electrophoresis (HPCE) has been widely applied in the analysis of amino acids (AAs), but no studies on the HPCE analysis of dissociated states of AAs have been reported. Here, twenty proteingenic AAs were analyzed by the newly-developed universal interface-induced current detector (IICRD). Two or three current signal peaks were observed in current electrophoretograms (CR-EGs), while only one peak with low sensitivity can be obtained by DAD. The current signal peaks of AAs were accurately identified by adding charge-neutral marker, comparing current signal peaks at different pH conditions, also calculating by p K a . The qualitative analysis indicated that the three current signal peaks of basic AAs were monovalent cations ([AA + ]), charge-neutral forms ([AA ± ]), and monovalent anions ([AA - ]) in order. Similarly, acidic AAs can be detected in three forms as [AA ± ], [AA - ] and [AA 2- ], while neutral AAs can be detected as [AA ± ] and [AA - ]. Quantitative analysis showed that HPCE-IICRD can enhance the sensitivity of AAs to 40 μmol/L in LOD, with a linear range from 10 –6 mol/L to 10 –2 mol/L. Furthermore, interactions between different dissociated states of twenty AAs and l -type amino acid transporter (LAT1) were studied by combined application of NICCE method for the first time. The binding kinetic parameters and mole number of LAT1 on cell membranes can also be obtained. Besides, competitive binding experiments proved that JPH203 (LAT1-specific inhibitor) and leucine shared the same binding site. HPCE-IICRD provides a new method to reveal the interaction between different dissociated forms of AAs or other biomolecules and essential receptors.
研究领域:
生物化学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Cleaner Production
·
2024
·
IF 9.7
Chengling Huang,Youjie Gao,Yi Chen,Yunfei Shen,Hou-Yong Yu
Earth has become depleted of oil and has suffered from the misuse of non-biodegradable plastics. Significant efforts have been dedicated to addressing the application flaws of cellulose as a substitute for plastics derived from petroleum. One of key defects was non-hydrophobic nature which highly influenced the mechanical properties of cellulose material during practical uses. Here, an innovative method was proposed to achieve hydrophobic modification of cellulose films through the molecular dissociation of dodecyltrimethoxysilane (DTMS) without the use of any toxic agents during the cellulose regeneration process. The hydrophobic (water contact angle of 118°), transparent (transmittance of 85%), and high-strength (70 MPa) DC films (cellulose films modified by DTMS) were successfully fabricated via cellulose regeneration process tailored by DTMS after molecular dissociation. The DC films stood out in both hydrophobicity and strength compared with several commercial plastics and the possible hydrophobic mechanism was proposed. Furthermore, the obsession with smart sensing abilities in DC films has made it a potential tool for monitoring baby diapers. Therefore, unlike conventional concepts, the methodology we adopted is simple and efficient, and it also eliminates the need for cellulose and replaces it with plastics.
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
ACS ES&T Engineering
·
2023
·
IF 7.1
Peng Chen,Yun Wang,Jiazhen Liao,Yi Liang,Qingqing Ye,Yi Wang,Zhongwei Jiang,Chunhui Shan,Wendong Zhang,Fan Dong
The dissociation of H2O molecules plays an important role in producing protons for promoting hydrogenation reduction of CO2. Therefore, developing excellent photocatalysts to promote the dissociation of H2O molecules and reveal the effect mechanism is the key research direction to enhance CO2 reduction efficiency. In this work, we synthesized BiSbO4 with oxygen vacancies (OVs) to investigate the photocatalytic mechanism of CO2 conversion and H2O dissociation. Experimental results indicate that the introduction of OVs into BiSbO4 can enhance the absorption capacity of light, narrowing band gaps and impeding the recombination of photogenerated carriers. Importantly, the existence of OVs in BiSbO4 can promote the adsorption and activation of H2O molecules via the stronger covalent interaction, which facilitates the dissociation of H2O molecules to generate more protons and lowers the energy barriers of •COOH to improve the efficiency of CO2 reduction. This study reinforces our understanding of the principle of photocatalytic CO2 reduction and the important role of H2O dissociation in photocatalytic CO2 conversion.
研究领域:
材料科学
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环境科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE
·
2025
·
IF 3.6
Yi Wang,Jiayi Chen,Bin Wang,Hao Wang
Microneedles (MNs) are widely utilized in percutaneous drug delivery systems and represent a crucial approach for drug or vaccine administration. The conductive MNs further enhance the controllability and functionality of these devices, thereby expanding their potential biomedical applications. Given its high biocompatibility and degradability, gelatin emerges as an ideal material for fabricating MNs. However, owing to its inherent hydrogen bonding, gelatin solutions exhibit high viscosity and tend to solidify at room temperature, thus limiting their processability in the preparation of gelatin MNs. In this study, a novel approach was proposed to enhance the fluidity of the gelatin solution and reduce its solidification temperature by adding citric acid as a hydrogen bonding dissociator, thereby facilitating its use in MN fabrication. Furthermore, citric acid functioned not only as a hydrogen bonding dissociator but also as a dopant in the 3,4-ethylenedioxythiophene (EDOT) polymerization process, demonstrating dual functionality and effectively yielding gelatin/poly 3,4-ethylenedioxythiophene (PEDOT) MNs. This research presents an innovative strategy for developing gelatin-based MNs and advances their potential applications in intelligent medical fields. Graphical Fabrication and characterization of conductive Microneedles.
