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Replacing fossil-C based plastics with those derived from renewable-C is one of the goals of the modern polymer industry. 2,5-Furan dicarboxylic acid (2,5-FDCA) is a candidate to substitute terephthalic acid as comonomer for polyesters. 2,5-FDCA is usually produced from C6 sugars. Carboxylation of 2-furancarboxylic acid (2-FCA) to 2,5-FDCA is an alternative synthetic approach to such monomer for polyethene furoate (PEF) preparation. In this work, several inorganic carbonates have been tested in the 2-FCA carboxylation in presence and absence of CO2. A key copper intermediate has been synthesized and fully characterized that is able to increase the acidity and, thus, the reactivity of 5-H towards a carbonate species. Carboxylation occurs at 93% yield in absence of CO2. The role of metal salts and CO2 were investigated. The conversion yield of 2-FCA into the dicarboxylic acid is related to the charge density on the metal cation, increasing with lower charge-density.

A characterization of solid lipid nanoparticles (SLN) produced starting from an emulsion prepared in acidic or neutral medium and based on Gelucire® 50/13 as lipid phase was performed by X-Ray Photoelectron Spectroscopy Analysis (XPS). The smallest particle size and the highest peptide content were observed for GSH-SLN produced in acidic medium [GSH-SLN(HAc)]. XPS analysis demonstrate the absence of GSH from the surface of the SLN and, combined with the observed sustained release kinetics, allowed us to propose the peptide GSH localization within the lipid nanoparticles. Differential Scanning Calorimetry thermograms of the GSH loaded SLN revealed the absence of the melting point peak at 193 °C attributable to the peptide, suggesting the decreased crystallinity of GSH in the lipid Gelucire® 50/13 forming the SLN matrix. SAF-1 cells (fibroblast-like cells derived from the fin) and gilthead seabream leukocytes were incubated in the presence of FITC-SLN. However, confocal microscopy confirmed that both types of cells were unable to internalize SLN. This result may be ascribed to the slightly negative surface-charge of labelled particles which is unfavorable for effective interactions of these essentially neutral particles with fish cells, suggesting, in perspective, the need to modify the carrier system surface in order to target cell fish.

The Pt(IV) prodrug of kiteplatin, cis-trans-cis-[PtCl2(RS-Ibuprofen-H)2(cis-1,4-DACH)], having in the axial positions two molecules of Ibuprofen, has been synthesised, characterized and tested in vitro. The aim was to potentiate the cytotoxic effect of kiteplatin with the anti-inflammatory activity of Ibuprofen. The reduction potential of the conjugate resulted comparable to those of other reported Pt(IV) carboxylate complexes, ensuring in vivo stability in blood during transport and intracellular reduction with release of the active species. The cytotoxic activity of the complex resulted remarkably potentiated reaching nanomolar activity. It is possible that the coordinated Ibuprofen molecules promote the transport and the accumulation of the complex in tumor cells by increasing its lipophilicity. In addition to the increased uptake, Ibuprofen could also exert an anti-inflammatory action mediated by inhibition of the COX enzymes which are overexpressed in tumors. The use of a conjugate with Pt-bound Ibuprofen can ensure similar cellular uptake and biodistribution for both the anti-inflammatory and the cytotoxic drugs in the exact ratio of 2:1.

Gold (Au) nanoparticles stabilized on metal oxide supports offer superior catalytic activity and recyclability in organic catalysis. We report for the first time synthesis of indium oxide stabilized gold (Au@In2O3) nanocatalysts using an electrochemical procedure and their application in homocoupling of arylboronic acids. In2O3 nanoparticles prepared via sol-gel process are subjected to sacrificial anode electrolysis (SAE) under inert condition for electrodeposition of nano Au on In2O3. Thus Au@In2O3 nanoparticles obtained are thermally annealed at high temperature to partially oxidize Au and to remove any surfactants. XPS results show the existence of both elemental (nano Au) and cationic (Au3+) species in Au@In2O3 nanocatalysts, while SEM images confirm the presence of nanoscale Au (< 10 nm) particles on In2O3 surface. Au@In2O3 nanocatalysts are tested for arylboronic acids homocoupling under different conditions and it is found that they are highly active in organic medium with K2CO3 base and demonstrate excellent conversion (> 97%) and selectivity (> 98%). The catalyst recyclability and performance towards differently substituted arylboronic acids is also studied and a plausible mechanism of action is proposed. (C) 2014 Elsevier B.V. All rights reserved.

