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391.
Vitagliano L Vergara A Bonomi G Merlino A Verde C di Prisco G Howes BD Smulevich G Mazzarella L 《Journal of the American Chemical Society》2008,130(32):10527-10535
392.
Figuerola A Fiore A Di Corato R Falqui A Giannini C Micotti E Lascialfari A Corti M Cingolani R Pellegrino T Cozzoli PD Manna L 《Journal of the American Chemical Society》2008,130(4):1477-1487
A one-pot, two-step colloidal strategy to prepare bimagnetic hybrid nanocrystals (HNCs), comprising size-tuned fcc FePt and inverse spinel cubic iron oxide domains epitaxially arranged in a heterodimer configuration, is described. The HNCs have been synthesized in a unique surfactant environment by temperature-driven sequential reactions, involving the homogeneous nucleation of FePt seeds and the subsequent heterogeneous growth of iron oxide. This self-regulated mechanism offers high versatility in the control of the geometric features of the resulting heterostructures, circumventing the use of more elaborate seeded growth techniques. It has been found that, as a consequence of the exchange coupling between the two materials, the HNCs exhibit tunable single-phase-like magnetic behavior, distinct from that of their individual components. In addition, the potential of the heterodimers as effective contrast agents for magnetic resonance imaging techniques has been examined. 相似文献
393.
Tolga Zorlu I. Brian Becerril-Castro Dr. Begoña Puertolas Prof. Vincenzo Giannini Prof. Miguel A. Correa-Duarte Prof. Ramon A. Alvarez-Puebla 《Angewandte Chemie (International ed. in English)》2023,62(26):e202305299
Hybrid composites between nanoparticles and metal organic frameworks (MOFs) have been described as optimal materials for a wide range of applications in optical sensing, drug delivery, pollutant removal or catalysis. These materials are usually core-shell single- or multi-nanoparticles, restricting the inorganic surface available for reaction. Here, we develop a method for the preparation of yolk-shells consisting in a plasmonic gold nanostar coated with MOF. This configuration shows more colloidal stability, can sieve different molecules based on their size or charge, seems to show some interesting synergy with gold for their application in photocatalysis and present strong optical activity to be used as SERS sensors. 相似文献
394.
Marcelo F Cañada FJ André S Colombo C Doro F Gabius HJ Bernardi A Jiménez-Barbero J 《Organic & biomolecular chemistry》2012,10(30):5916-5923
Natural N-glycosylation involves a β-anomeric linkage connecting the sugar to one asparagine residue of the protein. We herein report NMR- and modelling-based data on glycomimetics containing α-glycosidic linkages. The bioactivity of α-Gal-containing glycopeptides has been documented by revealing binding to two plant lectins, i.e. a potent β-trefoil toxin (Viscum album agglutinin) and β-sandwich lectin (Erythrina corallodendron agglutinin), by NMR protocols. Docking provided insights into the 3D structures of the resulting complexes. These results provide the basis to introduce α-substituted neoglycopeptides to the toolbox of scaffold for the design of potent lectin inhibitors. 相似文献
395.
Pilolli R Ditaranto N Di Franco C Palmisano F Cioffi N 《Analytical and bioanalytical chemistry》2012,404(6-7):1703-1711
Metal nanomaterials have an emerging role in surface-assisted laser desorption ionisation-mass spectrometry (SALDI-MS) providing a useful tool to overcome some limitations intrinsically related to the use of conventional organic matrices in matrix-assisted LDI-MS. In this contribution, the possibility to use a stainless-steel-supported gold nanoparticle (AuNP) film as a versatile platform for SALDI-MS was assessed. A sacrificial anode electrosynthetic route was chosen in order to obtain morphologically controlled core-shell AuNPs; the colloidal AuNPs were, thereafter, drop cast onto a stainless-steel sample plate and the resulting AuNP film was thermally annealed in order to improve its effectiveness as LDI-MS promoter. Spectroscopic characterization of the nanostructured film by X-ray photoelectron spectroscopy was crucial for understanding how annealing induced changes in the surface chemistry and influenced the performance of AuNPs as desorption/ionisation promoter. In particular, it was demonstrated that the post-deposition treatments were essential to enhance the AuNP core/analyte interaction, thus resulting in SALDI-MS spectra of significantly improved quality. The AuNP films were applied to the detection of three different classes of low molecular weight (LMW) analytes, i.e. amino acids, peptides and LMW polymers, in order to demonstrate the versatility of this nanostructured material. 相似文献
396.
