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Superparamagnetic iron oxide nanoparticles (SPIONs) have received increasing interest as contrast media in biomedical imaging and innovative therapeutic tools, in particular for loco-regional ablative treatments and drug delivery. The future of therapeutic applications would strongly benefit from improving the capability of the nanostructured constructs to reach the selected target, in particular beyond the intravascular space. Besides the decoration of SPIONs surface with ad hoc bioactive molecules, external magnetic fields are in principle able to remotely influence SPIONs' physiological biodistribution and concentrate them to a specific anatomical region or portion of a tissue. The reduction of SPIONs administered to the body and the need for defining the effective SPIONs local concentration suggest that PET/CT may be a method to quantitatively detect the nanoparticles accumulation in vivo at low concentration and assess their tridimensional distribution in response to an external magnetic field and in relation to the local anatomy highlighted by CT imaging. Here, we report on the possibility to assess the spatial distribution of magnetically-driven radiolabelled SPIONs in a peripheral tissue (mouse thigh) with microPET/CT imaging. To this aim we labelled SPIONs using 18 F-2-fluoro-2-deoxyglucose as a synthon, by chemoselective oxime formation between its open-chain tautomer and nanoparticle amino-groups, and employed microPET/CT imaging to measure the radiolabelled construct biodistribution in a small animal model, following intravenous administration, with and without the application of a permanent magnet onto the skin. The in vivo and ex vivo results showed that micro-PET/CT was able to demonstrate the localizing action of the magnet on SPIONs and provide information, in a multimodal 3D data set, about SPIONs biodistribution taking into account the local anatomy. Copyright © 2017 John Wiley & Sons, Ltd., (Copyright © 2017 John Wiley & Sons, Ltd.)

ABSTRACT Homogeneous core-shell systems were obtained with a growth, in controlled steps, of several oligoamides on TiO2 nanoparticles. Derivatives of natural compounds, such as l-tartaric acid and α,α′-trehalose, were used as diesters in the polycondensation reactions with ethylenediamine. TiO2 anatase was chosen because of its high photo-activity and its antimicrobial activity. The TiO2 nanoparticles had been previously activated then functionalized using two different coupling agents, and finally, the TiO2-oligoamide nanocomposites were synthesized using two synthetic pathways. The final products were characterized by 1H NMR, 13C NMR, FT-IR, and transmission electron microscope. These nanocomposites can show improved properties in comparison with the single components (TiO2 nanoparticles or oligoamides), which are useful in many fields, such as antimicrobial coatings for surfaces in cultural heritage conservation. A nanocomposite (TiO2-polyethylenetartaramide) was used for applicative studies, and it has shown a good efficacy against fungal attack by Trametes versicolor on wood specimens ( Fagus sylvatica). © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42047. [ABSTRACT FROM AUTHOR]

Cucurbita pepo L. presents a nonedible biomass potentially valuable for the synthesis of gold nanoparticles (AuNPs). Searching environmental conditions which can affect AuNPs' yield and structure, extracts were obtained from plants treated with excess metal ions in the culture medium. AuNPs one-pot synthesis was conducted at 40°C for 30 min with diluted HAuCl4. Shoot extracts yielded a high number of spherical nanoparticles with lower size than AuNPs obtained from root extracts. Interestingly, root extracts from plants grown in the presence of Cu(II), Ag(I), or Au(III) gave nanoparticles with treatment-dependent shape, whereas using shoot extracts this phenomenon was not observed. This result could be attributed to metal-imposed specific changes in the cell antioxidant pool. Total polyphenol concentration in the extracts was correlated with the differences obtained in nanoparticle production. Atomic clusters from the metal accumulated in the plant, acting as specific nucleation seeds, could contribute to the synthesis of differently shaped nanoparticles. [ABSTRACT FROM AUTHOR]

Highlights: [•] Hybrid zirconia/polyvinyl alcohol catalytic membrane containing Pd nanoparticles. [•] Partial hydrogenation reactions in the liquid phase of multiple C C and C C bonds. [•] Efficient under mild reaction conditions. [•] No metal leaching, reusable, stable, use of hydrophilic solvents, no need of regeneration. [Copyright &y& Elsevier]