RAPID COMMUNICATIONS IN MASS SPECTROMETRY
·
2020
·Vol. 34
·期 21
·e8899
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IF 2.2
Hanfeng Jin,Jiuzhong Yang,Aamir Farooq
Rationale Aromatic hydrocarbons play an important role in the formation and growth of polycyclic aromatic hydrocarbon (PAH) and soot particles. Measurements of their absolute photoionization cross-sections (PICSs), that benefit the quantitative investigation of mass spectrometry, are still lacking, however. Methods PICSs of some aromatic hydrocarbons were measured with tunable synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS). Nitric oxide and benzene were chosen as standard references for PICS calibration, since their photoionization cross-sections are well documented in the literature. Binary liquid mixtures of the investigated molecules and their specific solvents were used in the measurements. Results The investigated aromatics include naphthalene, phenanthrene, 1-methylnaphthalene, indene, 2-/3-/4-methylphenylacetylene, 2-methylindene, diphenylacetylene, 1-/2-ethynylnaphthalene and acenaphthylene. Photo-induced fragments from the molecules were also observed with increasing photon energy. Conclusions Based on our measurements and literature data, PICSs of most aromatic molecules have very similar values beyond their ionization energies. However, molecules that contain the phenylacetylene structure have PICSs higher than other aromatics.
研究领域:
分析化学
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质谱学
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大气化学
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环境科学
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产品关联
DOI
PubMed
高影响因子
PEST MANAGEMENT SCIENCE
·
2023
·
IF 4.1
Yifan Li,Shujun Ni,Yunping Wang,Ruichi Li,Hong Sun,Xuan Ye,Zhen Tian,Yalin Zhang,Jiyuan Liu
BACKGROUND Insecticide resistance continuously poses a threat to agricultural production. Chemosensory protein-mediated resistance is a new mechanism of insecticide resistance discovered in recent years. In-depth research on resistance mediated by chemosensory proteins (CSPs) provides new insight into aid insecticide resistance management. RESULTS Chemosensory protein 1 in Plutella xylostella ( PxCSP1 ) was overexpressed in the two indoxacarb-resistant field populations and PxCSP1 has a high affinity with indoxacarb. PxCSP1 was upregulated when exposed to indoxacarb and the knockdown of this gene elevated sensitivity to indoxacarb, which demonstrate that PxCSP1 is involved in the indoxacarb resistance. Considering that CSPs may confer resistance in insects via binding or sequestering, we explored the binding mechanism of indoxacarb in PxCSP1 -mediated resistance. Using molecular dynamics simulations and site-directed mutation, we found that indoxacarb forms a solid complex with PxCSP1 mainly through van der Waals interactions and electrostatic interactions. Between these, the electrostatic interaction provided by the Lys100 side chain in PxCSP1 , and especially the hydrogen bonding between the NZ atom and the O of the carbamoyl carbonyl group of indoxacarb, are the key factors for the high affinity of PxCSP1 to indoxacarb. CONCLUSIONS The overexpression of PxCPS1 and its high affinity to indoxacarb is partially responsible for indoxacarb resistance in P. xylostella . Modification of indoxacarb's carbamoyl group has the potential to alleviate indoxacarb resistance in P. xylostella . These findings will contribute to solving chemosensory protein-mediated indoxacarb resistance and provide a better understanding of the insecticide resistance mechanism. © 2023 Society of Chemical Industry.