Archimede Rotondo Giovanna Loredana La Torre Teresa Gervasi Giacomo di Matteo Mattia Spano Cinzia Ingallina Andrea Salvo 《Molecules (Basel, Switzerland)》2021,26(15)
A fast HPLC method with fluorescence detector (FD) was developed for the determination of three tocopherols (TOCs) in milk samples from Modicana cattle breed. The ultrasound-assisted procedure was optimized for the extraction of TOCs prior to HPLC/FD analysis, reducing sample preparation time and allowing a fast quantification of α-tocopherol, δ-tocopherol and γ tocopherol. The optimized ultrasonic extraction combines an efficient and simple saponification at room temperature and a rapid HPLC quantification of TOCs in milk. The precision of the full analytical procedure was satisfactory and the recoveries at three spiked levels were between 95.3% and 87.8%. The linear correlations were evaluated (R2 > 0.99) and the relative standard deviation (RSD) values for intra-day and inter-day tests at three spiked levels were below 1% for the retention time and below 5.20% for the area at low level spiking. The proposed procedure, reducing the experimental complexity, allowed accurate extraction and detection of three TOCs in milk samples from Modicana cattle breed. 相似文献
397.
Bini R Chiappe C Marmugi E Pieraccini D 《Chemical communications (Cambridge, England)》2006,(8):897-899
Imidazolium ionic liquids containing [Tf2N]- anion are not as innocent as they are often considered; [Tf2N]- is more reactive than Br- in heterolytic dediazoniation reactions. 相似文献
398.
D'Anna F Frenna V Macaluso G Marullo S Morganti S Pace V Spinelli D Spisani R Tavani C 《The Journal of organic chemistry》2006,71(15):5616-5624
We have recently evidenced an interesting differential behavior in the reactivity in dioxane/water between the (Z)-2,4-dinitrophenylhydrazone (1a) and the (Z)-phenylhydrazone (1b) of 5-amino-3-benzoyl-1,2,4-oxadiazole. The former rearranges into the relevant triazole 2a only at pS+ > 4.5 while undergoing hydrolysis at high proton concentration (pS+ < 3.5); on the contrary, the latter rearranges into 2b in the whole pS+ range examined (0.1 < or = pS+ < or = 14.9). Thus, for a deeper understanding of these differences we have now collected kinetic data on the rearrangement in dioxane/water of a series of 3- or 4-substituted (Z)-phenylhydrazones (1c-l) of 5-amino-3-benzoyl-1,2,4-oxadiazole in a wide range of proton concentrations (pS+ 0.1-12.3) with the aim of gaining information about the effect of the substituent on the course of the reaction. All of the (Z)-arylhydrazones studied rearrange via three different reaction routes (specific-acid-catalyzed, uncatalyzed, and general-base-catalyzed), and the relevant results have been examined by means of free energy relationships. 相似文献
399.
The chemical synthesis and 1H NMR analysis of a novel bicyclic uridine derivative, with a 18-crown-6 ether moiety fused at the ribose 2- and 3-positions, as first example of a hitherto unknown class of ribose-modified nucleosides, are here described. NMR-based conformational analysis studies showed for the modified nucleoside a marked preference for an N-type sugar puckering and the nucleobase in the anti conformation, with the uracil favouring the coordination of a sodium ion hosted in the crown ether. 相似文献
400.
Riccardo Bini Cinzia Chiappe Veronica L. Mestre Christian S. Pomelli Thomas Welton 《Theoretical chemistry accounts》2009,123(3-4):347-352
The Diels-Alder reaction between cyclopentadiene and three dienophiles (acrolein, methyl acrylate and acrylonitrile) in different room temperature ionic liquids containing imidazolium-based cations ([HBIM]+, [BMIM]+ and [BM2IM]+) has been studied at the DFT level using a supermolecular approach. An analysis of the theoretical results shows that the ionic liquid cation coordination affects the equilibrium geometries and electronic structures of the reacting species throughout the reaction pathway leading to changes in reactivity and selectivity. They also indicate that the strong asynchronicity of the Diels-Alder reactions in ionic liquids is due to the polarisation effect of the cation. 相似文献