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deep eutectic solvent

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https://www.readbyqxmd.com/read/30333712/self-assembled-porphyrazine-nucleosides-on-dna-templates-highly-fluorescent-chromophore-arrays-and-sizing-forensic-tandem-repeat-sequences
#1
Mariia V Ishutkina, Alice R Berry, Rohanah Hussain, Olga G Khelevina, Giuliano Siligardi, Eugen Stulz
The formation of chromophore arrays using a DNA templating approach leads to the creation of supramolecular assemblies, where the optical properties of the overall system can be fine-tuned to a large extent. In particular, porphyrin derivatives have been shown to be versatile building blocks; mostly covalent chemistry was used for embedding the units into DNA strands. Self-assembly of porphyrin modified nucleosides, on the other hand, has not been investigated as a simplified approach. We report on the synthesis of a magnesium(II) tetraaza porphine (MgTAP) coupled to deoxyuridine, and array formation on DNA templates which contain well-defined oligo(dA) segments showing strong fluorescence enhancement which is significantly larger than that with a Zn-porphyrin...
September 30, 2018: European Journal of Organic Chemistry
https://www.readbyqxmd.com/read/30328848/nanoscopic-structures-and-molecular-interactions-leading-to-a-dystectic-and-two-eutectic-points-in-emim-cl-urea-mixtures
#2
Ulrike Cerajewski, Jennica Träger, Selgar Henkel, Andreas H Roos, Martin Brehm, Dariush Hinderberger
Deep eutectic solvents (DES) are a novel class of ionic liquid-based solvents, combining an organic salt and a hydrogen bond acceptor (HBA) at specific molar ratios. The resulting DES mixtures often have strongly depressed freezing points and feature properties well-known for ionic liquids as non-classical solvents. In this study, mixtures of 1-ethyl-3-methylimidazolium chloride ([EMIm][Cl]) and urea are investigated at different molar ratios mainly via electron paramagnetic resonance (EPR) spectroscopy on chemical environment-specific nitroxide-based spin probes, aided by differential scanning calorimetry (DSC) to obtain insights into the structure, dynamics, and molecular processes on the nanoscale...
October 17, 2018: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/30324359/green-synthesis-of-carbon-nanotubes-reinforced-molecularly-imprinted-polymer-composites-for-drug-delivery-of-fenbufen
#3
Xin-Lu Liu, Hong-Fei Yao, Mei-Hong Chai, Wei He, Yan-Ping Huang, Zhao-Sheng Liu
The facile fabrication of single-walled carbon nanotubes (SWCNTs)-doping molecularly imprinted polymer (MIP) nanocomposite-based binary green porogen system, room-temperature ionic liquids (RTILs), and deep eutectic solvents (DESs) was developed for drug delivery system. With fenbufen (FB) as template molecule, 4-vinylpyridine (4-VP) was used as functional monomer, ethylene glycol dimethacrylate as cross-linking monomer, and 1-butyl-3-methylimidazoliumtetrafluoroborate and choline chloride/ethylene glycol as binary green solvent, in the presence of SWCNTs...
October 15, 2018: AAPS PharmSciTech
https://www.readbyqxmd.com/read/30314683/emulsification-microextraction-of-amphetamine-and-methamphetamine-in-complex-matrices-using-an-up-to-date-generation-of-eco-friendly-and-relatively-hydrophobic-deep-eutectic-solvent
#4
Maryam Rajabi, Nooshin Ghassab, Maryam Hemmati, Alireza Asghari
In this study, a new extraction medium based on a quite bio-compatible and bio-degradable deep eutectic solvent comprising choline chloride and phenylethanol (ChCl: Ph-ETOH) was simply and cheaply synthesized at room temperature. At the next step, it was effectively utilized at the service of air agitated-emulsification microextraction (AA-EME) of two major amphetamine-type stimulants (ATSs) in human plasma and pharmaceutical wastewater pursued by high performance liquid chromatography-ultraviolet detection (HPLC-UV)...
October 9, 2018: Journal of Chromatography. A
https://www.readbyqxmd.com/read/30307230/a-comparison-of-choline-urea-and-choline-oxalic-acid-deep-eutectic-solvents-at-338-k
#5
Mark Gilmore, Leila M Moura, Adam H Turner, Małgorzata Swadźba-Kwaśny, Samantha K Callear, Jade A McCune, Oren A Scherman, John D Holbrey
1:2 choline chloride:urea and 1:1 choline chloride:oxalic acid deep eutectic solvents are compared at 338 K using liquid-phase neutron diffraction with H/D isotopic substitution to obtain differential neutron scattering cross sections and fitting of models to the experimental data using Empirical Potential Structure Refinement. In comparison to the previously reported study of choline chloride:urea at 303 K, we observed significant weakening and lengthening of choline-OH⋯Cl- and choline-OH⋯hydrogen-bond acceptor correlations...
