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121.
Detection of p53 Gene by Using Genomagnetic Assay Combined with Carbon Nanotube Modified Disposable Sensor Technology 下载免费PDF全文
Electrochemical monitoring of DNA hybridization related to p53 gene sequence was investigated using genomagnetic assay combined with single walled carbon nanotube (SWCNT) modified pencil graphite electrodes (PGEs). The hybridization was performed either at magnetic beads (MB) surface or in solution. The enhanced guanine signal was obtained using SWCNT‐PGEs compared to one obtained by unmodified PGEs. The selectivity of genomagnetic assay was tested under optimum conditions. The DLs were calculated as 0.88 µM and 0.11 µM for hybridization performed at MB surface and solution, respectively. This selective, practical and cost effective genomagnetic assay combined with SWCNT‐PGEs is reported herein for the first time. 相似文献
122.
Electrochemical Activity of Wedelolactone and Probing its Interaction with DNA Using Voltammetry at a Carbon Electrode 下载免费PDF全文
Wedelolactone (WLA) is a polyphenolic coumestan derivative found in extracts of plants used in traditional medicine. Due to its cytostatic activity, WLA is one of natural compounds tested as potential anticancer drugs. In this work we for the first time studied electrochemical properties of WLA using cyclic (CV) and square‐wave (SWV) voltammetry at the basal‐plane pyrolytic graphite electrode. A reversible pair of peaks, corresponding to catechol/o‐benzoquinone redox system, was observed using CV around 0.275 V vs. Ag|AgCl|3 M KCl reference electrode. Measurements of SWV signal of WLA in the presence of single‐ or double‐stranded DNA suggested a weak interaction without evident preference for double‐stranded DNA. An indirect assay, employing electroactive DNA intercalator doxorubicin as competitor, confirmed absence of intercalative DNA binding of WLA. 相似文献
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Jiríčková Kristína Gál Miroslav Krahulec Ján Híveš Ján 《Monatshefte für Chemie / Chemical Monthly》2015,146(5):755-759
Monatshefte für Chemie - Chemical Monthly - Basic biochemical properties such as Michaelis constant (K M), turnover number (k cat), and the ratio between these two kinetic parameters of enzyme... 相似文献
126.
The Identification of a Novel Highly Condensed Pentacyclic Heteroaromatic Ring System 1,3,5,5b,6,8,10,10b‐Octaazacyclopenta[h,i]Aceanthrylene and its Application in the Synthesis of 5,7‐Substituted Pyrazolo[4,3‐d]Pyrimidines 下载免费PDF全文
Libor Havlíček Daniela Moravcová Vladimír Kryštof Miroslav Strnad 《Journal of heterocyclic chemistry》2015,52(3):669-673
Pyrazolo[4,3‐d]pyrimidines are of interest as potential kinase inhibitors. This article describes the formation of a novel highly conjugated, condensed, centrosymmetric heteroaromatic compound, 4,9‐dichloro‐2,7‐diisopropyl‐1,3,5,5b,6,8,10,10b‐octaazacyclopenta[h,i]aceanthrylene ( 3 ), during the chlorination of 5,7‐dihydroxypyrazolo[4,3‐d]pyrimidine ( 1 ) with phenylphosphonic dichloride. The nucleophilic attack of benzylamine on 3 afforded N‐benzyl‐5‐chloro‐3‐isopropyl‐1H‐pyrazolo[4,3‐d]pyrimidin‐7‐amine ( 6 ), which was further substituted to yield a pyrazolo[4,3‐d]pyrimidine analogue of roscovitine, a well‐known cyclin‐dependent kinase inhibitor. 相似文献
127.
Based on rational design of the transition state analog inhibitors of glycosyltransferases, four model glycomimetics of this type, viz. benzyl 2-thio-α-dfructofuranoside 1-diethylphosphate (XIa), its β-anomer (XIb), and their ethyl 2-thio analogs — α-anomer (XIIa) and β-anomer (XIIb), were synthesized. In addition, fourteen precursors arising during the synthesis of the desired final model compounds (XI and XII), partially or fully acetylated benzyl and/or ethyl 2-thiofructofuranoside 1-diethyl phosphates, were isolated and characterized with the aim to prepare complete series of glycomimetics, representing donor UDP-GlcNAc designated for biological assays on human GnT’s, viz. GnT-I, Core2GnT, and GnT-V. 相似文献
128.
Vasylyna Lavra Yaroslav Bazel Miroslav Badida Vasil Andruch 《International journal of environmental analytical chemistry》2015,95(3):217-224
A novel and simple procedure for determination of anionic surfactants has been developed. The method is based on the reaction of sodium dodecyl sulphate (SDS) with Astra Phloxine FF reagent at pH 3–8, followed by liquid–liquid microextraction of the formed ion associate into an organic phase containing a mixture of carbon tetrachloride and dichloroethane (4:1, v/v) and subsequent UV-Vis detection at 555 nm. The calibration plot was linear in the range 0.006–0.29 mg L?1 of SDS. The limit of detection (LOD), calculated based on 3s, is 0.002 mg L?1. The method was applied to the determination of anionic surfactants in real wastewater samples. 相似文献
129.
Frontispiece: Hydrogenated Graphenes by Birch Reduction: Influence of Electron and Proton Sources on Hydrogenation Efficiency,Magnetism, and Electrochemistry 下载免费PDF全文
130.
Organic coatings containing zinc are amply used for the protection of metals, particularly steel structures. Ways to reduce the zinc content in the coating materials are sought for environmental and financial reasons. Our previous work (Kohl, Prog Org Coat 77:512–517, 2014; Kohl and Kalendová, Mater Sci Forum 818: 171–174, 2015a) suggested that one of the options consists in the use of conductive polymers in the formulation of the zinc coatings. The benefits of conductive polymers include nontoxicity, high stability, electric conductivity and redox potential. Previously we focussed on the effect of conductive polymers added to the organic coatings so as to complete the zinc volume concentration to 67%. The anticorrosion efficiency of the organic coatings was found to improve with increasing polyaniline phosphate or polypyrrole concentrations. Zinc content reduction in the system, however, did not attain more than 5%. The present work focusses on systems where the organic coatings are prepared with zinc having a pigment volume concentration PVC = 50%. Zinc content reduction in the system attains up to 20%. This work examines the mechanical and anticorrosion properties of the organic coatings with reduced zinc contents. The present work was devoted to the feasibility of using of conductive polymers in the formulation of coatings with reduced zinc contents. The conductive polymers included polyaniline, polypyrrole and poly(phenylenediamine); these were synthesised and characterised using physico-chemical methods. Polyphenylenediamine as a potential corrosion inhibitor has not been paid adequate attention so far. Subsequently, organic coatings with reduced zinc contents and containing the pigments at 0.5, 1 and 3% volume concentrations were formulated. The coatings were subjected to mechanical tests and accelerated corrosion tests to assess their mechanical and corrosion resistance. The corrosion resistance of the organic coatings was also studied by linear polarisation. The results of the mechanical tests, accelerated corrosion tests and linear polarisation measurements indicate that the organic coating properties get affected by the conductive polymer type as well as by the pigment volume concentration. The important finding is that the use of conductive polymers in coatings with reduced zinc contents was beneficial in all cases. 相似文献