Triazine-Carbon Nanotubes: New Platforms for the Design of Flavin Receptors.

The synthesis of functionalised carbon nanotubes as receptors for riboflavin (RBF) is reported. Carbon nanotubes, both single-walled and multi-walled, have been functionalised with 1,3,5-triazines and p-tolyl chains by aryl radical addition under microwave irradiation and the derivatives have been fully characterised by using a range of techniques. The interactions between riboflavin and the hybrids were analysed by using fluorescence and UV/Vis spectroscopic techniques.

Carboxylated, Fe-filled multiwalled carbon nanotubes as versatile catalysts for O2 reduction and H2 evolution reactions at physiological pH.

The development of new electrocatalysts for the oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) at physiological pH is critical for several fields, including fuel cells and biological applications. Herein, the assembly of an electrode based on carboxyl-functionalised hydrophilic multiwalled carbon nanotubes (MWCNTs) filled with Fe phases and their excellent performance as electrocatalysts for ORR and HER at physiological pH are reported. The encapsulated Fe dramatically enhances the catalytic activity, and the graphitic shells play a double role of efficiently mediating the electron transfer to O2 and H2 O reactants and providing a cocoon that prevents uncontrolled Fe oxidation or leaching.

Chemical characterization of Titan's tholins: solubility, morphology and molecular structure revisited.

In this work Titan's atmospheric chemistry is simulated using a capacitively coupled plasma radio frequency discharge in a N(2)-CH(4) stationnary flux. Samples of Titan's tholins are produced in gaseous mixtures containing either 2 or 10% methane before the plasma discharge, covering the methane concentration range measured in Titan's atmosphere. We study their solubility and associated morphology, their infrared spectroscopy signature and the mass distribution of the soluble fraction by mass spectrometry.

SR4987 and L1210 cell lines: two models in which cholera toxin susceptibility does not correlate with cAMP accumulation and ganglioside content.

The CT-mediated signaling mechanisms have been widely used as a tool for helping the knowledge of the more complex mechanisms regulating cell growth and proliferation in which gangliosides are involved as receptors and cAMP as second messenger. In the present study we compare the susceptibility of two murine cell lines (SR-4987 stromal cells and L1210 leukemic cells) to inhibitory effect of cholera toxin (CT) on cell growth and correlate their sensitivity to CT with ganglioside content and intracellular cAMP accumulation. The results indicate a very different response of the two cell lines to CT treatment.