研究领域:
昆虫学
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分子生物学
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农药科学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
·
2020
·
IF 3.209
Youxi Jin,Yu Pan,Biao Jin,Dongri Jin,Chunbo Zhang
(S)-1-(5-(4-Methylpiperazin-1-yl)-2,4-dinitrophenyl)pyrrolidine-2-carboxylic acid (Pro-PPZ) was employed as a chiral derivatization reagent (CDR) for the efficient enantioseparation and ultrasensitive mass spectrometric detection of chiral amines. Pro-PPZ was prepared from the one-step reaction of 1-(5-fluoro-2,4-dinitrophenyl)-4-methylpiperazine (PPZ) and l -proline. Two amines and two amino acid methyl esters were selected as model chiral amines, which were easily labeled with Pro-PPZ under mild reaction conditions (35 °C for 10 min) generating Pro-PPZ-amine derivatives. The resulting diastereomers were completely separated by reversed-phase liquid chromatography (RP-LC) using an ODS column ( R s = 3.4–17.0 for amines). Ultrasensitive detection limits on femtomolar level were obtained for the tested amines using multiple reaction monitoring (MRM) chromatograms at a single monitoring ion, m/z 289 (0.1–5.0 fmol for amines). The practical metabolite analysis of (R)-1-aminoindan (R-AI) in saliva samples was performed by LC–MS/MS using the Pro-PPZ derivatization method. The method was validated in terms of precision, accuracy, and linearity. Using this method, R-AI concentrations in saliva were determined after a single oral administration of the drug rasagiline to healthy male and female subjects, but no (S)-1-aminoindan (S-AI) was detected, which suggesting that R-AI was not converted into S-enantiomer in the metabolic process. R-AI concentrations in four healthy volunteers ranged from 32.85 nM to 49.45 nM, with an average value of 43.76 nM. To date, there is no LC–MS (or MS/MS) method reported for the enantioselective determination of R-AI in human saliva samples.
研究领域:
分析化学
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药物代谢
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临床医学
✓ 已验证
DOI
高影响因子
TETRAHEDRON
·
2017
·
IF 2.651
Bing Lin,Wen-Hui Zhang,Dan-Dan Wang,Yi Gong,Qi-Di Wei,Xiong-Li Liu,Ting-Ting Feng,Ying Zhou,Wei-Cheng Yuan
Developed herein is a diversity-oriented one-pot multicomponent synthesis of polycyclic 3,3′- pyrrolidinyl-dispirooxindoles 3 via a multicomponent 1,3-dipolar cycloaddition event of 3-methyl-4-nitro-5-isatylidenyl-isoxazoles 2 with azomethine ylides (thermally generated in situ from isatins and proline or thioproline). Products bearing four consecutive stereocenters consist of two oxindole moieties and a polycyclic pyrrolidinyl core, including vicinal spiroquaternary stereocenters fused in one ring structure were smoothly obtained in high yields (up to 85% yield) with good diastereoselectivity (up to >20:1). Valuable features of this method were application of 3-methyl-4-nitro-5-isatylidenyl-isoxazoles as 1,3-dipolarophiles and the design of new hybrid architectures for biological screenings through the adequate fusion of these sub-units of isoxazole and 3,3′-pyrrolidinyl-dispirooxindole, generating drug-like molecules.
研究领域:
有机化学
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药物化学
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肿瘤学
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产品关联
DOI
高影响因子
TETRAHEDRON
·
2017
·
IF 2.651
Ling-Ling Wu,Gao H. Yang,Zhi Guan,Yan-Hong He
The Rose Bengal sensitized intermolecular [2 + 2]-cycloaddition of 3-ylideneoxindoles for the synthesis of spirocyclic oxindoles was developed successfully under visible light irradiation conditions. The cycloaddition products were obtained in good yields (up to 93%) with excellent diastereoselectivity and regioselectivity by using a low loading of Rose Bengal (0.125 mol%) as a triplet sensitizer. This work demonstrates the potential benefits of Rose Bengal in visible light catalysis.
研究领域:
有机化学
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光化学
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产品关联
DOI
高影响因子
ANALYST
·
2022
·Vol. 147
·期 18
·4132-4140
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IF 5.227
Lingfeng Xu,Fangzhi Xiong,Minqing Kang,Yanrong Huang,Kui Wu
Viscosity is one of the most important physical parameters in a liquid, noninvasive, and effective viscosity inspection method toward liquid safety that needs to be developed urgently. In this study, two kinds of novel molecular sensors, namely, DPBID and DPTMID, were strategically constructed by the triphenylamine indanedione derivates; the rotatable conjugate structure was utilized as the recognition site and fluorescence quencher. This couple of molecular sensors was synthesized in a one-step facile manner. DPTMID displayed longer emission wavelength and larger Stokes shift (195 nm in water, 138 nm in glycerol) with a narrower energy band. Moreover, DPTMID exhibited high selectivity, sensitivity, and significant fluorescence signal enhancement toward a higher viscous microenvironment. The molecular sensor displayed good photostability, selectivity, and universality in various commercial liquids and featured with typical aggregation-induced emission (AIE). With the aid of DPTMID, the thickening effects of liquid thickeners can be captured. More importantly, DPTMID was explored to visualize the viscosity fluctuations during the metamorphic stages of liquids, and it was found that the microenvironment viscosity level is closely related to the spoilage degree of liquids. The method with rapid detection, high sensitivity, cheap equipment, and fast results output toward food quality and safety inspection can be achieved through this study.
