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991.
Ben-Barak Ido Schneier Dan Kamir Yosef Goor Meital Golodnitsky Diana Peled Emanuel 《Journal of Solid State Electrochemistry》2022,26(1):183-193
Journal of Solid State Electrochemistry - We present the application of drop-on-demand (DoD) dispensing technology for printing of silicon-based anodes. We show that the DoD printing technique is... 相似文献
992.
Mayorov Pavel Asabina Elena Zhukova Anna Osaulenko Diana Pet’kov Vladimir Lavrenov Dmitry Kovalskii Andrey Fionov Alexander 《Research on Chemical Intermediates》2021,47(9):3645-3659
Research on Chemical Intermediates - Aliphatic alcohols C1–C4 can serve as raw material for the production of essential organic products, such as olefins, aldehydes, ketones and ethers. For... 相似文献
993.
We report the application of an electrochemical sensor based on gold-copper metal-organic framework immobilized on the surface of a glassy carbon electrode to the detection of captopril (CAP), an angiotensin-converting enzyme inhibitor. Cyclic voltammetric studies showed that the joint action of gold nanoparticles and copper-1,3,5-benzenetricarboxylate (Cu−BTC) enhanced the electrochemical response to the Cu-captopril complex that is adsorbed onto the surface of the electrode. Release of gold nanoparticles from Au@Cu−BTC not only increased the conductivity of the electrode but also provided a more favorable environment for the deposition of reduced Cu that is catalytically renewed on the electrode surface. The anodic current of the Cu(II)−CAP oxidation peak varied linearly within two concentration ranges, namely 0.5 to 7.0 μmol L−1 and 10 to 2500 μmol L−1, with a limit of detection of 0.047 μmol L−1. The mean recovery for the determination of captopril in commercial tablets was 100.3 % suggesting that the method has considerable potential for future industrial applications. 相似文献
994.
Rezeda A. Ishkaeva Ilyas S. Nizamov Dmitriy S. Blokhin Elizaveta A. Urakova Vladimir V. Klochkov Ilnar D. Nizamov Bulat I. Gareev Diana V. Salakhieva Timur I. Abdullin 《Molecules (Basel, Switzerland)》2021,26(10)
Phosphorus species are potent modulators of physicochemical and bioactive properties of peptide compounds. O,O-diorganyl dithiophoshoric acids (DTP) form bioactive salts with nitrogen-containing biomolecules; however, their potential as a peptide modifier is poorly known. We synthesized amphiphilic ammonium salts of O,O-dimenthyl DTP with glutathione, a vital tripeptide with antioxidant, protective and regulatory functions. DTP moiety imparted radical scavenging activity to oxidized glutathione (GSSG), modulated the activity of reduced glutathione (GSH) and profoundly improved adsorption and electrooxidation of both glutathione salts on graphene oxide modified electrode. According to NMR spectroscopy and GC–MS, the dithiophosphates persisted against immediate dissociation in an aqueous solution accompanied by hydrolysis of DTP moiety into phosphoric acid, menthol and hydrogen sulfide as well as in situ thiol-disulfide conversions in peptide moieties due to the oxidation of GSH and reduction of GSSG. The thiol content available in dissolved GSH dithiophosphate was more stable during air oxidation compared with free GSH. GSH and the dithiophosphates, unlike DTP, caused a thiol-dependent reduction of MTS tetrazolium salt. The results for the first time suggest O,O-dimenthyl DTP as a redox modifier for glutathione, which releases hydrogen sulfide and induces biorelevant redox conversions of thiol/disulfide groups. 相似文献
995.
Since neurodevelopmental disorders (NDDs) influence more than 3% of children worldwide, there has been intense investigation to understand the etiology of disorders and develop treatments. Although there are drugs such as aripiprazole, risperidone, and lurasidone, these medications are not cures for the disorders and can only help people feel better or alleviate their symptoms. Thus, it is required to discover therapeutic targets in order to find the ultimate treatments of neurodevelopmental disorders. It is suggested that abnormal neuronal morphology in the neurodevelopment process is a main cause of NDDs, in which the serotonergic system is emerging as playing a crucial role. From this point of view, we noticed the correlation between serotonin receptor subtype 7 (5-HT7R) and NDDs including autism spectrum disorder (ASD), fragile X syndrome (FXS), and Rett syndrome (RTT). 5-HT7R modulators improved altered behaviors in animal models and also affected neuronal morphology via the 5-HT7R/G12 signaling pathway. Through the investigation of recent studies, it is suggested that 5-HT7R could be a potential therapeutic target for the treatment of NDDs. 相似文献
996.