研究领域:
生物材料学
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药物递送系统
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生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2025
·
IF 9
Xiaoqing Wang,Jinyun Xu,Shijie Shang,Ming Li,Sijia He,Xiaoyan Wang,Bingyu Yang,Yirang He,Xiaolu Ru,Yanyan Ji,Wenju Zhu,Chunming Zheng,Xiaohong Sun
Bipolar membranes (BPMs), composed of anion exchange membrane (AEM) and cation exchange membrane (CEM), hold promise for energy and environmental applications due to their ability to dissociate water into H + and OH − under reverse bias. However, their practical voltage requirements often exceed theoretical potentials, necessitating efficiency optimization. This study introduces an innovative BPM design integrating alginate (SA)-based CEM with chitosan AEM, enhanced by polydopamine-coated halloysite nanotubes (DHNTs) loaded with phosphotungstic acid (HPW). The tubular structure of the DHNTs, modified via dopamine polymerization, improved mechanical stability and proton conductivity, while HPW coating (optimized at 10 wt %) facilitated acid-base interactions, reducing proton hopping distances. Comprehensive characterization (SEM, FTIR, XPS, TGA) confirmed successful HPW coating and structural modification. The optimized BPM exhibited enhanced tensile strength than unmodified BPM with proton conductivity of 36.56 mS/cm and low water dissociation overpotential of 1.188 V at 70 mA/cm 2 . Electrodialysis tests revealed reduced interfacial resistance (IR drop) and increased stability over 48 h, attributed to HPW's catalytic role in accelerating ion transport and minimizing energy loss. The synergy between DHNTs and HPW significantly improved hydrophilicity, mechanical robustness, and energy efficiency, demonstrating the potential of this design for sustainable electrochemical systems. These findings provide critical insights into advanced BPM development for scalable energy and environmental technologies.
研究领域:
材料科学
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能源技术
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF MASS SPECTROMETRY
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2010
·
IF 2.117
Mingfeng Xie,Zhongyue Zhou,Zhandong Wang,Dongna Chen,Fei Qi
The near-threshold absolute photoionization cross-sections of 12 oxygenated hydrocarbons, including 1-butanol, 2-butanol, iso -butanol, tert -butanol, 1-pentanol, tert -pentanol, iso -pentanol, methyl tert -butyl ether (MTBE), ethyl tert -butyl ether (ETBE), furan, 2-methylfuran, 2,5-dimethylfuran, were measured in the photon energy range from respective ionization thresholds to 11.5 eV. The experiments were performed with photoionization mass spectrometry and tunable synchrotron vacuum ultraviolet (VUV) light. Binary-liquid-mixtures of the investigated sample and benzene were used in the measurements where benzene acts as a calibration standard, due to its well known photoionization cross-section at the photon energies from its ionization energy (9.24 eV) to 11.5 eV. Photodissociative fragments from the molecules were also observed, and their photodissociation cross-sections are also presented.
研究领域:
化学
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
FLUID PHASE EQUILIBRIA
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2015
·
IF 2.2
Xingchu Gong,Shichao Huang,Ruonan Jiao,Jianyang Pan,Yao Li,Haibin Qu
A liquid–liquid equilibrium method to determine dissociation constants was presented in this work using phenolic acids in the water extract of Salvia miltiorrhiza as a sample. The models to quantitatively describe the relationship between aqueous phase pH value and apparent distribution coefficient value were built. Apparent distribution coefficients are determined after liquid–liquid equilibrium experiments. The pK a values of phenolic acids in S. miltiorrhiza extracts were fitted successfully. The dissociation constants of active ingredients that are in a mixture in which most components are unknown can be determined using this method. The distribution coefficients of active ingredient molecules and ions can also be obtained. 1-Octanol is a recommended solvent with low solubility, high boiling point, and extra information of K ow .