研究领域:
化学
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材料科学
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食品安全
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产品关联
DOI
PubMed
高影响因子
PROCEEDINGS OF THE COMBUSTION INSTITUTE
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2025
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IF 5.2
Zhaohan Chu,Zhongkai Liu,Changyang Wang,Long Zhao,Bin Yang
An experimental study was conducted to investigate the weight growth routes from o -methylphenyl radical ( o -CH 3 C 6 H 4 ) to indene. o -Nitrosotoluene served as the precursor for o -methylphenyl radicals in this study. Co-pyrolysis of o -methylphenyl radical/C 2 H 2 and o -methylphenyl radical/C 2 H 4 was investigated utilizing the chemical microreactor and synchrotron vacuum ultraviolet photoionization mass spectrometry. Sampled mass-specific photoionization efficiency (PIE) curves were employed to identify the aromatic species, elucidating interactions between o -methylphenyl radicals and C 2 species. The species detected at m/z = 116 and 118, essential for understanding the reaction mechanism, were identified via matching photoionization cross-sections and adiabatic ionization energies with literature and theoretical values. Specifically, indene and its isomer o -methylphenylacetylene ( m/z = 116) were determined in the reaction of o -methylphenyl radical with C 2 H 2 , while indene and o -methylstyrene ( m/z = 118) were identified in the reaction of o -methylphenyl radical with C 2 H 4 . By combining the identified intermediate species with previous literature basis, the formation pathways for indene, originating from o -methylphenyl radical were discussed in both reaction systems, providing further insights for understanding the indene formation pathways.
研究领域:
物理化学
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燃烧化学
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分子反应动力学
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质谱分析
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有机反应机理
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产品关联
DOI
高影响因子
JOURNAL OF FLUORESCENCE
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2024
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IF 2.6
Wang Wenxiang,Gan Yudie,Jiang Huaqin,Fang Min,Wu Zhenyu,Zhu Weiju,Li Cun
Hydrogen sulfide (H 2 S) plays a key role in the physiology and pathology of organisms, and H 2 S in the environment is easily absorbed and harmful to health. It is of great significance to develop a probe with good selectivity, high sensitivity and good stability that can detect hydrogen sulfide inside and outside organisms. In this work, we designed a novel “turn-on” fluorescent probe CIM-SDB for the detection of H 2 S. The probe CIM-SDB used indene-carbazole as the fluorophore and 2,4-dinitrobenzenesulfonyl as the recognition site. The probe CIM-SDB exhibited high selectivity and sensitivity to H 2 S (detection limit as low as 123 nM). Moreover, the probe CIM-SDB was successfully applied to the detection of intracellular exogenous and endogenous H 2 S, and the test strips prepared by the probe CIM-SDB could realize the convenient and rapid detection of H 2 S.
研究领域:
分析化学
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生物化学
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环境科学
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DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 51
·45864-45872
·
IF 3.289
Yafei Wang,Jiang Fan,Tianyi Li,Qiong Wang,Junwei Shi,Zuoming Qu,Hua Tan,Yu Liu,Weiguo Zhu
Two binuclear platinum metallomesogens possessing a 6,12-dihydro-indeno[1,2-b]fluorene bridge, FJ-1 and FJ-2, have been synthesised and characterised by 1H and 13C NMR, TOF-MS and elemental analysis. Their thermal properties were studied by polarised optical microscopy and differential scanning calorimetry. Upon photoexcitation in solution, both complexes exhibited dual fluorescence (1π–π*)/phosphorescence (3π–π*) emission covering most of the visible spectrum (from about 460 nm to 750 nm). This uncommon behaviour has been further investigated by time-resolved optical spectroscopy, including nanosecond time-resolved transient absorption spectroscopy, and further insights were obtained by means of density functional theory (DFT) and time-dependent DFT (TD-DFT). An organic light-emitting diode (OLED) using FJ-1 was prepared. Importantly the two emission bands are retained in electroluminescence. This result suggests that controlling spin–orbit coupling to obtain dual emission can provide an effective way of achieving broadband emission based on a single molecule.
