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111.
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In this work, a sensitive label-free impedimetric hCG-immunosensor was constructed by using a commercial screen-printing carbon ink electrode (namely disposable electrochemical printed chip) as the basis. The carbon ink electrode of DEP chip is modified first by deposition of polypyrrole-pyrole-2-carboxylic acid copolymer and thence hCG antibody immobilization via the COOH groups of pyrrole-2-carboxylic acid, which can serve as a linker for covalent biomolecular immobilization. The experimental results exposed that the designed immunosensor is more sensitive than other previously reported immunosensors, in the case of detection limit and linear range for antigen detection. With optimal fabrication parameters, the detection limit for α-hCG was 2.3 pg/mL in 10 mM phosphate buffer saline (PBS) solution containing 1% bovine serum albumine (BSA). Moreover, the use of inexpensive DEP chip as a basis for these immunosensors will allow for simple instrumentation, disposable and portable at low cost. This work also demonstrates a new approach to develop a sensitive and label-free impedimetric immunosensor based on screen-printed electrode for applications in clinical diagnosis. 相似文献
113.
The enantioselective propargylic alkylation of propargylic esters with aldehydes in the presence of a copper complex and an optically active secondary amine as cocatalysts has been found to give the corresponding propargylic alkylated products in good yields as a mixture of two diastereoisomers with a high enantioselectivity. 相似文献
114.
The enantioselective propargylic amination of propargylic pentafluorobenzoates bearing an alkyl group at the propargylic position with amines in the presence of catalytic amounts of a copper complex and an optically active diphosphine such as BINAP has been found to give the corresponding propargylic amines in good yields with high enantioselectivity. 相似文献
115.
Harada T Nakagawa Y Ogura T Yamada Y Ohe T Miyagawa H 《Journal of chemical information and modeling》2011,51(2):296-305
Insect growth is regulated by the orchestrated event of ecdysteroids and their receptor proteins. Agonists/antagonists of ecdysteroid receptor are predicted to disrupt normal growth, providing good candidates of new insecticides. A database of over 2 million compounds was subjected to a shape-based virtual screening cascade to identify novel nonsteroidal hits similar to the known EcR ligand ponasterone A. Testing revealed micromolar hits against two strains of insect cells. Docking experiments against EcR were used to support the predicted binding mode of these ligands based on their overlay to ponasterone A. 相似文献
116.
Yoshiaki Fukuma 《Journal of Pure and Applied Algebra》2011,215(2):168-184
Let X be a smooth complex projective variety of dimension 3 and let L be an ample line bundle on X. In this paper, we provide a lower bound for h0(m(KX+L)) under the assumption that κ(KX+L)≥0. In particular, we get the following: (1) if 0≤κ(KX+L)≤2, then h0(KX+L)>0 holds. (2) If κ(KX+L)=3, then h0(2(KX+L))≥3 holds. Moreover we get a classification of (X,L) with κ(KX+L)=3 and h0(2(KX+L))=3 or 4. 相似文献
117.
Shiraishi T Kitamura Y Ueno Y Kitade Y 《Chemical communications (Cambridge, England)》2011,47(9):2691-2693
We synthesised aryl acetylene derivatives as versatile probes for labelling of oligonucleotides. RNA oligomers bearing an aryl acetylene molecule rapidly reacted with benzylazide derivatives under ligand-free click reaction conditions. 相似文献
118.
Size selective inclusion of organic molecules into pillared carbons accompanied by large interlayer expansions was observed for the first time. In order to achieve this, the distance between two adjacent pillars should be between 0.36 and 0.40 nm and they should align in the same direction. 相似文献
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