Centro Of Studi E Ricerche Enrico Fermi

Rome, Italy

Centro Of Studi E Ricerche Enrico Fermi

Rome, Italy
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Minati L.,CNR Institute of Biophysics | Chiappini A.,CNR Institute for Photonics and Nanotechnologies | Armellini C.,CNR Institute for Photonics and Nanotechnologies | Carpentiero A.,CNR Institute for Photonics and Nanotechnologies | And 10 more authors.
Materials Chemistry and Physics | Year: 2017

A new strategy to produce easily scalable patterned array of gold nanoparticles on flexible substrate is presented. Aligned gold nanoparticles 1D arrays deposited on polydimethylsiloxane (PDMS) were produced by a combination of water-in-oil self-assembling and lift-off microprinting technique. Morphological and optical properties of the obtained structures were investigated by AFM, absorption and reflectance spectroscopy. The optical response of the structured elastomer in respect to uniaxial deformation was measured in order to assess its suitability as strain sensor. © 2017 Elsevier B.V.


Berneschi S.,CNR Institute of Applied Physics Nello Carrara | Baldini F.,CNR Institute of Applied Physics Nello Carrara | Cosci A.,CNR Institute of Applied Physics Nello Carrara | Cosci A.,Centro Of Studi E Ricerche Enrico Fermi | And 9 more authors.
Sensors and Actuators, B: Chemical | Year: 2017

A procedure for a spatially selective immobilization of antibodies, via photochemical activation, on the inner surface of optical microbubble resonators (OMBRs) is reported. The method is based on a suitable UV mask process. As proof of concept of this technique, immunoassay in photo-activated OMBR was implemented and fluorescence investigation was conducted. Moreover, the possible application of this procedure towards the development of a biochemical multiplexed detection system based on OMBR is presented. Finally, the high Q factor values measured after the immunoassay event (>105) make these photo–activated OMBRs suitable devices for future label-free biosensor implementation. © 2016 Elsevier B.V.


Chiasera A.,CNR Institute for Photonics and Nanotechnologies | Criante L.,Italian Institute of Technology | Varas S.,CNR Institute for Photonics and Nanotechnologies | Della Valle G.,CNR Institute for Photonics and Nanotechnologies | And 10 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2017

We present the possibility to tailor the optical properties of 1D photonic structures by using more than two materials and by clustering the high refractive index (hRI) layer in the structures. In particular, we show that: i) with a photonic crystal made of i different materials, the photonic band gap splits in i-1 bands; ii) with a proper choice of the layer thickness, disordered photonic structures made with a high number of layers show periodic transmission peaks; iii) when the size of the hRI layer clusters, randomly distributed within the low refractive index layers, follows a power law distribution, the total light transmission follows a sigmoidal function. Furthermore, we discuss the fabrication aspects to realize the above mentioned photonic structures. © 2017 SPIE.


Lukowiak A.,CNR Institute for Photonics and Nanotechnologies | Lukowiak A.,Institute of Low Temperature And Structure Research | Wiglusz R.J.,Institute of Low Temperature And Structure Research | Chiappini A.,CNR Institute for Photonics and Nanotechnologies | And 6 more authors.
Journal of Non-Crystalline Solids | Year: 2014

Nanoparticles of lithium lanthanum tetraphosphates doped with different concentration of Eu3 + ions were synthesized. The selected tetraphosphate was used to fabricate a transparent composite where nanocrystals were immobilized in a sol-gel-derived silica-hafnia amorphous film. The structural and spectroscopic properties of the systems were investigated by XRD analysis, Raman spectroscopy, and photoluminescence measurements. For all the samples with the Eu3 + ions concentration from 1 to 100 mol% the monoclinic structure with a space group C12/c1 was determined. The mean diameter of nanocrystals determined by Scherrer equation was in the range of 40-55 nm. The luminescence of 10%Eu3 +:LiLa(PO3)4 in silica-hafnia matrix indicated the immobilization of Eu3 + ions into a distorted environment. The dependence of both luminescence intensity and lifetime on the Eu3 + concentration demonstrated effective reduction of concentration quenching in the tetraphosphate nanopowders. © 2013 Elsevier B.V.


Lukowiak A.,Institute of Low Temperature And Structure Research | Marciniak L.,Institute of Low Temperature And Structure Research | Vasilchenko I.,CNR Institute for Photonics and Nanotechnologies | Vasilchenko I.,University of Trento | And 7 more authors.
International Conference on Transparent Optical Networks | Year: 2016

A group of nanocrystalline polyphosphates is presented showing the advantages arising from their spectroscopic properties. Their unique optical features are related, among others, with their structural properties. For example, reduced cross relaxation processes between doped lanthanide ions are observed in tetraphosphate matrices due to the relatively large active ions distance. For selected praseodymium doped polyphosphates, such as LiPr(PO3)4, a cascade emission transitions can be observed due to the two-step 4f2 transitions that take place under UV excitation into 4f5d levels. Such property could be used for scintillation devices. Other interesting behavior is the efficient anti-Stokes white broadband emission induced by NIR laser diode in LiYb(PO3)4 nanocrystals. Additionally, the properties of planar waveguides based on SiO2-HfO2 system and doped with P2O5 or tetraphosphate nanocrystals are presented. © 2016 IEEE.