May 21, 2018: Journal of Chemical Physics
https://www.readbyqxmd.com/read/30298877/the-peculiar-effect-of-water-on-ionic-liquids-and-deep-eutectic-solvents
#6
REVIEW
Chunyan Ma, Aatto Laaksonen, Chang Liu, Xiaohua Lu, Xiaoyan Ji
Ionic liquids (ILs) and deep eutectic solvents (DESs) have been suggested as eco-friendly alternatives to organic solvents. A trace amount of water is often unavoidable as impurity, and water is also added on purpose to reduce their problematically high viscosity and lower their high price. Understanding the distinct effects of water on the properties of ILs/DESs is highly important. In this review, we collect published experimental and theoretical results for IL/DES-H2O systems at varied water concentrations and analyze them...
October 9, 2018: Chemical Society Reviews
https://www.readbyqxmd.com/read/30297853/a-natural-deep-eutectic-solvent-formulated-to-stabilize-%C3%AE-lactam-antibiotics
#7
Belén Olivares, Fabián Martínez, Lina Rivas, Cristian Calderón, José M Munita, Paola R Campodonico
β-lactam antibiotics, such as penicillin share a very unstable chemical structure. In water-based solutions, such as those used for clinical applications, the β-lactam ring is readily opened due to a nucleophilic or electrophilic attack, leading to the loss of antimicrobial activity. Since the achievement and maintenance of optimum therapeutic levels of β-lactam antibiotics is critical for the resolution of many infectious clinical situations, and to avoid antibiotic resistance generation, the design of new non-aqueous dosage forms is urgent...
October 8, 2018: Scientific Reports
https://www.readbyqxmd.com/read/30296092/shear-viscosity-computed-from-the-finite-size-effects-of-self-diffusivity-in-equilibrium-molecular-dynamics
#8
Seyed Hossein Jamali, Remco Hartkamp, Christos Bardas, Jakob Söhl, Thijs J H Vlugt, Othonas A Moultos
A method is proposed for calculating the shear viscosity of a liquid from finite-size effects of self-diffusion coefficients in Molecular Dynamics simulations. This method uses the difference in the self-diffusivities, computed from at least two system sizes, and an analytic equation to calculate the shear viscosity. To enable the efficient use of this method, a set of guidelines is developed. The most efficient number of system sizes is two and the large system is at least four times the small system. The number of independent simulations for each system size should be assigned in such a way that 50%-70% of the total available computational resources should be allocated to the large system...
October 8, 2018: Journal of Chemical Theory and Computation
https://www.readbyqxmd.com/read/30284000/selective-extraction-of-3-4-dihydroxybenzoic-acid-in-ilex-chinensis-sims-by-meticulous-mini-solid-phase-microextraction-using-ternary-deep-eutectic-solvent-based-molecularly-imprinted-polymers
#9
Guizhen Li, Kyung Ho Row
A ternary deep eutectic solvent (TDES) was used as both template and functional monomer in the synthesis of TDES-based molecularly imprinted polymers (TDES-MIPs). A meticulous miniaturized solid-phase microextraction (mini-SPME) method followed by high-performance liquid chromatography (HPLC) were used for the optimal speciation of 3,4-dihydroxybenzoic acid (3,4-DHBA) in the needle of a syringe system with response surface methodology (RSM). Under the optimal conditions for the determination of 3,4-DHBA (amount of adsorbent (2 mg), sample volume (1 mL), cycles for adsorption and desorption (6)), the actual extraction amount was 8...
October 3, 2018: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/30278889/natural-deep-eutectic-solvents-mediated-extractions-the-way-forward-for-sustainable-analytical-developments
#10
REVIEW
María de Los Ángeles Fernández, Joana Boiteux, Magdalena Espino, Federico J V Gomez, María Fernanda Silva
The concept of sustainable development has impacted in analytical chemistry changing the way of thinking processes and methods. It is important for analytical chemists to consider how sample preparation can integrate the basic concepts of Green Chemistry. In this sense, the replacement of traditional organic solvents is of utmost importance. Natural Deep Eutectic Solvents (NADES) have come to light as a green alternative. In the last few years, a growing number of contributions have applied these natural solvents proving their efficiency in terms of extraction ability, analyte stabilization capacity and detection compatibility...
