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31.
HPLC-MS-MS法测定水体中残留的氨基甲酸酯类农药 总被引:2,自引:0,他引:2
应用高效液相色谱-串联质谱(HPLC-MS-MS)联用技术,建立了检测水体中氨基甲酸酯类农药残留的方法。水样经氨基柱固相萃取,二氯甲烷洗脱,梯度流动相洗脱,电喷雾正离子(ESI+)模式采集、选择反应性监测模式(SRM)对定性、定量离子进行MS/MS测定。5种氨基甲酸酯类农药在5~200ng/L范围内线性关系良好,回收率为80%~92%,相对标准偏差均小于10%,方法检出限分别为:异丙威和仲丁威为1.4ng/L,克百威和甲萘威为1.5ng/L,恶虫威为1.6ng/L。该方法适用于水体中氨基甲酸酯类农药残留的检测。 相似文献
32.
A system device using multifunctional conjugated copolymer poly(5-hydroxy-1,4-naphthoquinone-co-hydroxy-2-thioacetic acid-1,4-naphthoquinone) acting both as immobilizing and transducing element for reagentless immunosensor has been constructed. Its functionality was evaluated in an antigen-antibody interaction model using ovalbumin-anti-ovalbumin. It was shown that the system specifically detects via electrochemical signal the antigen-antibody immune interaction in a reagentless context. Comparison to the conventional ELISA technique relevant to performance and sensitivity was presented. 相似文献
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Arnaldi R Banicz K Castor J Chaurand B Cicalò C Colla A Cortese P Damjanovic S David A de Falco A Devaux A Ducroux L En'yo H Fargeix J Ferretti A Floris M Förster A Force P Guettet N Guichard A Gulkanian H Heuser JM Keil M Kluberg L Lourenço C Lozano J Manso F Martins P Masoni A Neves A Ohnishi H Oppedisano C Parracho P Pillot P Poghosyan T Puddu G Radermacher E Ramalhete P Rosinsky P Scomparin E Seixas J Serci S Shahoyan R Sonderegger P Specht HJ Tieulent R Usai G Veenhof R 《Physical review letters》2007,99(13):132302
The NA60 experiment studies muon pair production at the CERN Super Proton Synchrotron. In this Letter we report on a precision measurement of J/psi in In-In collisions. We have studied the J/psi centrality distribution, and we have compared it with the one expected if absorption in cold nuclear matter were the only active suppression mechanism. For collisions involving more than approximately 80 participant nucleons, we find that an extra suppression is present. This result is in qualitative agreement with previous Pb-Pb measurements by the NA50 experiment, but no theoretical explanation is presently able to coherently describe both results. 相似文献
34.
Boundary, a plant fortifier composed of extracts of Sophora flavescens Aiton and brown algae, was tested for control of the leaf miner Tuta absoluta (Meyrick) on tomato (three trials) and of the red spider mite Tetranychus urticae Koch on eggplant (one trial) and for side effects on the whitefly predator Macrolophus pygmaeus (Kambur) (two trials) on tomato and on the thrips predators Orius laevigatus (Fieber) and Amblyseius swirskii Athias-Henriot (two trials) on pepper, all in cold greenhouses in South Italy. Control rates for T. absoluta were moderate (40–70%) in the autumn crop but very high and comparable to those for emamectin benzoate in the spring crops (96–100%). Boundary compared well with abamectin against T. urticae, with near complete control. M. pygmaeus was moderately injured in late autumn, but not in early autumn. At the tested application rate and predator population density Boundary was safe for O. laevigatus and A. swirskii. 相似文献
35.
Azidoethoxyphenylalanine as a Vibrational Reporter and Click Chemistry Partner in Proteins 下载免费PDF全文
Elise M. Tookmanian Prof. Dr. Christine M. Phillips‐Piro Prof. Dr. Edward E. Fenlon Prof. Dr. Scott H. Brewer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(52):19096-19103
An unnatural amino acid, 4‐(2‐azidoethoxy)‐L ‐phenylalanine (AePhe, 1 ), was designed and synthesized in three steps from known compounds in 54 % overall yield. The sensitivity of the IR absorption of the azide of AePhe was established by comparison of the frequency of the azide asymmetric stretch vibration in water and dimethyl sulfoxide. AePhe was successfully incorporated into superfolder green fluorescent protein (sfGFP) at the 133 and 149 sites by using the amber codon suppression method. The IR spectra of these sfGFP constructs indicated that the azide group at the 149 site was not fully solvated despite the location in sfGFP and the three‐atom linker between the azido group and the aromatic ring of AePhe. An X‐ray crystal structure of sfGFP‐149‐AePhe was solved at 1.45 Å resolution and provides an explanation for the IR data as the flexible linker adopts a conformation which partially buries the azide on the protein surface. Both sfGFP‐AePhe constructs efficiently undergo a bioorthogonal strain‐promoted click cycloaddition with a dibenzocyclooctyne derivative. 相似文献
36.
