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91.
Multiplex bead-array competitive immunoassay for simultaneous detection of three pesticides in vegetables 总被引:1,自引:0,他引:1
We report on a multiplex bead-based competitive immunoassay using suspension array technology for the simultaneous detection of the pesticides triazophos, carbofuran and chlorpyrifos. Three hapten-protein conjugates were covalently bound to carboxylated fluorescent microspheres to serve as probes. The amount of conjugates and antibodies were optimized. The new multi-analyte assay has dynamic ranges of 0.02–50 ng?mL?1, 0.5–500 ng?mL?1 and 1.0–1000 ng?mL?1 for triazophos, carbofuran and chlorpyrifos, respectively, and the detection limits are 0.024, 0.93 and 1.68 ng?mL?1. This new multiplex assay is superior to the traditional ELISA in possessing a wider detection range, better reproducibility and the feature of multi-target detection. Cross-reactivity studies indicated that the bead-array method is highly selective for the three target pesticides, and that individual analyses have no significant influence between each other, also without cross-reactions from other structurally related pesticides. The method was applied to analyze vegetables spiked with the three pesticides, and the recoveries were in ranges of 78.5–112.1 %, 72.2–120.2 % and 70.2–112.8 %, respectively, with mean coefficients of variation of <15 %. Figure
Schematic illustration of the multiplex bead-based competitive immunoassay 相似文献
92.
Abstract Task‐specific ionic liquids possessing two Brönsted acid sites with –COOH, HSO? 4, or H2PO? 4 groups have been designed, synthesized, and characterized. Under mild conditions and without any additional organic solvent, the esterification of isopropanol by chloroacetic acid could be carried out in these new task‐specific ionic liquids. In comparison with most of acidic ionic liquids in current use, these ionic liquids are halogen free and more environmentally benign as media and catalysts. 相似文献
93.
Abstract A series of novel Mahkoside A derivatives was synthesized, and their in vitro cytotoxic activities were evaluated against the human cancer cell line Ec‐9706. A Preliminary structure–activity relationship study showed compounds 7 and 8 have obvious cytotoxic activities (IC50: 30.0 and 12.5 µg · mL?1, respectively). 相似文献
94.
Chang Jun Zou Quan Wu Tang Gui Hong Lan Qiang Tian Tai Yu Wang 《Journal of inclusion phenomena and macrocyclic chemistry》2013,76(1-2):61-68
For the first time, hydroxypropyl-β-cyclodextrin (HP-β-CD) has been brought in to include 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTCA) in order to enhance inhibition efficiency of PBTCA, which leads a new approach to study oil–gas field corrosion inhibition in the process of acid treatment. Based on the host–guest inclusion reaction, the inclusion complex of PBTCA with HP-β-CD has been prepared in the laboratory. UV–Vis absorption spectrum was applied to study the inclusion behavior of PBTCA with HP-β-CD. The results revealed that PBTCA with HP-β-CD can form a 1:1 stoichiometry inclusion complex. The 1:1 inclusion complex synthesized by using lyophilization was further characterized by Fourier transform infrared spectroscopy. Besides, inhibition effect of the inclusion complex on the corrosion inhibition of Q235 carbon steel has been investigated in 0.1 M sulfuric acid (H2SO4) solution using potentiodynamic polarization, electrochemical impedance spectroscopy techniques and scanning electron microscopy (SEM). It was found that the presence of the inclusion complex better achieved the anti-corrosion property in aggressive medium than was the case with alone PBTCA and the highest inhibition efficiency of the inclusion complex over 90 % was obtained, which are suggestive of the active effect of the inclusion complex for improving inhibition efficiency of PBTCA. Meanwhile, the results obtained from SEM further showed that the inclusion complex acts as a more efficient corrosion inhibitor for Q235 carbon steel in H2SO4 medium. 相似文献
95.
