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1.
Kornelija Lasi Ana Bokuli Astrid Mili Biljana Nigovi Ana Mornar 《Biomedical chromatography : BMC》2019,33(8)
This paper presents lipophilicity and bio‐mimetic property determination of 15 phytoestrogens, namely biochanin A, daidzein, formononetin, genistein, genistein‐4,7‐dimethylether, prunetin, 3,4,7‐trihydroxyisoflavon, 4,6,7‐trihydroxyisoflavon, 4,6,7‐trimethoxyisoflavon, daidzin, genistin, ononin, sissotrin, coumestrol and coumestrol dimethylether. High‐performance liquid chromatography with fast gradient elution and Caco‐2 cell line were used to determine the physicochemical properties of selected phytoestrogens. Lipophilicity was determined on octadecyl‐sylane stationary phase using pH 2.0 and pH 7.4 buffers. Immobilized artificial membrane chromatography was used for prediction of interaction with biological membranes. Protein binding was measured on human serum albumin and α‐1‐acid‐glycoprotein (AGP) stationary phases. Caco‐2 assay was used as a gold standard for assessing in vitro permeability. The obtained results differentiate phytoestrogens according to their structure where aglycones show significantly higher lipophilicity, immobilized artificial membrane partitioning, AGP binding and Caco‐2 permeability compared with glucosides. However, human serum albumin binding was very high for all investigated compounds. Furthermore, a good correlation between experimentally obtained chromatographic parameters and in silico prediction was obtained for lipophilicity and human serum albumin binding, while the somewhat greater difference was obtained for AGP binding and Caco‐2 permeability. 相似文献
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Osorio Ana C. P. de Sena Rodrigo C. Araújo Thiago de O. de Almeida Marcelo D. 《Accreditation and quality assurance》2019,24(5):387-394
Accreditation and Quality Assurance - The production of Certified Reference Materials (CRMs) is one of the essential activities of the National Institute of Metrology, Quality and Technology... 相似文献
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Anaïs Coffinet Dr. David Specklin Dr. Laure Vendier Prof. Dr. Michel Etienne Dr. Antoine Simonneau 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(63):14300-14303
The first example of a formal 1,3-B−H bond addition across the M−N≡N unit of an end-on dinitrogen complex has been achieved. The use of Piers’ borane HB(C6F5)2 was essential to observe this reactivity and it plays a triple role in this transformation: 1) electrophilic N2-borylation agent, 2) Lewis acid in a frustrated Lewis pair-type B−H bond activation, and 3) hydride shuttle to the metal center. This chemistry is supported by NMR spectroscopy and solid-state characterization of products and intermediates. The combination of chelate effect and strong σ donation in the diphosphine ligand 1,2-bis(diethylphosphino)ethane was mandatory to avoid phosphine dissociation that otherwise led to complexes where borylation of N2 occurred without hydride transfer. 相似文献
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Ana Diniz Dr. Helena Coelho Dr. Jorge S. Dias Dr. Sandra J. van Vliet Prof. Dr. Jesús Jiménez-Barbero Prof. Dr. Francisco Corzana Prof. Dr. Eurico J. Cabrita Dr. Filipa Marcelo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(61):13945-13955
The human macrophage galactose-type lectin (MGL), expressed on macrophages and dendritic cells (DCs), modulates distinct immune cell responses by recognizing N-acetylgalactosamine (GalNAc) containing structures present on pathogens, self-glycoproteins, and tumor cells. Herein, NMR spectroscopy and molecular dynamics (MD) simulations were used to investigate the structural preferences of MGL against different GalNAc-containing structures derived from the blood group A antigen, the Forssman antigen, and the GM2 glycolipid. NMR spectroscopic analysis of the MGL carbohydrate recognition domain (MGL-CRD, C181-H316) in the absence and presence of methyl α-GalNAc (α-MeGalNAc), a simple monosaccharide, shows that the MGL-CRD is highly dynamic and its structure is strongly altered upon ligand binding. This plasticity of the MGL-CRD structure explains the ability of MGL to accommodate different GalNAc-containing molecules. However, key differences are observed in the recognition process depending on whether the GalNAc is part of the blood group A antigen, the Forssman antigen, or GM2-derived structures. These results are in accordance with molecular dynamics simulations that suggest the existence of a distinct MGL binding mechanism depending on the context of GalNAc moiety presentation. These results afford new perspectives for the rational design of GalNAc modifications that fine tune MGL immune responses in distinct biological contexts, especially in malignancy. 相似文献
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From superhydrophobic‐ to superhydrophilic‐patterned poly(vinylidene fluoride‐co‐chlorotrifluoroethylene) architectures as a novel platform for biotechnological applications 下载免费PDF全文
Vanessa F. Cardoso Ana R. Machado Vânia C. Pinto Paulo J. Sousa Gabriela Botelho Graça Minas Senentxu Lanceros‐Méndez 《Journal of Polymer Science.Polymer Physics》2016,54(18):1802-1810
The manufacture of three‐dimensional patterned electroactive poly(vinylidene fluoride‐co‐chlorotrifluoroethylene) microstructures with tailored architecture, morphology, and wettability is presented. The patterned microstructures are fabricated using a simple, effective, low cost, and reproducible technique based on microfluidic technology. These novel structures can represent innovative platforms for advanced strategies in a wide range of biotechnological applications, including tissue engineering, drug delivery, microfluidic, and sensors and actuators devices. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 1802–1810 相似文献
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The First One‐Pot Synthesis of Metal–Organic Frameworks Functionalised with Two Transition‐Metal Complexes 下载免费PDF全文
Dr. Ana E. Platero‐Prats Dr. Antonio Bermejo Gómez Dr. Louise Samain Prof. Xiaodong Zou Prof. Belén Martín‐Matute 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(2):861-866
The synthesis of a metal–organic framework (UiO‐67) functionalised simultaneously with two different transition metal complexes (Ir and Pd or Rh) through a one‐pot procedure is reported for the first time. This has been achieved by an iterative modification of the synthesis parameters combined with characterisation of the resulting materials using different techniques, including X‐ray absorption spectroscopy (XAS). The method also allows the first synthesis of UiO‐67 with a very wide range of loadings (from 4 to 43 mol %) of an iridium complex ([IrCp*(bpydc)(Cl)Cl]2?; bpydc=2,2′‐bipyridine‐5,5′‐dicarboxylate, Cp*=pentamethylcyclopentadienyl) through a pre‐functionalisation methodology. 相似文献
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