Dinorah Gambino Mariana FernándezDiego Santos Gustavo A. EtcheverríaOscar E. Piro Fernando R. PavanClarice Q.F. Leite Isabel TomazFernanda Marques 《Polyhedron》2011,30(7):1360-1366
In the search for gallium bioactive compounds five Ga(III) complexes, [GaIII(L-H)2](NO3), with tridentate salicylaldehyde semicarbazone derivatives as ligands (L) have been synthesized and characterized in the solid state and in solution by different techniques. The crystal structure of [GaIII(L4-H)2](NO3)·2H2O, where L4 is 3-ethoxysalicylaldehyde semicarbazone, was solved by X-ray diffraction methods. The gallium(III) ion is in a distorted octahedral environment, coordinated to two nearly planar and mutually perpendicular 3-ethoxysalicylaldehyde semicarbazonato anions acting as tridentate ligands through their phenol and carbonyl oxygen atoms and their azomethine nitrogen atom. Their biological potential has been explored by evaluating their activity on Mycobacterium tuberculosis, causative agent of tuberculosis, and their cytotoxicity on tumor cell lines. Three different human tumor cell lines were selected that show different degrees of resistance to metallodrugs: ovarian A2780 (low resistance), breast MCF7 (medium resistance) and prostate PC3 (high resistance) cells. Although the complexes have not shown activity on M. tuberculosis, complexation with gallium has led to the enhancement of the cytotoxic potencies of the organic compounds. Those complexes that contain a bromide substituent at the phenolate ring have shown the highest cytotoxicities. In particular, [GaIII(L2-H)2](NO3), where L2 is 5-bromosalicylaldehyde semicarbazone,·has shown a remarkable cytotoxicity on A2780 tumor cell line with an IC50 value of the same order than cisplatin (IC50 Ga-L2 = 2.4 ± 0.3 μM; IC50 cisplatin = 2.0 ± 0.1 μM, 72 h incubation at 37 °C). Interestingly, this complex has also shown moderate cytotoxicity against MCF7 and PC3 cells (IC50 MCF7 = 30 ± 6; IC50 PC3 = 18 ± 3 μM). Therefore, this gallium compound could be considered a promising wide spectrum potential anti-tumor agent. 相似文献
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在水溶液条件下以六缺位的[H2P2W12O48)]12-和Eu髥为反应前躯体得到了1个新的多金属氧酸盐化合物[Eu3(H2O)17(α2-HP2W17O61)].5H2O(1),对其进行了元素分析、红外光谱、热重、荧光等表征,并用X-射线单晶衍射测定了它的晶体结构。化合物1含有双支撑的多阴离子簇[{Eu(H2O)7}2{Eu(H2O)3(α2-P2W17)}2]8-,并进一步通过Eu髥连接形成了延c轴方向的一维链。室温条件下的荧光光谱研究表明:化合物1显示了强的红光发射。 相似文献
40.
WANG Zhi-xin HOU Yi HAN Wei WANG Kai-chen GUO Bao-feng LIU Ying CHANG Xi-hua WANG Wei-hua NA Wan-li KONG Xiang-bo ZHAO Xu ZHANG Ling 《高等学校化学研究》2011,27(1):94-98
Renal cell carcinoma is the most common cancer of the kidney, and resistant to traditional therapies. The aim of this study is to investigate the effects of hydroxyapatite nanoparticles on human renal cell carcinoma 786-0 cells. Cell proliferation was assessed with an 3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyltetrazolium bromide(MTT) staining kit. The apoptosis assay was assessed with an FITC Annexin V Apoptosis Detection Kit. Caspase-3 and caspase-12 were detected by immunocytochemical staining and semi-qua... 相似文献