Zmojda J.,University of Bialystok | Kochanowicz M.,University of Bialystok | Miluski P.,University of Bialystok | Lukowiak A.,Institute of Low Temperature And Structure Research | And 9 more authors.
International Conference on Transparent Optical Networks | Year: 2016

In this article we present possibility of obtaining nano-phase structures in glasses and optical fibers doped with RE ions. Effect of phosphate on structural and optical properties of antimony-germanate glasses doped with Eu3+ions have been investigated. Modification of Sb2O3 - GeO2 - SiO2 - Al2O3 - Na2O glass system by P2O5 (up to 10 mol.%) shows possibility of creation of the EuPO4 phosphate nanophase. Controlled heat-treatment process selected glasses are used as a core of optical fiber. The luminescence spectra of glass, glass-ceramics and optical fibers were compared and discussed in terms of embedding nano-crystalline phase structures in RE - doped optical fiber. © 2016 IEEE.


Berneschi S.,Centro Of Studi E Ricerche Enrico Fermi | Berneschi S.,CNR Institute of Neuroscience | Chiappini A.,CNR Institute for Photonics and Nanotechnologies | Ferrari M.,CNR Institute for Photonics and Nanotechnologies | And 2 more authors.
Physica Status Solidi (C) Current Topics in Solid State Physics | Year: 2011

Aim of this paper is to present a short review of the main results obtained in our laboratories on Er3+-doped SiO2: HfO2 glass ceramic waveguides fabricated by sol-gel route and dip-coating technique, employing either top-down or bottom-up approach. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Dinuzzo M.,Centro Of Studi E Ricerche Enrico Fermi | Giove F.,Centro Of Studi E Ricerche Enrico Fermi | Giove F.,University of Rome La Sapienza | Maraviglia B.,Centro Of Studi E Ricerche Enrico Fermi | And 2 more authors.
Journal of Neurochemistry | Year: 2013

The non-metabolizable fluorescent glucose analogue 6-(N-(7-nitrobenz-2-oxa- 1,3-diazol-4-yl)amino)-2-deoxyglucose (6-NBDG) is increasingly used to study cellular transport of glucose. Intracellular accumulation of exogenously applied 6-NBDG is assumed to reflect concurrent gradient-driven glucose uptake by glucose transporters (GLUTs). Here, theoretical considerations are provided that put this assumption into question. In particular, depending on the microscopic parameters of the carrier proteins, theory proves that changes in glucose transport can be accompanied by opposite changes in flow of 6-NBDG. Simulations were carried out applying the symmetric four-state carrier model on the GLUT1 isoform, which is the only isoform whose kinetic parameters are presently available. Results show that cellular 6-NBDG uptake decreases with increasing rate of glucose utilization under core-model conditions, supported by literature, namely where the transporter is assumed to work in regime of slow reorientation of the free-carrier compared with the ligand-carrier complex. To observe an increase of 6-NBDG uptake with increasing rate of glucose utilization, and thus interpret 6-NBDG increase as surrogate of glucose uptake, the transporter must be assumed to operate in regime of slow ligand-carrier binding, a condition that is currently not supported by literature. Our findings suggest that the interpretation of data obtained with NBDG derivatives is presently ambiguous and should be cautious because the underlying transport kinetics are not adequately established. In this study, we used the four-state carrier model for brain GLUT1 to examine whether cellular glucose metabolism can be inferred from the accumulation of the fluorescent glucose analogue 6-NBDG, which is increasingly employed for indirect determination of glucose transport and utilization in neurons and astrocytes. However, our findings show that the relation between 6-NBDG uptake and glucose transport and utilization configures antiport not symport of the two substrates. © 2013 International Society for Neurochemistry.


Berneschi S.,Centro Of Studi E Ricerche Enrico Fermi | Berneschi S.,CNR Institute of Neuroscience | Brenci M.,CNR Institute of Neuroscience | Nunzi Conti G.,CNR Institute of Neuroscience | And 11 more authors.
Optical Engineering | Year: 2011

Slab optical waveguides were fabricated in tung-sten-tellurite glass doped with Er3 ions by means of nitrogen ion implantation at 1.5 MeV. A wide range of ion doses (from 51012 to 8.1016 ionscm 2) was used. Optical characterization, performed by dark-line spectroscopy, revealed that the waveguides were of optical barrier type: the implanted layer exhibited a decrease of the refractive index with respect to the virgin bulk glass, while the region comprised between the sample surface and the end of the ion track acted as an optical guiding structure. It was also demonstrated that a post-implantation annealing process, performed at various temperatures on the samples implanted at higher doses, contributes to the reduction of the barrier region. © 2011 Society of Photo-Optical Instrumentation Engineers (SPIE).

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