December 14, 2018: Analytica Chimica Acta
https://www.readbyqxmd.com/read/30278663/dielectric-relaxation-in-acetamide-urea-deep-eutectics-and-neat-molten-urea-origin-of-time-scales-via-temperature-dependent-measurements-and-computer-simulations
#11
Kallol Mukherjee, Suman Das, Ejaj Tarif, Anjan Barman, Ranjit Biswas
Dielectric relaxation (DR) measurements in the frequency window 0.2 ≤ ν(GHz) ≤ 50 for deep eutectic solvents (DESs) made of acetamide (CH3 CONH2 ) and urea (NH2 CONH2 ) with the general composition, [ f CH3 CONH2 + (1 - f ) NH2 CONH2 ] at f = 0.6 and 0.7, reveal three distinct relaxation time scales-τ1 ∼ 120 ps, τ2 ∼ 40 ps, and τ3 ∼ 5 ps. Qualitatively similar time scales have been observed for DR of neat molten urea, whereas the reported DR for neat molten acetamide in the same frequency window reflects two relaxation processes with no trace of ∼100 ps time scale...
September 28, 2018: Journal of Chemical Physics
https://www.readbyqxmd.com/read/30277778/atomistic-insights-into-the-electrochemical-double-layer-of-choline-chloride-urea-deep-eutectic-solvent-a-clustered-interfacial-structuring
#12
Mesfin Haile Mamme, Samuel L C Moors, Herman A Terryn, Johan Deconinck, Jon Ustarroz, Frank De Proft
Green, stable and wide electrochemical window deep eutectic solvents (DESs) are ideal candidates for electrochemical systems. However, despite several studies of their bulk properties, their structure and properties under electrified confinement are barely investigated, which hinders the widespread use of these solvents in electrochemical applications. In this letter, we explore the electrical double layer structure of 1:2 choline chloride-urea (Reline), with a particular focus on the electrosorption of the hydrogen bond donor on a graphene electrode using atomistic molecular dynamics simulations...
October 2, 2018: Journal of Physical Chemistry Letters
https://www.readbyqxmd.com/read/30274692/monolithic-column-with-polymeric-deep-eutectic-solvent-as-stationary-phase-for-capillary-electrochromatography
#13
Rong Wang, Zhenkun Mao, Zilin Chen
A novel monolithic column based on the copolymerization of ethylene dimethacrylate and a deep eutectic solvent (DES), which composed of chlorocholine chloride and itaconic acid, was developed for capillary electrochromatography (CEC). The structure and morphology of the obtained monolithic column was characterized by Fourier transform infrared spectra and scanning electron microscopy, which showed a porous monolithic structure with good permeability. The influence of pH value and acetonitrile content on electroosmotic flow (EOF) of DES-based monolithic column was investigated...
September 26, 2018: Journal of Chromatography. A
https://www.readbyqxmd.com/read/30271772/integrated-process-for-the-enzymatic-production-of-fatty-acid-sugar-esters-completely-based-on-lignocellulosic-substrates
#14
Sascha Siebenhaller, Jennifer Kirchhoff, Frank Kirschhöfer, Gerald Brenner-Weiß, Claudia Muhle-Goll, Burkhard Luy, Fabian Haitz, Thomas Hahn, Susanne Zibek, Christoph Syldatk, Katrin Ochsenreither
Lignocellulose can be converted sustainably to fuels, power and value-added chemicals like fatty acid esters. This study presents a concept for the first eco-friendly enzymatic synthesis of economically important fatty acid sugar esters based on lignocellulosic biomass. To achieve this, beech wood cellulose fiber hydrolysate was applied in three manners: as sugar component, as part of the deep eutectic solvent (DES) reaction system and as carbon source for the microbial production of the fatty acid component...
2018: Frontiers in Chemistry
https://www.readbyqxmd.com/read/30270562/deep-eutectic-solvents-based-extraction-of-polyphenolic-antioxidants-from-onion-allium-cepa-l-peel
#15
Chandra Bhushan T Pal, Girirajsinh C Jadeja
BACKGROUND: Biomass waste including the fruit and vegetable residues pose serious challenge to the environment demanding novel approaches for handling and disposing them in a safer manner. In contrast, they are extremely rich in bioactive components, which are considered to have a beneficial impact on health. This has led to recovering high value compounds from such wastes before finally disposing them. The present investigation reveals the use of green solvents such as eutectic mixtures composed of choline chloride with three different hydrogen bond donors like sucrose (4:1), urea (1:2) and sorbitol (3:1) as extractants for recovering valuable phenolic antioxidants from onion peel...
