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171.
Charlotte A. Henshaw Adam A. Dundas Valentina Cuzzucoli Crucitti Morgan R. Alexander Ricky Wildman Felicity R. A. J. Rose Derek J. Irvine Philip M. Williams 《Molecules (Basel, Switzerland)》2021,26(11)
Droplet microfluidics can produce highly tailored microparticles whilst retaining monodispersity. However, these systems often require lengthy optimisation, commonly based on a trial-and-error approach, particularly when using bio-instructive, polymeric surfactants. Here, micropipette manipulation methods were used to optimise the concentration of bespoke polymeric surfactants to produce biodegradable (poly(d,l-lactic acid) (PDLLA)) microparticles with unique, bio-instructive surface chemistries. The effect of these three-dimensional surfactants on the interfacial tension of the system was analysed. It was determined that to provide adequate stabilisation, a low level (0.1% (w/v)) of poly(vinyl acetate-co-alcohol) (PVA) was required. Optimisation of the PVA concentration was informed by micropipette manipulation. As a result, successful, monodisperse particles were produced that maintained the desired bio-instructive surface chemistry. 相似文献
172.
Paul A. Maggard Amy L. Kopf Charlotte L. Stern Kenneth R. Poeppelmeier 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(4):m207-m209
The title compound, [Cu(Cr2O7)(C10H8N2)2], a new mixed‐metal molecular compound, contains isolated molecular units, each comprised of one CuII atom coordinated to two 2,2′‐bipyridine ligands and also to an oxygen vertex of a dichromate anion. The CuII atom has an approximate trigonal–bipyramidal geometry, which is consistent with previous studies. Both enantiomers of the chiral complex molecule are present and are related by inversion centers. In a reported pyridine analogue, achiral [Cu(Cr2O7)(pyridine)4] chains pack in the non‐centrosymmetric space group Pna21. Differences in the organic ligands influence the chirality and dimensionality of the Cu—Cr2O7 bonding. 相似文献
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175.
Rastogi SC Zachariae C Johansen JD Devantier C Menné T 《Journal of chromatography. A》2004,1031(1-2):315-317
An increased frequency of contact allergy to methyldibromoglutaronitrile (MDBGN), a commonly used preservative in cosmetics and other consumer products, has been reported in recent years. A high-performance liquid chromatography (HPLC) method for the determination of MDBGN in cosmetic products has been validated in the present study. The identification is performed by reductive electrochemical detection of the bromine present in the molecule. The method is suitable for compliance testing of cosmetic products as well as for the research to support clinical and epidemiological studies. 相似文献
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177.
Gustavo R. Plaza Paola Corsini Enrico Marsano José Pérez‐Rigueiro Manuel Elices Christian Riekel Charlotte Vendrely Gustavo V. Guinea 《Journal of Polymer Science.Polymer Physics》2012,50(7):455-465
Regenerated silkworm fibers spun through a wet‐spinning process followed by an immersion postspinning drawing step show a work to fracture comparable with that of natural silkworm silk fibers in a wide range of spinning conditions. The mechanical behavior and microstructure of these high performance fibers have been characterized, and compared with those fibers produced through conventional spinning conditions. The comparison reveals that both sets of fibers share a common semicrystalline microstructure, but significant differences are apparent in the amorphous region. Besides, high performance fibers show a ground state and the possibility of tuning their tensile behavior. These properties are characteristic of spider silk and not of natural silkworm silk, despite both regenerated and natural silkworm silk share a common composition different from that of spider silk. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献
178.
Iresha D. Herath Dr. Colum Breen Dr. Sarah H. Hewitt Dr. Thomas R. Berki Dr. Ahmad F. Kassir Dr. Charlotte Dodson Martyna Judd Dr. Shereen Jabar Dr. Nicholas Cox Prof. Gottfried Otting Dr. Stephen J. Butler 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(51):13009-13023
A lanthanide-binding tag site-specifically attached to a protein presents a tool to probe the protein by multiple spectroscopic techniques, including nuclear magnetic resonance, electron paramagnetic resonance and time-resolved luminescence spectroscopy. Here a new stable chiral LnIII tag, referred to as C12 , is presented for spontaneous and quantitative reaction with a cysteine residue to generate a stable thioether bond. The synthetic protocol of the tag is relatively straightforward, and the tag is stable for storage and shipping. It displays greatly enhanced reactivity towards selenocysteine, opening a route towards selective tagging of selenocysteine in proteins containing cysteine residues. Loaded with TbIII or TmIII ions, the C12 tag readily generates pseudocontact shifts (PCS) in protein NMR spectra. It produces a relatively rigid tether between lanthanide and protein, which is beneficial for interpretation of the PCSs by single magnetic susceptibility anisotropy tensors, and it is suitable for measuring distance distributions in double electron–electron resonance experiments. Upon reaction with cysteine or other thiol compounds, the TbIII complex exhibits a 100-fold enhancement in luminescence quantum yield, affording a highly sensitive turn-on luminescence probe for time-resolved FRET assays and enzyme reaction monitoring. 相似文献
179.
Stepan Shipovskov Karsten M. Kragh Brian S. Laursen Charlotte H. Poulsen Flemming Besenbacher Duncan S. Sutherland 《Applied biochemistry and biotechnology》2010,160(4):1124-1129
The formation of noncovalent complexes between glycosidase, endo-1,4-β-d-mannanase, and ionic surfactant di(2-ethylhexyl) sodium sulfosuccinate (AOT) was shown to promote protein transfer into organic
solvents such as xylene and hexane. It was found that mannanase can be solubilized in hexane and in xylene with concentration
at least 2.5 and 2.0 mg/ml, respectively. The catalytic activity of the enzyme in hexane spontaneously increases with the
concentration of AOT and is about 10% of the activity in aqueous system. In xylene, a catalytic activity higher than that
in bulk aqueous conditions was found for the samples containing 0.1–0.3 mg/ml of mannanase, while for the samples with a higher
concentration of enzyme, the activity was hardly detected. 相似文献
180.
Charlotte Fairbanks 《Fresenius' Journal of Analytical Chemistry》1899,38(2):113-114
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