The present work is aimed at developing gold nanostructures functionalized with antenna systems to exploit the synergistic nanostructure/antenna desorption-ionization efficiency. A potential Matrix-Assisted Laser Desorption Ionisation (MALDI) organic matrix has been modified introducing specific functional groups or molecular linker and used as a capping agent for gold nanostructures. In particular, conjugated naphthyl-thio-derivative, i.e. 4-mercaptonaphthalene-1,8-dicarboxylic acid, was synthesized and characterized by means of nuclear magnetic resonance, UV–visible and X-ray photoelectron spectroscopies. Afterwards, the thio-derivative was used as covalent surface modifier for flat gold surfaces and nanostructured gold films. These surfaces were thoroughly characterized by means of parallel angle-resolved X-ray photoelectron spectroscopy to obtain quantitative information about elemental composition, chemical speciation, and in-depth distribution of the target chemical functional groups. Finally the compound was preliminarily tested as a non-conventional matrix in Laser Desorption Ionisation Mass Spectrometry (LDI-MS) analysis of low molecular weight biomolecules in order to assess its capability of acting as the antenna system and proton donor after covalent bonding to gold nanomaterials.

In this paper a study of Multi Wall Carbon Nanotube films deposited at low temperature by means of a spray technique on different substrates is presented. Nanodispersion of nanotube powder in a non-polar 1,2-dichloroethane solvent was used as starting solution. Electron Microscopy in Scanning and Transmission modes were used in order to verify the morphological properties of the deposited films. Visible light detectors were prepared spraying Multi Wall Carbon Nanotubes on silicon substrates with different layouts. In some detectors the nanotubes were covered by an Indium Tin Oxide (ITO) layer. Electrical measurements, both in dark and under light irradiation, were performed and Current-Voltage characteristics are reported. The Indium Tin Oxide coating effect on the photoconductivity yield is presented and discussed along with device ageing test, resulting in a very good photoconduction and stability over four months.

In the present study, gold/surfactant core/shell colloidal nanoparticles with a controlled morphology and chemical composition have been obtained via the so-called sacrificial anode technique, carried out in galvanostatic mode. As synthesized Au-NPs had an average core diameter comprised between 4 and 8 nm, as a function of the electrochemical process experimental conditions. The UV-Vis characterization of gold nanocolloids showed clear spectroscopic size effects, affecting both the position and width of the nanoparticle surface plasmon resonance peak. The nanomaterial surface spectroscopic characterization showed the presence of two chemical states, namely nanostructured Au(0) (its abundance being higher than 90%) and Au(I). Au-NPs were then deposited on the top of a capacitive field effect sensor and subjected to a mild thermal annealing aiming at removing the excess of stabilizing surfactant molecules. Au-NP sensors were tested towards some gases found in automotive gas exhausts. The sensing device showed the largest response towards NOx, and much smaller - if any - responses towards interferent species such as NH3, H-2, CO, and hydrocarbons. Original Publication: Nicola Cioffi, Lorenzo Colaianni, Eliana Ieva, Rosa Pilolli, Nicoletta Ditaranto, Maria Daniela Angione, Serafina Cotrone, Kristina Buchholt, Anita Lloyd Spetz, Luigia Sabbatini and Luisa Torsi, Electrosynthesis and characterization of gold nanoparticles for electronic capacitance sensing of pollutants, 2011, ELECTROCHIMICA ACTA, (56), 10, 3713-3720. http://dx.doi.org/10.1016/j.electacta.2010.12.105 Copyright: Elsevier Science B.V., Amsterdam. http://www.elsevier.com/