Dr. William G. Hale Tommy Y. Zhao Diana Choi Maria-Jose Ferrer Bochuan Song Hanqin Zhao Prof. Helena E Hagelin-Weaver Prof. Clifford R. Bowers 《Chemphyschem》2021,22(9):822-827
Side-arm hydrogenation (SAH) by homogeneous catalysis has extended the reach of the parahydrogen enhanced NMR technique to key metabolites such as pyruvate. However, homogeneous hydrogenation requires rapid separation of the dissolved catalyst and purification of the hyperpolarised species with a purity sufficient for safe in-vivo use. An alternate approach is to employ heterogeneous hydrogenation in a continuous-flow reactor, where separation from the solid catalysts is straightforward. Using a TiO2-nanorod supported Rh catalyst, we demonstrate continuous-flow parahydrogen enhanced NMR by heterogeneous hydrogenation of a model SAH precursor, propargyl acetate, at a flow rate of 1.5 mL/min. Parahydrogen gas was introduced into the flowing solution phase using a novel tube-in-tube membrane dissolution device. Without much optimization, proton NMR signal enhancements of up to 297 (relative to the thermal equilibrium signals) at 9.4 Tesla were shown to be feasible on allyl-acetate at a continuous total yield of 33 %. The results are compared to those obtained with the standard batch-mode technique of parahydrogen bubbling through a suspension of the same catalyst. 相似文献
997.
Gangabadage CS Najda A Bogdan D Wijmenga SS Tessari M 《The journal of physical chemistry. B》2008,112(14):4242-4245
Sodium dodecyl sulfate (SDS) micelles provide ideal mimetic media for high-resolution NMR studies of membrane proteins and proteins or peptides interacting with micellar aggregates. (15)N NMR relaxation of the backbone amides of a protein-SDS complex has been measured under different experimental conditions. The rotational diffusion time of this complex has been found highly sensitive to detergent and NaCl concentrations. A comparison with calculated rotational diffusion times of protein-free SDS micelles under the same conditions suggests that the size of both aggregates must follow a similar functional dependence on detergent/NaCl concentration. 相似文献
998.
Desiderio C De Rossi A Inzitari R Mancinelli A Rossetti DV Castagnola M Messana I 《Analytical and bioanalytical chemistry》2008,390(6):1637-1644
A capillary electrophoresis (CE) method coupled to electrospray ionization ion trap tandem mass spectrometry (ESI-IT-MS/MS)
is described for the rapid analysis of carnitine, acetylcarnitine, and propionylcarnitine in human plasma. Optimization of
the procedure was achieved by a reduced sample pretreatment and after examining several physicochemical parameters that influence
both the CE separation and the MS analytes detection. The analysis of total carnitine in human plasma after hydrolysis of
short-chain metabolites is also shown. The analysis of carnitine and metabolites was obtained in less than 10 min using a
200 mM ammonium formate buffer, pH 2.5, with high sensitivity and specificity using the MS detection in product ion scan mode.
The method was tested for quantitative recovery using dialyzed human plasma as matrix and showed linearity in the concentrations
ranges 20–160, 1–32, and 0.25–8 μM for carnitine, acetylcarnitine, and propionylcarnitine with (squared) correlation coefficients
of 0.9984, 0.9995, and 0.9991, respectively. The intraday and intermediate analysis repeatability and accuracy are within
15% of relative standard deviation (RSD) at low, medium, and high concentration and within/or slight exceeding 20% at the
lower limit of quantitation (LLOQ). The method is sensitive for determining carnitine and its metabolites in human plasma
with high specificity. 相似文献
999.
Lyudmila A. Belyakova Oleksandra M. Shvets Diana Yu. Lyashenko 《Central European Journal of Chemistry》2008,6(4):581-591
The present work investigates the adsorptive interactions of Hg(II) ions in aqueous medium with hydroxylated silica, aminopropylsilica
and silica chemically modified by β-cyclodextrin. Batch adsorption studies were carried out with various agitation times and
mercury(II) concentrations. The maximum adsorption was observed within 15–30 min of agitation. The kinetics of the interactions,
tested with the model of Lagergren for pseudo-first and pseudo-second order equations, showed better agreement with first
order kinetics (k1 = 3.4 ± 0.2 to 5.9 ± 0.3 min−1). The adsorption data gave good fits with Langmuir isotherms. The results have shown that β-cyclodextrin-containing adsorbent
has the largest adsorption specificity to Hg(II): K
L
= 4125 ± 205 mmol−1. “β-cyclodextrin-NO3-” inclusion complexes with ratio 1: 1 and super molecules with composition C42H70O35 ⊎ 3 Hg(NO3)2 are formed on the surface of β-cyclodextrin-containing silica.
相似文献
1000.