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51.
Titania layers obtained by a sol-gel technique doped with redox mediator, Meldola’s Blue, were employed for construction of
a new NADH senor. Optimization of preparation process as well as experimental conditions affecting the response of the sensor
were examined. Under optimal conditions NADH could be determined in the wide linear range from 90 to 2300 μM with detection
limit 12 μM and a high sensitivity 12.5 nA μM−1. The usefulness of developed sensor was preliminarily checked in determination of NADH forming during enzymatic oxidation
of ethanol catalyzed by alcohol dehydrogenase (ADH).
相似文献
52.
JPC – Journal of Planar Chromatography – Modern TLC - The lipophilicity of twenty-one N-benzyl-2-azaspiro[4.4]nonaneand [4.5]decane-1,3-dione derivatives, fifteen of which (1–15)... 相似文献
53.
Adrian Badura Dmitrii Guschin Berndt Esper Tim Kothe Sebastian Neugebauer Wolfgang Schuhmann Matthias Rögner 《Electroanalysis》2008,20(10):1043-1047
Photosystem 2 (PS2) that catalyses light driven water splitting in photosynthesis was ‘wired’ to electrode surfaces via osmium‐containing redox polymers based on poly(vinyl)imidazol. The redox polymer hydrogel worked as both immobilization matrix and electron acceptor for the enzyme. Upon illumination, the enzymatic reaction could be switched on and a catalytic current was observed at the electrode. The catalytic current is directly dependent on the intensity of light used for the excitation of PS2. A typical current density of 45 μA cm?2 at a light intensity of 2.65 mW cm?2 could be demonstrated with a significantly improved operational stability. 相似文献
54.
Jolanta Galazka-Friedman 《Hyperfine Interactions》2008,182(1-3):31-44
In this review the properties of iron in various human brain structures (e.g. Substantia nigra, globus pallidus, hippocampus) were analyzed to assess the possibility of initiation of oxidative stress leading to such diseases as Parkinson’s and Alzheimer’s disease, and progressive supranuclear palsy. Our own studies with the use of Mössbauer spectroscopy, electron microscopy and enzyme-linked immuno-absorbent assay (ELISA) were confronted with other methods used in other laboratories. Our results suggest that hippocampus is the most fragile for oxidative stress structure in human brain (the death of nervous cells in hippocampus leads to Alzheimer’s disease). Changes in iron metabolism were also found in substantia nigra (the death of nervous cells of this structure produces Parkinson’s disease) and in globus pallidus (neurodegeneration of this structure causes progressive supranuclear palsy). 相似文献
55.
Infrared spectra of perchlorate, halide and nitrate solutions in acetone are studied. The CO and CCC band frequency changes are discussed in terms of the electronic structure of acetone molecules complexed with cation and anion. The correlation between the shift of the CO and CCC bands and the reactivity of acetone molecules in aldolic condensation reaction is given. An explanation of the anion effect in aldolic condensation is proposed. 相似文献
56.
Microchimica Acta - An accurate and simple indirect method of flame-emission spectrometric determination of small quantities of elemental sulphur and many sulphur compounds, without their prior... 相似文献
57.
58.
59.
Straksys Antanas Kavleiskaja Tatjana Gruskiene Ruta Badokas Kazimieras Sereikaite Jolanta 《Cellulose (London, England)》2022,29(16):8705-8718
Cellulose - The study aimed to propose a new system based on xylan for β-carotene delivery into aqueous environments. The xylan fraction of low molecular weight of... 相似文献
60.
Mathias B. Danielsen Dr. Chenguang Lou Jolanta Lisowiec-Wachnicka Prof. Anna Pasternak Per T. Jørgensen Prof. Jesper Wengel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(6):1368-1379
Off-target effects remain a significant challenge in the therapeutic use of gapmer antisense oligonucleotides (AONs). Over the years various modifications have been synthesized and incorporated into AONs, however, precise control of RNase H-induced cleavage and target sequence selectivity has yet to be realized. Herein, the synthesis of the uracil and cytosine derivatives of a novel class of 2′-deoxy-2′-fluoro-3′-C-hydroxymethyl-β-d -lyxo-configured nucleotides has been accomplished and the target molecules have been incorporated into AONs. Experiments on exonuclease degradation showed improved nucleolytic stability relative to the unmodified control. Upon the introduction of one or two of the novel 2′-fluoro-3′-C-hydroxymethyl nucleotides as modifications in the gap region of a gapmer AON was associated with efficient RNase H-mediated cleavage of the RNA strand of the corresponding AON:RNA duplex. Notably, a tailored single cleavage event could be engineered depending on the positioning of a single modification. The effect of single mismatched base pairs was scanned along the full gap region demonstrating that the modification enables a remarkable specificity of RNase H cleavage. A cell-based model system was used to demonstrate the potential of gapmer AONs containing the novel modification to mediate gene silencing. 相似文献