"A multi-step plasma procedure for the fabrication of high-quality SiO2/Si interfaces and the functionalization of silicon dioxide surfaces has been developed for microelectronic manufacturing industry. The substrate activation based on a plasma-enhanced chemical vapour deposition (PECVD) has been developed in order to obtain high quality SiO2/Si heterostructures. The SiO2 films have been then exposed to additional PECVD processes in order to modify the dielectric surface by polar groups. The advantage of this method consists in the possibility of activating the substrate, depositing and functionalizing high-quality SiO2 films in a single run process, at low temperature, and by means of the same equipment. The reported method has also been exploited to produce device-quality silicon nitride/silicon heterostructures; preliminary results are shown. (C) 2007 Elsevier B.V. All rights reserved."

A two-step bottom up preparation protocol is proposed as a useful tool for the controlled modification of tin oxide films by means of Pd nanoparticles (PdNPs). Colloidal palladium is prepared via an electrolytic process that affords for a core-shell particle structure, while nanostructured tin oxide films are prepared following a sol-gel process. Pd/SnO"x composite layers are obtained adding a proper aliquot of pre-formed PdNPs to the tin oxide precursor solution. The nanomaterials surface chemical composition is addressed by X-ray Photoelectron Spectroscopy. Preliminary results on the application of Pd/SnO"x as active layers in chemiresistor-type gas-sensing devices are reported, as well.

Catalysts made of Pd supported on ZrO2 were prepared via a sacrificial anode electrosynthesis route. Tetragonal zirconia was added to an electrolytic cell assembled for the preparation of colloidal Pd nanoparticles. Several samples were prepared varying the electrolysis time and thus the Pd loading in the nanocomposite. XRD analysis showed the presence of the tetragonal ZrO2 mainly and some small reflections due to monoclinic ZrO2. BET surface areas were in the range 70–80 m2 g−1. The morphology and surface chemical composition of the nano-materials were, respectively, assessed by transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) analyses. From TEM evidence, the Pd-ZrO2 powders revealed to be composed of spherical Pd nanoparticles (average core diameter: 6.9 ± 1.8 nm) evenly dispersed on the surface of ZrO2 nano-grains (average grain size: 150 ± 70 nm, average size of crystallites composing each grain: 40 ± 10 nm). XPS allowed to quantify the surface elemental composition of the nanomaterials and to study the different chemical states of the nano-dispersed palladium. Catalysts were tested for CH4 total combustion and for CO oxidation. The conversion increased with Pd content in the CH4 combustion experiments whereas decreased with Pd content in the CO oxidation experiments. The apparent activation energies were about 25 and 9 kcal mol−1 for CH4 combustion and CO oxidation, respectively. Hypothesis was made that different reaction mechanisms and different active sites were probably involved in the two reactions.

Palladium–fluoropolymer nanostructured composites (Pd–CFx) are deposited by a separate and simultaneous sputtering of bulk Teflon and palladium targets in a vacuum chamber. Such nano-material can find application as active layer in sensing devices, as it swells when exposed to the vapors of organic solvents such as acetone, chloroform, 2-propanol. Ellipsometry shows that the swelling extent linearly depends on the solvent partial pressure in the measuring chamber. Moreover, Pd–CFx sensitivity and selectivity features are different to those of a parent gold–fluoropolymer (Au–CFx) nanocomposite, investigated in previous studies. In particular, Pd–CFx layers are generally more sensitive than Au–CFx ones, particularly in the case of chlorinated solvents, which are scarcely detectable by Au–CFx nanocomposites. The material morphological and chemical structure has been investigated by means of atomic force and transmission electron microscopies along with X-ray photoelectron (XPS) and Fourier transform infra-red spectroscopies. The analytical characterization demonstrates that morphological similarities exist between Pd–CFx films and Au–CFx ones having the same metal volume fraction ϕ. XPS also reveals an almost identical surface structure for the dispersing polymer matrix of homologous Pd–CFx and Au–CFx films. Metal fluorides and oxides are identified as well and differences in the materials sensing performances are then ascribed to the presence of different amounts of these species that also have a different chemical reactivity and selectivity.