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51.
F Ortega-Caballero J J Giménez-Martínez L García-Fuentes E Ortiz-Salmerón F Santoyo-González A Vargas-Berenguel 《The Journal of organic chemistry》2001,66(23):7786-7795
The inclusion behavior and concanavalin A binding properties of hepta-antennated and newly synthesized tetradeca-antennated C-6-branched mannopyranosyl and glucopyrannosyl cyclomaltoheptaose (beta-cyclodextrin) derivatives have been evaluated by isothermal titration microcalorimetry and enzyme-linked lectin assay (ELLA), respectively. The synthesis of three first-order dendrimers based on a beta-cyclodextrin core containing 14 1-thio-beta-D-glucose, 1-thio-beta-mannose, and 1-thio-beta-rhamnose residues was performed following a convergent approach and involving (1) preparation of a thiolated bis-branched glycoside building block and (2) attachment of the building block onto heptakis(6-deoxy-6-iodo)-beta-cyclodextrin. Calorimetric titrations performed at 25 degrees C in buffered aqueous solution (pH 7.4) gave the affinity constants and the thermodynamic parameters for the inclusion complex formation of these beta-cyclodextrin derivatives with guests sodium 8-anilino-1-naphthalensulfonate (ANS) and 2-naphthalenesulfonate. The host capability of the persubstituted beta-cyclodextrins decreased with respect to the native beta-CD when sodium 2-naphthalenesulfonate was used as a guest and improved when ANS was used as a guest molecule. Heptavalent mannoclusters based on beta-CD cores enhance the lectin binding affinity due to the cluster effect; however, the increase of the valency from 7 to 14 ligands did not contribute to the improvement of the concanavalin A binding affinity. In addition, the synthesized hyperbranched mannoCDs lost completely the capability as a host molecules. 相似文献
52.
Lluís Cabedo José Luis Feijoo María Pilar Villanueva José María Lagarón Enrique Giménez 《Macromolecular Symposia》2006,233(1):191-197
Biodegradable blends of amorphous poly(lactic acid) (aPLA) and polycaprolactone (PCL) and nanocomposites of these blends were developed by melt blending. A morphological study of the bioblends was carried out by means of WAXS and SEM showing immiscible behavior. The nanocomposites were also characterized morphologically by WAXS, TEM and SEM, revealing high degree of interaction of the nanoclays with the aPLA. Mechanical, thermal and gas barrier properties of the different blends and nanocomposites were studied and the effect of blending and clay addition on the above-mentioned properties was evaluated. 相似文献
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José A. Jimena García José Giménez Plaza José M. Cano Pavón 《Fresenius' Journal of Analytical Chemistry》1994,349(7):542-545
Two procedures for the determination of active components in insecticide formulations have been devised. The first is based in the use of derivative spectra of the components obtained by a diode-array spectrophotomer around the maxima signal of the chromatographic peak. In the second method, mixtures are resolved by the partial least-squares (PLS) regression method from standard spectra of the pure components; spectra of the components were also registered around the maxima signal of the peak. Both procedures have been applied to the analysis of diverse mixtures of active components (piperonyl butoxide, neopynamine and fenitrothion) in insecticide formulations with satisfactory results. 相似文献
56.
Blay G Fernández I Giménez T Pedro JR Ruiz R Pardo E Lloret F Muñoz MC 《Chemical communications (Cambridge, England)》2001,(20):2102-2103
A new manganese(II) oxamato dimer possesing an unprecedented Mn2(mu-O2CR)(mu-OH2...O2CR) core has been synthesised, structurally and magnetically characterised, and used as a catalyst for the oxidation of alkanes to alcohols and ketones by ButO2H and O2 in CH2Cl2 at rt. 相似文献
57.
Águeda Sonseca Sandra Camarero‐Espinosa Laura Peponi Christoph Weder E. Johan Foster José M. Kenny Enrique Giménez 《Journal of polymer science. Part A, Polymer chemistry》2014,52(21):3123-3133
Polyesters based on polyols and sebacic acid, known as poly(polyol sebacate)s (PPS), are attracting considerable attention, as their properties are potentially useful in the context of soft‐tissue engineering applications. To overcome the drawback that PPSs generally display rather low strength and stiffness, we have pursued the preparation of nanocomposites based poly(mannitol sebacate) (PMS), a prominent example of this materials family, with cellulose nanocrystals (CNCs). Nanocomposites were achieved in a two‐step process. A soluble, low‐molecular‐weight PMS pre‐polymer was formed via the polycondensation reaction between sebacic acid and D‐mannitol. Nanocomposites with different CNC content were prepared by solution‐casting and curing under vacuum using two different profiles designed to prepare materials with low and high degree of crosslinking. The as‐prepared nanocomposites have higher stiffness and toughness than the neat PMS matrix while maintaining a high elongation at break. A highly crosslinked nanocomposite with a CNC content of 5 wt % displays a sixfold increase in Young's modulus and a fivefold improvement in toughness. Nanocomposites also exhibit a shape memory effect with a switch temperature in the range of 15 to 45 °C; in particular the materials with a thermal transition in the upper part of this range are potentially useful for biomedical applications. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 3123–3133 相似文献
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59.
Quan Chen Jason Gim Hong Tan Shou Cang Shen Yu Chan Liu Wai Kiong Ng Xian Ting Zeng 《Journal of Sol-Gel Science and Technology》2007,44(2):125-131
AlOOH boehmite nanorods, synthesized by a solid-based process, were incorporated into a sol–gel coating in which GPTS was
used as a precursor. Transparent composite coatings with nanorod content up to 40 wt% were obtained by spin coating the sol–gel
mixture on glass substrates. Nanorods in the coating were found be aligned parallel to the substrate surface. Mechanical properties,
such as modulus and hardness of the nanorod filled coating, were slightly lower than coatings of the same composition but
filled with commercially available nanosized boehmite particles. However, crack toughness was greatly improved, as supported
by nanoindentation test results. The improvement in crack toughness was attributed to the high aspect ratio of the rigid nanorods,
in addition to the fact that the nanorods were aligned within the composite parallel to the surface. 相似文献
60.
Estela Giménez Fernando Benavente José Barbosa Victoria Sanz-Nebot 《Analytical and bioanalytical chemistry》2010,398(1):357-365
2,5-Dihydroxybenzoic acid (DHB) has been demonstrated to be a more suitable matrix than 3,5-dimethoxy-4-hydroxycinnamic acid
(sinapinic acid, SA) to obtain reliable molecular mass values of intact glycoproteins because it prevents sugar fragmentation.
Lack of spot homogeneity during the crystallization step was prevented by drying the sample-matrix mixture under vacuum conditions.
Nevertheless, this sample-matrix preparation procedure requires a specific experimental setup and may be time-consuming. In
this work, we investigated the effectiveness of different ionic liquid matrices (ILMs) with SA and DHB on the ionization of
a set of intact glycoproteins with several degrees of glycosylation. The obtained results demonstrate that some of the tested
ILMs allow detection of the studied intact glycoproteins. Furthermore, the selected optimum conditions solve the reproducibility
issue of using the DHB as a solid matrix without the vacuum drying method and, surprisingly, avoid sugar fragmentation when
both SA and DHB were used as ILMs. 相似文献