0000000000819903
AUTHOR
Julien Boudon
Phthalocyanine–titanate nanotubes: a promising nanocarrier detectable by optical imaging in the so-called imaging window
International audience; TiONts-phthalocyanine nanohybrids combining an efficient optical probe and a promising nanovector have been developed in a step-by-step approach and were thoroughly characterized. Each 150 nm long TiONts-Pc bear ca. 450 Pc. Three nanohybrids were prepared including three different linkers in quest for the best stability.
Magneto-optical nanomaterials: a SPIO–phthalocyanine scaffold built step-by-step towards bimodal imaging
A SPIO-phthalocyanine nanohybrid is developed as a bimodal contrast agent for Optical and Magnetic Resonance Imaging. The organic coating was covalently attached onto SPIO in a step-by-step approach. Each coated-SPIO was thoroughly characterized. The hydrodynamic size of the SPIO-Pc is ca. 60 nm with a coverage of ca. 690 Pc/SPIO.
Size Exclusion Chromatography for Semipreparative Scale Separation of Au 38 (SR) 24 and Au 40 (SR) 24 and Larger Clusters
Size exclusion chromatography (SEC) on a semipreparative scale (10 mg and more) was used to size-select ultrasmall gold nanoclusters (2 nm) from polydisperse mixtures. In particular, the ubiquitous byproducts of the etching process toward Au(38)(SR)(24) (SR, thiolate) clusters were separated and gained in high monodispersity (based on mass spectrometry). The isolated fractions were characterized by UV-vis spectroscopy, MALDI mass spectrometry, HPLC, and electron microscopy. Most notably, the separation of Au(38)(SR)(24) and Au(40)(SR)(24) clusters is demonstrated.
The first catalytic method for Heck alkynylation of unactivated aryl bromides (copper-free Sonogashira) in an ionic liquid: 1 mol-percent palladium/triphenylphosphane/pyrrolidine in [BMIM][BF4] as a simple, inexpensive and recyclable system
Herein we report the studies of Heck alkynylation (copper-free Sonogashira) with aryl halides (I, Br, Cl) employing various metallic precursors, tertiary phosphanes and bases in [BMIM][BF4] as the solvent. As a result, we provide the first method that allows the coupling of a large array of substrates, either activated or deactivated bromides in an ionic liquid. Furthermore, the system of highest efficiency is unexpectedly the simplest and cheaper combination that employs [Pd(η3-C3H5)Cl]2/PPh3 at only a 1 mol-% loading with pyrrolidine as the base and in the absence of a copper salt. The coupling of sterically and electronically deactivated bromides bearing different functional groups to ar…
In vitro hazard assessment of nanoparticles developed for biomedical applications
Nanotechnology is a growing sector in industry for twenty years and nanomaterials are currently used in numerous industrials applications. Their interest is based on their dimensions and their shape that give them very particular technological and biological properties. However, the development of these nanoparticles, their industrial preparation and integration into various products already involve an initial increased of human exposure (via inhalation, percutaneous and oral route). Another exposure pathway exists and is represented by drug injections. The risks associated with these new technologies and new products are still unclear. After a characterization step (zeta potential, TEM, TG…
Alumina particle reinforced TiO2 composite films grown by direct liquid injection MOCVD
Abstract The use of a liquid injection delivery system to form composite films containing nanoparticles was investigated. Al 2 O 3 –TiO 2 films were grown on silicon substrates by direct liquid injection MOCVD (DLI-MOCVD) at 400 °C. The α-Al 2 O 3 nanoparticles (α-Al 2 O 3 NPs) dispersed in TiO 2 films resulted from co-deposition using colloidal α-Al 2 O 3 solution and titanium tetraisopropoxide as titanium precursor. Scanning electron microscopy coupled with EDS as well as Raman spectroscopy confirmed the presence of α-Al 2 O 3 NPs aggregates embedded in the TiO 2 matrix. The liquid injection system coupled with CVD technique can be promising to form composite films containing preformed na…
DNA structure-specific sensitization of a metalloporphyrin leads to an efficient in vitro quadruplex detection molecular tool
International audience; The search for convenient molecular probes for detecting DNA and RNA quadruplexes in vitro is marked by a rapid pace of progress, spurred on by the multiple roles these higher-order nucleic acid structures play in many genetic dysregulations. Here, we contribute to this search, reporting on a palladated porphyrin named Pd.TEGPy: its efficiency as quadruplex-selective fluorescent dye relies on a structural design that endows it with attractive supramolecular and electronic properties and makes it an efficient turn-on, quadruplex-selective fluorescent stain thanks to a DNA-mediated sensitization mechanism that ensures a high level of specificity.
Dispersion of titanate nanotubes for nanomedicine: comparison of PEI and PEG nanohybrids.
In the present study, we report the dispersion of titanate nanotubes (TiONts) via polymer grafting (PolyEthylene Glycol, PEG) or polymer adsorption (polyethylene imine, PEI) where different TiONts/polymer ratios have been investigated. The TiONts/PEI and TiONts/PEG nanohybrids were characterized by scanning and transmission electron microscopy as well as by zeta potential measurements in order to determine both their dispersion state and stability in water (at different pH for zetametry). The nature of the chemical bonds at the surface of these nanohybrids was investigated by Fourier-transformed infrared (FTIR) spectroscopy while the grafting densities of PEG on the nanotubes were quantifie…
{1,1′-Bis[bis(5-methyl-2-furyl)phosphino]ferrocene-κ2P,P′}dichloroplatinum(II) dichloromethane hemisolvate
The synthesis of the title compound, [FePtCl2(C15H14O2P)2]·0.5CH2Cl2, has been achieved by reacting PtCl2(PhCN)2 with the 1,1′-bis[bis(5-methyl-2-furyl)phosphino]ferrocene chelating ligand. The environment at the Pt atom can be described as distorted square-planar, with two cis-Cl atoms and two cis-P atoms.
Elaboration of Trans-Resveratrol Derivative-Loaded Superparamagnetic Iron Oxide Nanoparticles for Glioma Treatment
In this work, new nanohybrids based on superparamagnetic iron oxide nanoparticles (SPIONs) were elaborated and discussed for the first time as nanovectors of a derivative molecule of trans-resveratrol (RSV), a natural antioxidant molecule, which can be useful for brain disease treatment. The derivative molecule was chemically synthesized (4&rsquo
Thermal stability of Au–TiO2 nanocomposite films prepared by direct liquid injection CVD
Abstract Nanocomposite films composed of gold nanoparticles (AuNPs) embedded in a TiO 2 matrix have been prepared by direct liquid injection chemical vapor deposition process, using preformed nanoparticles and titanium isopropoxide as precursors. The spherical AuNPs about 4.1 nm in diameter were synthesized by using gold (III) chloride trihydrate and stabilized by thiol ligands. The depositions were carried out by performing at first oxide deposition, then gold nanoparticle one and capping with oxide. The morphology, structure; the chemical state and optical properties of nanocomposite films were characterized by scanning electron microscopy, Raman, X-ray photoelectron and UV–Vis absorption…