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Dr. Fei-ze Li Jun-shan Geng Dr. Kong-qiu Hu Li-wen Zeng Jing-yang Wang Xiang-he Kong Prof. Ning Liu Prof. Zhi-fang Chai Dr. Lei Mei Prof. Wei-qun Shi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(34):8730-8736
We present here the synthesis of a novel fluorescent actinide polyrotaxane compound URCP1 through the utilization of an end-cutting pseudorotaxane precursor with only the cucurbit[6]uril (CB[6]) macrocyclic components acting as linking struts. The non-coordinating guest motif in the obtained polyrotaxane, with increased freedom and structural flexibility, can display intriguing temperature-triggered conformational variations inside the cavity of CB[6], which was clearly evidenced by crystallographic snapshots at different temperatures. Notably, this observation of temperature-triggered structural dynamics in URCP1 represents the first report of actinide polyrotaxane with such feature in solid-state. Moreover, URCP1 has a high photoluminescence quantum yield (PLQY) of 49.8 %, comparable to other luminescent uranyl compounds, and can work as a fluorescent probe to selectively detect Fe3+ over other eight competing cations in aqueous solution, with the limit of detection being as low as 4.4×10−3 ppm. 相似文献
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Jiazhuang Chen Yuke Zhong Dr. Yalan Liu Dr. Lei Zhang Dr. Mei Li Dr. Wei Han Prof. Zhifang Chai Prof. Weiqun Shi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(42):e202200443
AlCl3-NaCl was utilized as an electrolyte in this work due to its low melting point and Lewis acidity, in which samarium exists in two oxidation states, Sm(III) and Sm(II), resulting in unique electrochemical behaviours. Sm metal dissolves in AlCl3-NaCl melt to form SmCl2, which is verified by electrochemical and spectroscopic techniques. As the Lewis acidity of the melt increases, the diffusion coefficient of Sm(II) gradually increases, and the activation energy of diffusion decreases. Moreover, an additional co-reduction peak of Sm3+ and AlCl4− is observed to be more positive than that of Al(0)/Al(III) in Lewis basic melt, which may be tightly correlated with the variation of Sm(II) coordination in AlCl3-NaCl melt and ligand variation from Cl− to AlCl4− and Al2Cl7− as the Lewis acidity of the AlCl3-NaCl melt increases, according to the in situ electronic absorption spectra of Sm in this melt. 相似文献
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Assessment of the hemolysis and endothelial cell cytotoxicity induced by residual linear alkylbenzene sulfonates on pharmaceutical rubber stoppers based on HPLC‐ESI‐MS
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This study was designed to develop a high‐performance liquid chromatographic–electrospray ionization–mass spectrometry (HPLC‐ESI‐MS) method for quantitative determination of residual surfactant linear alkylbenzene sulfonate (LAS) compounds on pharmaceutical rubber stoppers. An HPLC‐ESI‐MS method was developed for separation and determination of five LAS homologs (C10–C14) under gradient conditions using methanol and ammonium acetate as mobile phases. Hemolysis activity of residual LAS compounds was analyzed by spectrophotometry. Expression of interleukin (IL)‐6 and tumor necrosis factor (TNF)‐α in human umbilical vein endothelial cells (HUVECs) after LAS compound treatment was examined by enzyme‐linked sorbent assay. LAS compounds were well separated and determined by the established gradient conditions. The linear range was 0.05–8 µg/mL with correlation coefficients ≥0.997. Recoveries were from 73 to 134% and the relative standard deviation was <13.7%. There was a correlation between hemolysis rate and LAS compounds concentration when it was ≥0.8 µg/cm2. LAS compounds decreased the viability of HUVECs and promoted the production of IL‐6 and TNF‐α. The developed analytical method was successful for quantitative determination of residual LAS compounds on pharmaceutical rubber stoppers and it is important to monitor and control the amount of LAS compounds on rubber stoppers. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Phenyl‐bridged periodic mesoporous organosilicas (PMOs) functionalized with diphenylphosphino (PPh2‐) ligands were synthesized via a surfactant‐directed self‐assembly approach, and were used as a support to immobilize Ni(II) organometallic complex by coordination interaction. In comparison with Ni‐PPh2‐SBA‐15 and Ni‐PPh2‐PMOs(Et) catalysts, the as‐prepared Ni‐PPh2‐PMOs(Ph) exhibited superior catalytic reactivity and selectivity in water‐medium Sonogashira reaction. A control experiment demonstrated that its high activity could be attributed to the high dispersion of Ni(II) active sites and ordered mesopore channels, which effectively diminished diffusion limitation. Meanwhile, the phenyl organic groups in the support wall enhanced surface hydrophobicity, which promoted the adsorption for organic reactant molecules. Moreover, it displayed almost the same catalytic efficiency with the corresponding homogeneous Ni(PPh3)2Cl2 catalyst and could be used repetitively, which was considered as a more environmentally friendly catalytic process since it simultaneously avoided the use of noble metal active species and toxic organic solvents. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Guoqing Zhang Qingyan Sun Ying Hou Zhanying Hong Jun Zhang Liang Zhao Hai Zhang Yifeng Chai 《Journal of separation science》2009,32(14):2401-2407
The purpose of this paper was to study the enantioseparation mechanism of triadimenol compounds by carboxymethylated (CM)‐β‐CD mediated CE. All the enantiomers were separated under the same experimental conditions to study the chiral recognition mechanism using a 30 mM sodium dihydrogen phosphate buffer at pH 2.2 adjusted by phosphoric acid. The inclusion courses between CM‐β‐CD and enantiomers were investigated by the means of molecular docking technique. It was found that there were at least three points (one hydrophobic bond and two hydrogen bonds) involved in the interaction of each enantiomer with the chiral selectors. A new mathematic model has been built up based on the results of molecular mechanics calculations, which could analyze the relationship between the resolution of enantioseparation and the interaction energy in the docking area. Comparing the results of the separation by CE, the established mathematic model demonstrated good capability to predict chiral separation of triadimenol enantiomers using CM‐β‐CD mediated CE. 相似文献