研究领域:
药理学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING RESEARCH & DESIGN
·
2022
·
IF 4.119
Haitao Zhou,Kun Huang
A new approach using water as the stripping phase for extraction and recovery of low-concentration Ga (III) from concentrated hydrochloric acid solutions by Aliquat 336-based supported liquid membrane (SLM) is suggested. Generally, the stripping of Ga (III) from the loaded organic phase during liquid-liquid two-phase stirring extraction using quaternary ammonium salt as an extractant is extremely difficult. However, in the present work, an efficient mass transfer of low-concentration Ga (III) through the SLM was observed by introducing a low acidity (pH=2) aqueous solution as the stripping phase of the SLM. It was revealed that dissociation of GaCl 4 - and HCl 2 - anions into Ga 3+ , Cl - and H + ions at the stripping/membrane phase interface play an important role in driving the mass transfer of GaCl 4 - from the concentrated hydrochloric acid solutions towards stripping phases. Kinetic analysis suggests that the permeability coefficient of Ga (III) ions through the SLM is dependent on the reaction temperature, extractant Aliquat 336 concentrations, and the difference in Cl - concentrations between the two sides of the liquid membrane phase , but independent of H + concentrations. In view of future’s applications for selective separation and recovery of low-concentration Ga (III) from the concentrated hydrochloric acid leaching solutions of various gallium-containing solid wastes, separation selectivity of Ga (III) against other coexisting metal impurity ions, such as Fe (II), Al (III), Mg (II) and Cu (II), was also evaluated.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Energy & Environmental Materials
·
2021
·Vol. 6
·期 1
·e12292
·
IF 15.122
Ruofan Shen,Yanyan Liu,Hao Wen,Xianli Wu,Zhikun Peng,Sehrish Mehdi,Tao Liu,Huanhuan Zhang,Shuyan Guan,Erjun Liang,Baojun Li
The dissociation of water is the rate-determining step of several energy-relating reactions due to high energy barrier in homolysis of H-O bond. Herein, engineering vacancy-atom ensembles via injecting oxygen vacancy (V O ) into single facet-exposed TiO 2 -Pd catalyst to form V O -Pd ensemble is proposed and implemented. The outstanding activity of as-prepared catalyst, 1.5-PdTV O , toward water dissociation is established with a turnover frequency of 240 min −1 in ammonia borane hydrolysis at 298 K. Density functional theory simulation suggests that the V O -Pd ensemble is responsible for the high intrinsic catalytic activity. Water molecules tend to be dissociated on V O sites and ammonia borane molecules on Pd atoms. Those H atoms from water dissociation on V O combine with H atoms from ammonia borane on Pd atoms to generate H 2 . This insights into engineering vacancy-atom ensembles catalysis provide a new avenue to design catalytic materials for important energy chemical reactions.
研究领域:
材料科学
·
催化化学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Omega
·
2020
·
IF 2.87
Bo Gao,Gengxin Wang,Bao Li,Lixin Wu
To understand the self-inclusion and the dissociation in a branched β-cyclodextrin (CD) system, we designed and synthesized a β-CD trimer in which each CD group is connected to one of bridging arms of a planar triphenylbenzene core through a CuAAC click reaction. Only one rather than two or all of the three host CDs was demonstrated to be in a self-including state in water, while no self-inclusion was observed to occur in dimethylsulfoxide (DMSO) via the characterization of 1H and NOESY NMR spectra. The configuration structures of the CD groups in the self-included state were evaluated, and the dissociation to free state in water was investigated under various conditions like heating, increased acidity, and discharging versus the addition of competitive guests. While raised temperature and increased acidity did not break the self-inclusion, two adamantane guest molecules were found to show capability in driving the equilibrium to get back to free state against the self-inclusion. The inclusion process of the added guests was believed to involve in the dissociation of the self-inclusion and the occupation of the guests in CD cavity. The results of host–guest interaction study indicated that the stable combination of guests was favorable for blocking the structural overturning of glucose toward trapping the bridging group into the cavity.
研究领域:
化学
·
分子生物学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF MASS SPECTROMETRY
·
2014
·
IF 2.227
Y.Y. Wang,X. Kang,Y.W. Liu,W.Q. Xu,L. Wang,C.Z. Hu,J. Chen,F.Y. Liu,L.S. Sheng,X.L. Zhao,P.F. Zhang,L.F. Zhu
Using vacuum ultraviolet photons produced by synchrotron radiation and reflection time-of-flight mass spectrometer, dissociative photoionization of isooctane was measured in the photon energy region of 9.7–15.6 eV under ultrasonic molecular beam. Then the dissociative ionization products at different photon energies were obtained. By measuring the photoionization efficiency curves, the appearance potentials of the dominative ion fragments and the vertical ionization energy of isooctane were determined. In addition, combining with G3 calculations we obtained the structure and energy of the parent, neutral and ion fragments. By comparing the experimental measurements with the theoretical calculations, the dissociative photoionization channels of isooctane were elucidated, and formation enthalpies of the fragmented ions and the dissociation energy of the parent ion were obtained.
研究领域:
化学物理
·
分子光谱学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）