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201.
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203.
Jeroen Hendrik Vrijsen Emma Van de Reydt Tanja Junkers 《Journal of polymer science. Part A, Polymer chemistry》2020,58(24):3402-3410
Thermoresponsive star polymers were synthesized by copolymerization of water-soluble acrylate monomers, di(ethylene glycol) ethyl ether acrylate (DEGA) and 2-hydroxyethyl acrylate (HEA), in a core-first approach using a modified β-cyclodextrin multifunctional initiator and photo-mediated atom transfer radical polymerization (photoATRP). The controlled character of the polymerization, as well as the formation of statistical star copolymers, was demonstrated. The lower critical solution temperature (LCST) is conveniently tuned by varying the ratio of the two hydrophilic monomers. The cyclodextrin core appears to lead to a lowering of the LCST, and introduction of a hydrophobic pocket via star block copolymer synthesis allowed for further tunability of the cloud point temperature. In the final step, we demonstrate that the star polymers made in here can be used as facile carriers and solubilizers for hydrophobic compounds, highlighting their applicability in the biomedical field. 相似文献
204.
Emma Petiot Frantz Fournier Cécile Gény Hervé Pinton Annie Marc 《Applied biochemistry and biotechnology》2010,160(6):1600-1615
The paper proposes a rapid screening method for a first step improvement of an animal component-free medium dedicated to the
growth of the anchorage-dependent Vero cell line. A new, rapid, and non-invasive technique is presented to specifically monitor
cultures of adherent cells in 96-well plates. The operating conditions of an image analyzer are adapted to take into account
the decrease of cell size when the attached cell density increases. An experimental design is carried out to assess the influence
of ten component groups in the original medium. Two groups including protein extracts, growth factor, insulin, glucose, and
pyruvate show significant positive effects. The groups with vitamins and molecules related to nitrogenous bases display a
less pronounced influence. The mixture of amino acids, B1 vitamin, magnesium sulfate, and sodium phosphate as well as the couple sodium citrate and ferric chloride lead to a downward
trend. The screening results are proved to be scalable in stirred cultures with cells on microcarriers. An improved serum-free
medium, with some component groups being removed or added, can be rapidly formulated to reach respectively similar or 1.6
times higher cell density than in the original medium. The results from this global approach could be helpful to further focus
experiments on identified medium components. 相似文献
205.
Konstantin V. Purtov Valentin N. Petushkov Mikhail S. Baranov Konstantin S. Mineev Natalja S. Rodionova Zinaida M. Kaskova Aleksandra S. Tsarkova Alexei I. Petunin Vladimir S. Bondar Emma K. Rodicheva Svetlana E. Medvedeva Yuichi Oba Yumiko Oba Alexander S. Arseniev Sergey Lukyanov Josef I. Gitelson Ilia V. Yampolsky 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(28):8113-8113
206.
Emma L. McConnell Juned Tutas Mohamed A. M. Mohamed Douglas Banning Abdul W. Basit 《Cellulose (London, England)》2007,14(1):25-34
Amylose, a plant polysaccharide from starch, can be combined with ethylcellulose to produce a film coating capable of effecting colon specific drug release from a dosage form through bacterial fermentation of the amylose component. Ethylcellulose is present in the system as a structuring agent in the form of the aqueous dispersion Surelease® grade EA-7100. There are, however, two other grades of Surelease® (E-7-7050 and E-7-19010), which vary slightly in terms of their composition. The aim of the study was to establish whether these grades differ in their drug release profiles, when used as a film coat, either as one-component coatings, or in combination with amylose. The dissolution profiles of Surelease® coated pellets were investigated and it was found that there was no difference between the grades when used as coating materials on their own. However, when used in combination with amylose, it was found that grade EA-7100 showed retardation of drug release in simulated upper gastro-intestinal (GI) conditions, whereas grades E-7-7050 and E-7-19010 did not limit the release to the same extent. E-7-19010 showed very poor controlled release properties when combined with amylose. These differences could not be attributed to the minimum film forming temperature (MFT) of the coating formulation, which was found to be independent of the grade of Surelease®. It was also confirmed that the film coated pellets prepared from amylose and EA-7100 showed good release in human faecal slurry, i.e. simulated colonic conditions. It was concluded that the grades of Surelease®, when combined with amylose, are not interchangeable. 相似文献
207.
Sebestyén Zoltán Jakab Emma Domán Andrea Bokrossy Péter Bertóti Imre Madarász János László Krisztina 《Journal of Thermal Analysis and Calorimetry》2020,141(1):301-312
Journal of Thermal Analysis and Calorimetry - The refrigerator unit based on electrically driven vapor compression technology consumes high energy, associated with high cost and loss of ecosystem.... 相似文献
208.
Emma van Groesen Dr. Christopher T. Lohans Dr. Jürgen Brem Kristina M. J. Aertker Prof. Dr. Timothy D. W. Claridge Prof. Dr. Christopher J. Schofield 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(51):11837-11841
Bacterial production of β-lactamases with carbapenemase activity is a global health threat. The active sites of class D carbapenemases such as OXA-48, which is of major clinical importance, uniquely contain a carbamylated lysine residue which is essential for catalysis. Although there is significant interest in characterizing this post-translational modification, and it is a promising inhibition target, protein carbamylation is challenging to monitor in solution. We report the use of 19F NMR spectroscopy to monitor the carbamylation state of 19F-labelled OXA-48. This method was used to investigate the interactions of OXA-48 with clinically used serine β-lactamase inhibitors, including avibactam and vaborbactam. Crystallographic studies on 19F-labelled OXA-48 provide a structural rationale for the sensitivity of the 19F label to active site interactions. The overall results demonstrate the use of 19F NMR to monitor reversible covalent post-translational modifications. 相似文献
209.
Letters in Mathematical Physics - A recent generalization of the “Kleinian sigma function” involves the choice of a point P of a Riemann surface X, namely a “pointed curve”... 相似文献
210.
Emma R. L. Brisson James C. Griffith Ayana Bhaskaran George V. Franks Luke A. Connal 《Journal of polymer science. Part A, Polymer chemistry》2019,57(18):1964-1973
Histidine functional block copolymers are thermally self‐assembled into polymer micelles with poly‐N‐isopropylacrylamide in the core and the histidine functionality in the corona. The thermally induced self‐assemblies are reversible until treated with Cu2+ ions at 50 °C. Upon treatment with 0.5 equivalents of Cu2+ relative to the histidine moieties, metal‐ion coordination locks the self‐assemblies. The self‐assembly behavior of histidine functional block copolymers is explored at different values of pH using DLS and 1H NMR. Metal‐ion coordination locking of the histidine functional micelles is also explored at different pH values, with stable micelles forming at pH 9, observed by DLS and imaged by atomic force microscopy. The thermal self‐assembly of glycine functional block copolymers at pH 5, 7, and 9 is similar to the histidine functional materials; however, the self‐assemblies do not become stable after the addition of Cu2+, indicating that the imidazole plays a crucial role in metal‐ion coordination that locks the micelles. The reversibility of the histidine‐copper complex locking mechanism is demonstrated by the addition of acid to protonate the imidazole and destabilize the polymer self‐assemblies. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1964–1973 相似文献