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Seven new bio-inspired chemosensors (2-4 and 7-10) based on fluorescent peptides were synthesized and characterized by elemental analysis, 1H-NMR, 13C-NMR, melting point, matrix assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF-MS), infrared, UV-vis absorption and emission spectroscopy. The interaction with transition and post-transition metal ions (Cu2+, Ni2+, Ag+, Zn2+, Cd2+, Hg2+, Pb2+ and Fe3+) has been explored by absorption and fluorescence emission spectroscopy and MALDI-TOF mass spectrometry. The reported fluorescent peptide systems, introducing biological molecules in the skeleton of the probes, enhance their sensitivity and confer them strong potentials for applications in biological fields. Gold and silica nanoparticles functionalized with these peptides were also obtained. All nanoparticles were characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), UV-vis absorption and fluorescence spectroscopy. Stable gold nanoparticles (diameter 2-10 nm) bearing ligands 1 and 4 were obtained by common reductive synthesis. Commercial silica nanoparticles were decorated at their surface using compounds 8 to 10, linked through a silane spacer. The same chemosensors were also taken into aqueous solutions through their dispersion in the outer layer of silica core/PEG shell nanoparticles. In both cases, these complex nanoarchitectures behaved as new sensitive materials for Ag+ and Hg2+ in water. The possibility to use these species in this solvent is particularly valuable since the impact on human health of heavy and transition metal ions pollution is very severe, and all analytical and diagnostics investigations involve a water environment., Fundação para a Ciência e a Tecnologia (FCT), Universidade do Minho (UM)

The field of nanoparticles is amazingly many-sided and consequently their applications range between many different areas from industry to bio-analysis and catalysis. In particular, luminescent nanoparticles attract close attention in the areas of biology, medical diagnosis and therapy, where they already find many applications. In this so fascinating and wide framework we have focussed our attention on luminescent silica nanoparticles able to act as sensing materials. We highlight here the importance, especially with the aim of sensing, of gaining precise knowledge and control of their structures; the performance of a chemosensor is, in fact, totally dependent on its design. We then briefly present the state of the art and the progress both in the synthetic protocols and in the application of luminescent silica nanoparticles as chemosensors. We present many recent examples, organized into two main sections, the first dealing with systems presenting the signalling units on the surface (dye coated silica nanoparticles, DCSNs) and the second with systems entrapping the dyes inside the silica matrix (dye doped silica nanoparticles, DDSNs).

Nanoparticelle di silice drogate con una molteplicità di coloranti caratterizzate da trasferimento di energia ad elevata efficienza e capaci di Stokes Shift modulabile.

In accordance with a first aspect of the present invention, it is provided a method for the preparation of an active nanoparticle, comprising a mixing step, during which at least one active compound is mixed with molecules of at least one surfactant in an organic solvent; an evaporation step, that is subsequent to the mixing step and during which the organic solvent is evaporated in order to obtain a residue; a reaction step, which is subsequent to the evaporation step and during which molecules of at least one alkoxysilane are added to the residue and silanized in presence of water; the alkoxysilane is chosen between a tetraalkoxysilane and a trialkoxysilane; the surfactant comprising the following structure: Hydro1-Lipo-Hydro2 wherein Lipo indicates a substantially hydrophobic chain, Hydro1 and Hydro2 each indicate a substantially hydrophilic chain. Advantageously, the active compound is substantially lipophilic.

The present invention relates to methods for the preparation of an active particle, active particles and uses of these active particles. The purpose of this invention is to provide active particles, uses of particles and methods for the preparation of particles, which allow overcoming, at least partially, the drawbacks of the state of the art and are, at the same time, easy and economical to implement. According to the present invention the following are provided: active particles, uses of particles and methods for the preparation of particles as specified in the independent claims which follow and, preferably, in any of the claims directly or indirectly dependent on the independent claims.

Nanoparticelle luminescenti e/o elettroattive e/o adatte ad applicazioni di MRI (magnetic resonance imaging) e/o ad applicazioni di PET (positron emission tomography) vengono preparate facendo idrolizzare-condensare tetraalcossisilani assieme a composti luminescenti od elettroattivi, i quali possono contenere funzionalità alcossisilaniche, in una soluzione acquosa in presenza di copolimeri a blocco (block-copolymers) etilene ossido/propilene ossido; le nanoparticelle ottenute mostrano un nullo o trascurabile rilascio dei composti luminescenti od elettroattivi e sono utili per applicazioni bio-analitiche e biomediche.