September 30, 2018: Journal of the Science of Food and Agriculture
https://www.readbyqxmd.com/read/30269222/deep-eutectic-solvent-based-air-assisted-ligandless-emulsification-liquid-liquid-microextraction-for-preconcentration-of-some-heavy-metals-in-biological-and-environmental-samples
#16
Maryam Ezoddin, Navid Lamei, Fatemeh Siami, Khosrou Abdi, Mohammad Ali Karimi
In this study, a deep eutectic solvent (DES) based on air-assisted ligandless emulsification liquid-liquid microextraction method (DES-AA-LL-ELLME) was considered for preconcentration and extraction of some metals (Cd, Ni, Pb and Cu). A 1:1 mixture of the synthesized DES and triethylamine was added as an extractant to extract metal ions in the absence of chelating agent. Tetrahydrofuran as the aprotic solvent provided a turbid state. To disperse the aggregated DES droplets into the aqueous phase, air-assisted was performed...
September 29, 2018: Bulletin of Environmental Contamination and Toxicology
https://www.readbyqxmd.com/read/30268813/in-situ-deep-eutectic-solvent-pretreatment-to-improve-lignin-removal-from-garden-wastes-and-enhance-production-of-bio-methane-and-microbial-lipids
#17
Qiang Yu, Lei Qin, Yunyun Liu, Yongming Sun, Huijuan Xu, Zhongming Wang, Zhenhong Yuan
Biomass pretreatment can improve the conversion efficiency of bioenergy production. Liquid hot water (LHW) pretreatment is a truly green pretreatment due to its zero chemical use, but has the disadvantages of low lignin removal and pseudo-lignin formation. A modified liquid hot water (MLHW) process based on in situ synthesis of deep eutectic solvent (DES) could efficiently improve delignification of Roystonea regia leaves (LR) and leaf sheaths (LSR). LSR was less recalcitrant than LR, and its characteristics of higher porosity (34...
September 13, 2018: Bioresource Technology
https://www.readbyqxmd.com/read/30262060/poly-itaconic-acid-grafted-silica-stationary-phase-prepared-in-deep-eutectic-solvents-and-its-unique-performance-in-hydrophilic-interaction-chromatography
#18
Yongxing Hu, Tianpei Cai, Haijuan Zhang, Jia Chen, Zuguang Li, Hongdeng Qiu
In this study, a new stationary phase based on poly(itaconic acid)-grafted silica (Sil-PIA) were synthesized in deep eutectic solvents (DESs) and characterized in detail. Itaconic acid was homopolymerized on silica via surface radical chain-transfer reaction using DESs as a new kind of green solvents. Sil-PIA were obtained and characterized by Fourier transform infrared spectroscopy, elemental analysis and scanning electron microscopy. The retention changes of nucleosides and nucleobases on the columns was studied under different chromatographic conditions including salt concentration, acetonitrile content, mobile phase pH, and column temperature...
January 1, 2019: Talanta
https://www.readbyqxmd.com/read/30251861/deep-eutectic-solvent-induced-structural-transition-of-microemulsions-explored-with-small-angle-x-ray-scattering
#19
Mina Sakuragi, Shinsuke Tsutsumi, Katsuki Kusakabe
Microemulsions (MEs) containing deep eutectic solvents (DESs) and water in the inner phase for use in transdermal delivery of poorly soluble drugs were prepared using a mixture of polyoxyethylene sorbitan monooleate (Tween-80) and sorbitan laurate (Span-20) as surfactants. We investigated the effects of the ratios of surfactant (Tween-80/Span-20) and solvents (DES components/water) on the ME structure determined by the analysis of small angle X-ray scattering (SAXS) profiles with the core-corona model. Tween-80 with an unsaturated long alkyl chain induced a structural transition of MEs from a sphere to a cylinder...
September 25, 2018: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/30241813/versatile-acid-base-sustainable-solvent-for-fast-extraction-of-various-molecular-weight-chitin-from-lobster-shell
#20
Shu Hong, Yang Yuan, Qiuru Yang, Ping Zhu, Hailan Lian
Deep eutectic solvent (DES) prepared from choline chloride and four organic acid were evaluated for the extraction of chitin from lobster shell. It was found that the purity of chitins extracted with DESs was related to acid used. Purity of chitin extracted with choline chloride-malonic acid was the highest. Chitins extracted through DES treatment results in various molecular weight, which is associated with type of acid and temperature used during the treatment. For instance, chitin produced by malonic acid at 50 °C and 100 °C results in molecular weight of 312 KDa and 199 KDa respectively, whereas it extracted with malic acid at 100 °C results in 91 KDa...
December 1, 2018: Carbohydrate Polymers
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