Wenbo Wu Dr. Guohua Xu Prof. Conggang Li Prof. Gui Yu Prof. Yunqi Liu Prof. Cheng Ye Prof. Jingui Qin Prof. Zhen Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(21):6874-6888
Through the combination of the divergent and convergent approaches, coupled with the utilization of the powerful Sharpless “click‐chemistry” reaction, two series of sulfonyl‐based high‐generation NLO dendrimers were conveniently prepared with high purity and in satisfactory yields. Thanks to the perfect three‐dimensional (3D) spatial isolation from the highly branched structure and the isolation effect of the exterior benzene moieties and the interior triazole rings, these dendrimers exhibited large second harmonic generation coefficient (d33) values up to 181 pm V?1, which, to the best of our knowledge, is the highest value so far for polymers containing sulfonyl‐based chromophore moieties. Meanwhile, compared with the nitro‐chromophore‐based analogues, their optical transparency and NLO stability were improved in a large degree, due to the lower dipole moment (μ) and the special main‐chain structure of sulfonyl‐based chromophore in these dendrimers. 相似文献
96.
利用Mawhin延拓定理考察了一类分数阶微分方程m点边值共振问题解的存在性.得到了解的存在性的一个充分性条件,并且举出实例用以说明主要结果. 相似文献
97.
Guang Gui Ding 《数学学报(英文版)》2015,31(12):1872-1878
In this article, we use some analytic and geometric characters of the smooth points in a sphere to study the isometric extension problem in the separable or reflexive real Banach spaces. We obtain that under some condition the answer to this problem is affirmative. 相似文献
98.
It is a well-known fact that characters of a finite group can give important information about the group's structure. Also it was proved by the third author of this article that a finite simple group can be uniquely determined by its character table. Here the authors attempt to investigate how to characterize a finite almost simple group by using less information of its character table, and successfully characterize the almost simple K3-groups by their orders and at most three irreducible character degrees of their character tables. 相似文献
99.
Yutaka Aoyagi Kei Ozawa Tatsuya Kobayashi Tomoyo Hasuda Ming-Yu Gui Yong-Ri Jin Xu-Wen Li Haruhiko Fukaya Reiko Yano Yukio Hitotsuyanagi Koichi Takeya 《Tetrahedron》2014
Transformation of plant-origin 7,14-dihydroxy-ent-kaurenes to ent-abietanes having a cis-fused α-methylene γ-lactones was accomplished efficiently under the Mitsunobu reaction conditions. The yields of the desired products were apparently influenced by the steric hindrance at C-1. The cytotoxic activity on P388 murine leukemia cells of the ent-abietanes having cis-fused α-methylene γ-lactones produced were assayed. 相似文献
100.
Gui‐Xia Wang Li‐Li Shang Zhao‐Hao Li Bang‐Tun Zhao 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(7):715-717
A novel manganese coordination polymer, poly[(μ5‐thiophene‐3,4‐dicarboxylato)manganese(II)], [Mn(C6H2O4S)]n, was synthesized hydrothermally using 3,4‐thiophenedicarboxylate (3,4‐tdc2−) as the organic linker. The asymmetric unit of the complex contains an Mn2+ cation and one half of a deprotonated 3,4‐tdc2− anion, both residing on a twofold axis. Each Mn2+ centre is six‐coordinated by O atoms of bridging/chelating carboxylate groups from five 3,4‐tdc2− anions, forming a slightly distorted octahedron. The Mn2+ centres are bridged by 3,4‐tdc2− anions to give an infinite two‐dimensional layer which incorporates one‐dimensional Mn–O gridlike chains, and in which the 3,4‐tdc2− anion adopts a novel hexadentate chelating and μ5‐bridging coordination mode. The fully deprotonated 3,4‐tdc2− anion exhibits unexpected efficiency as a ligand towards the Mn2+ centres, which it coordinates through all of its carboxylate O atoms to provide the novel coordination mode. The IR spectrum of the complex is also reported. 相似文献