研究领域:
化学
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材料科学
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光物理学
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DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
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2020
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IF 4.049
Qian Yuan,Meiling Qi
This work presents a new triptycene-based dicationic guanidinium ionic liquid (TPG) as the stationary phase for gas chromatography (GC). To our knowledge, this is the first example of employing a dicationic guanidinium ionic liquid (GIL) for chromatographic analyses. As a result, the TPG column exhibited moderate polarity and column efficiency of 3840 plates/m and 3120 plates/m measured by naphthalene and 1-octanol at 120 °C, respectively. Particularly, the TPG column exhibited distinctly advantageous performance for the challenging Grob test mixture and the isomer mixture of phenols and anilines over the monocationic GIL and its counterpart with dicationic immidazolium units (TP-2IL). Also, it showed higher selectivity towards the isomers of alkanes, alcohols, diethylbenzenes, bromotoluenes, bromonitrobenzenes than the commercial DB-35MS column. Moreover, the TPG column achieved improved thermal stability over the GIL column and excellent repeatability with the RSD values of 0.01–0.05% for run-to-run, 0.11–0.24% for day-to-day and 2.4–4.1% for column-to-column. Its application to GC–MS analysis of the essential oil of Mentha haplocalyx proved its good potential for analysis of complex samples.
研究领域:
分析化学
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材料科学
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产品关联
DOI
PubMed
高影响因子
CHEMISTRY & BIODIVERSITY
·
2024
·
IF 2.3
Xue-Song Tang,Lin-Yu He,Sheng-Nan Li,Wen-Cheng Zhang,Ze-Yu Wu,Ai-Ling Hui
Vascular dementia (VaD) is a neurodegenerative disease resulting from cerebral vascular obstruction, leading to cognitive impairment, and currently lacks effective treatment options. Due to its complex pathogenesis, multi-target drug design (MTDLs) strategies are considered among the most promising therapeutic approaches. In this study, we designed and synthesized a series of novel indanone derivatives targeting targets related to vascular health and dementia. The results indicated that compound C 5 exhibited excellent acetylcholinesterase inhibitory activity (IC 50 =1.16 0.41 μM) and anti-platelet aggregation activity (IC 50 =4.92±0.10 μM) within ranges of 0.1–1000 μM and 0.03–300 μM, respectively, possibly mediated by molecular docking interactions. Furthermore, compound C 5 demonstrated protective effects on cells at concentrations ≤50 μM, significantly reducing the release of nitric oxide (NO), tumor necrosis factor-alpha (TNF-α), and interleukin-1 beta (IL-1β) in a concentration-dependent manner, showcasing its potent neuroinflammatory inhibitory effects. Anti-inflammatory therapies are regarded as effective strategies for treating VaD. Therefore, compound C 5 holds promise as a novel candidate drug for further investigation into the treatment of vascular dementia. Graphical
研究领域:
神经病学
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药理学
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药物设计
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DOI
PubMed
高影响因子
INORGANIC CHEMISTRY COMMUNICATIONS
·
2023
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IF 3.8
Xiang Hu,Yanchen Huo,Xuyang Yan,Fei Wang,Li Pan,Xiaochao Shi
As Cp-derived ligands, substituted 4,5,6,7-tetrahydroindene (THI) ligands with tunable steric bulk have been synthesized, and their ligated half-sandwich rare-earth metal complexes were also sucessfully prepared and tested for styrene (co)polymerization. In conjunction with [Ph 3 C][B(C 6 F 5 ) 4 ], the THI-ligated scandium complexes exhibited high catalytic activity for highly syndiotactic polymerization of styrene (>99% rrrr ). THI 3Me -Sc /[Ph 3 C][B(C 6 F 5 ) 4 ] binary system also promoted the copolymerization of styrene and isoprene/butadiene by both the concurrent addition and sequentical addition of monomers, affording the copolymers with block microstructure as deterimined by NMR ( 1 H and 13 C) spectra. The huge difference in reactivity ratios betewen styrene and isoprene/butadiene ( r IP / r St = 31.1 and r BD / r St = 173.6) revealed in kinetics investigation further proved the predominantly block structure of resultant copolymers.
研究领域:
高分子化学
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催化化学
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材料科学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）