Glycosphingolipid clustering and interactions at the cell membrane can be modeled by gold glyconanoparticles prepared with biologically significant oligosaccharides. Such water‐soluble gold glyconanoparticles with highly polyvalent carbohydrate displays (see picture, gray hemisphere: gold nanoparticle) have been obtained by a simple and versatile strategy.

CommuniCation(1 of 7) 1601087 synthesis of PbI 2 nanocrystals and their subsequent reaction with CH 3 NH 3 I 3 to produce the corresponding organic-inorganic lead halide quantum dots. [4] More recently, powders of porous silica exhibiting a 2D hexagonal mesopore structure have been used as templates to synthesize MAPbI 3 nanocrystals. [14,15] This approach proved to be suitable to attain bright and stable emission whose spectrum could be controlled by the average pore size of the matrix. However, most applications foreseen for hybrid perovskites require the use of thin films of high optical quality, as well as versatility regarding the composition of the scaffold employed. In order to achieve this goal, mesostructures with geometries other than the hexagonal one previously employed to host perovskite nanocrystals must be used, since the characteristic tubular channels tend to lie parallel to the substrate when the porous material is shaped as a film, becoming inaccessible from the top surface. This prevents their infiltration with perovskite precursors. Very recently, MAPbI 2 X (X = Cl, Br, I) compounds have been synthesized inside metal organic framework films, [16] but no control over the size and optical properties of MAPbI 3 was demonstrated.In this Communication, we demonstrate a synthetic route to obtain stabilized MAPbI 3 nanocrystals embedded in thin metal oxide films that display well-defined and adjustable quantum confinement effects over a wide range of 0.34 eV. Mesostructured TiO 2 and SiO 2 films displaying an ordered 3D pore network are prepared by evaporation induced self-assembly of a series of organic supramolecular templates in the presence of metal oxide precursors. The pores in the inorganic films obtained after thermal annealing are then used as nanoreactors to synthesize MAPbI 3 crystallites with narrow size distribution and average radius comprised between 1 and 4 nm, depending on the template of choice. Both the static and dynamic photoemission properties of the ensemble display features distinctive of the regime of strong quantum confinement. Photoemission maps demonstrate that the spectral and intensity properties of the luminescence extracted from the perovskite quantum dot loaded films are homogeneous over squared centimeters areas. In addition, the photoemission stationary state is reached 10 4 times faster than in a MAPbI 3 solid film. One of the most versatile strategies to tune the optical properties of a semiconductor consists in reducing its size until it becomes of the order of the exciton Bohr radius and quantum confinement effects arise. [1] Different methods have been developed to try to controllably diminish the size of methyl ammonium lead halide (MAPbX 3 , X = Cl, Pb, I) crystals, [2][3][4][5][6][7] motivated by the interest these perovskites generate in the field of optoelectronics. [8][9][10][11][12] Efforts in obtaining dispersions of hybrid organic-inorganic perovskite nanocrystals for optoelectronic applications have mainly focused on MAPbBr 3 and MAPbBr x I 3-x , a...

Ein Modellsystem für die Clusterbildung von Glycosphingolipiden und ihre Wechselwirkung mit Zellmembranen sind Gold‐Glyco‐Nanopartikel, die mit biologisch relevanten Oligosacchariden hergestellt wurden. Diese wasserlöslichen Nanopartikel mit hochfunktionalisierten Kohlenhydratoberflächen (die graue Halbkugel im Bild ist das Gold‐Nanopartikel) konnten mittels einer einfachen und universellen Strategie erhalten werden.

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In this work, we demonstrate a synthetic route to attain methylammonium lead bromide (CH3NH3PbBr3) perovskite nanocrystals (nc-MAPbBr3, 1.5 nm

Lead halide perovskite nanocrystals have demonstrated their potential as active materials for optoelectronic applications over the past few years. Nevertheless, one issue that hampers their applicability has to do with the observation of photoluminescence intermittency, commonly referred to as “blinking”, as in their inorganic counterparts. Such behavior, reported for structures well above the quantum confinement regime, has been discussed to be strongly related to the presence of charge carrier traps. In this work, we analyze the characteristics of this intermittency and explore the dependence on the surrounding atmosphere, showing evidence for the critical role played by the presence of oxygen. We discuss a possible mechanism in which a constant creation/annihilation of halide-related carrier traps takes place under light irradiation, with the dominant rate being determined by the atmosphere.

Clinical contrast agents (CAs) currently used in magnetic resonance imaging (MRI) at low fields are less effective at high magnetic fields. The development of new CAs is mandatory to improve diagnostic capabilities of the new generation of high field MRI scanners. The purpose of this study is to synthesize uniform, water dispersible LnF3 (Ln = Ho, Dy) nanoparticles (NPs) and to evaluate their relaxivity at high magnetic field (9.4 T) as a function of size and composition. Two different types of HoF3 NPs are obtained by homogeneous precipitation in ethylene glycol at 120 °C. The use of holmium acetate as holmium precursor leads to rhombus‐like nanoparticles, while smaller, ellipsoid‐like nanoparticles are obtained when nitrate is used as the holmium salt. To explain this behavior, the mechanism of formation of both kinds of particles is analyzed in detail. Likewise, rhombus‐like DyF3 nanoparticles are prepared following the same method as for the rhombus‐like HoF3 nanoparticles. We have found, to the best of knowledge, the highest transverse relaxivity values at 9.4 T described in the literature for this kind of CAs. Finally, the LnF3 NPs have shown negligible cytotoxicity for C6 rat glioma cells for concentrations up to 0.1 mg mL−1.

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