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2014
Bianchi, A, Delgado-Pinar E, Garcia-Espana E, Giorgi C, Pina F.  2014.  Highlights of metal ion-based photochemical switches. Coordination Chemistry Reviews. 260:156-215. AbstractWebsite
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Bianchi, A, Delgado-Pinar E, Garcia-Espana E, Giorgi C, Pina F.  2014.  Highlights of metal ion-based photochemical switches. Coordination Chemistry Reviews. 260:156-215. AbstractWebsite
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Sa, S, Gawande MB, Velhinho A, Veiga JP, Bundaleski N, Trigueiro J, Tolstogouzov A, Teodoro OMND, Zboril R, Varma RS, Branco PS.  2014.  Magnetically recyclable magnetite-palladium (Nanocat-Fe-Pd) nanocatalyst for the Buchwald-Hartwig reaction. GREEN CHEMISTRY. 16:3494-3500., Number 7 Abstract
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Pessoa, JC, Gonçalves G, Roy S, Correia I, Mehtab S, Santos MFA, Santos-Silva T.  2014.  New insights on vanadium binding to human serum transferrin. Inorganica Chimica Acta. 420:60-68. AbstractWebsite

Abstract The knowledge on the binding of vanadium ions and complexes to serum proteins and how vanadium might be transported in blood and up-taken by cells has received much attention during the last decade, particularly as far as the transport of VIVO2+ is concerned. In this work we revise and discuss some relevant aspects of previous research, namely the two main types of binding proposed for transport of VIVO(carrier)2 complexes. New results, obtained by circular dichroism (CD), \{EPR\} and gel electrophoresis, regarding the binding of vanadium to hTF in the oxidation states +5 and +3 are also presented. Namely, evidences for the binding of VV-species to diferric-transferrin, designated by (FeIII)2hTF, as well as to (AlIII)2hTF, are presented and discussed, the possibility of up-take of vanadate by cells through (FeIII)2hTF endocytosis being suggested. It is also confirmed that \{VIII\} binds strongly to hTF, forming di-vanadium(III)-transferrin, designated by (VIII)2hTF, and gel electrophoresis experiments indicate that (VIII)2hTF corresponds to a ‘closed conformation’ similar to (FeIII)2hTF.

Nogueira, LS, Ribeiro S, Granadeiro CM, Pereira E, Feio G, Cunha-Silva L, Balula SS.  2014.  Novel polyoxometalate silica nano-sized spheres: efficient catalysts for olefin oxidation and the deep desulfurization process. Dalton Trans. 43:9518-28., Number 25 AbstractWebsite

A novel method to prepare silica nano-sized particles incorporating polyoxometalates was developed leading to a new efficient heterogeneous oxidative catalyst. Zinc-substituted polyoxotungstate [PW11Zn(H2O)O39](5-) (PW11Zn) was encapsulated into silica nanoparticles using a cross-linked organic-inorganic core, performed through successive spontaneous reactions in water. The potassium salt of PW11Zn and the composite formed, PW11Zn-APTES@SiO2, were characterized by a myriad of solid-state methods such as FT-IR, FT-Raman, (31)P and (13)C CP/MAS solid-state NMR, elemental analysis and SEM-EDS, confirming the integrity of the PW11Zn structure immobilized in the silica nanoparticles. The new composite has shown to be a versatile catalyst for the oxidation of olefins and also to catalyze the desulfurization of a model oil using H2O2 as the oxidant and acetonitrile as the solvent. The novel composite material was capable of being recycled without significant loss of activity and maintaining its structural stability for consecutive desulfurization and olefin oxidative cycles.

Bao, C, Conde J, Polo E, {del Pino} P, Moros M, Baptista P, Grazu V, Cui D, {de la Fuente} {JM }.  2014.  A promising road with challenges: where are gold nanoparticles in translational research? Nanomedicine. 9:2353–2370., Number 15: Future Medicine Ltd. Abstract

Nanoenabled technology holds great potential for health issues and biological research. Among the numerous inorganic nanoparticles that are available today, gold nanoparticles are fully developed as therapeutic and diagnostic agents both in vitro and in vivo due to their physicochemical properties. Owing to this, substantial work has been conducted in terms of developing biosensors for noninvasive and targeted tumor diagnosis and treatment. Some studies have even expanded into clinical trials. This article focuses on the fundamentals and synthesis of gold nanoparticles, as well as the latest, most promising applications in cancer research, such as molecular diagnostics, immunosensors, surface-enhanced Raman spectroscopy and bioimaging. Challenges to their further translational development are also discussed.

Gago, S, Gonzalez J, Blasco S, Parola JA, Albelda MT, Garcia-Espana E, Pina F.  2014.  Protonation, coordination chemistry, cyanometallate "supercomplex" formation and fluorescence chemosensing properties of a bis(2,2 '-bipyridino)cyclophane receptor. Dalton Transactions. 43:2437-2447., Number 6 AbstractWebsite
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Conde, J, Dias {JT }, Grazu V, Moros M, Baptista P, {de la Fuente} {JM }.  2014.  Revisiting 30 years of biofunctionalization and surface chemistry of inorganic nanoparticles for nanomedicine. Frontiers in Chemistry. 2: Frontiers Media Abstract

In the last 30 years we have assisted to a massive advance of nanomaterials in material science. Nanomaterials and structures, in addition to their small size, have properties that differ from those of larger bulk materials, making them ideal for a host of novel applications. The spread of nanotechnology in the last years has been due to the improvement of synthesis and characterization methods on the nanoscale, a field rich in new physical phenomena and synthetic opportunities. In fact, the development of functional nanoparticles has progressed exponentially over the past two decades. This work aims to extensively review 30 years of different strategies of surface modification and functionalization of noble metal (gold) nanoparticles, magnetic nanocrystals and semiconductor nanoparticles, such as quantum dots. The aim of this review is not only to provide in-depth insights into the different biofunctionalization and characterization methods, but also to give an overview of possibilities and limitations of the available nanoparticles.

Santos, MFA, Correia I, Oliveira AR, Garribba E, Pessoa JC, Santos-Silva T.  2014.  Vanadium Complexes as Prospective Therapeutics: Structural Characterization of a VIV Lysozyme Adduct. European Journal of Inorganic Chemistry. :n/a–n/a.: WILEY-VCH Verlag AbstractWebsite

The biological activity of vanadium complexes, namely, as insulin enhancers, is well known. We report a combined X-ray crystallography, electron paramagnetic resonance, and density functional theory study of the interaction of vanadium picolinate complexes with hen egg white lysozyme (HEWL). We show that the VIVO(pic)2 complex covalently binds to the COO– group of the side chain of Asp52 of HEWL. The long VIV=O bond obtained in the X-ray study is explained to be due to reduction of VIV to VIII during exposure of the crystals to the intense X-ray beam.

Costa, MN, Veigas B, Jacob JM, Santos DS, Gomes J, Baptista PV, Martins R, Inácio J, Fortunato E.  2014.  {A low cost, safe, disposable, rapid and self-sustainable paper-based platform for diagnostic testing: lab-on-paper.}. Nanotechnology. 25:094006., Number 9 AbstractWebsite

There is a strong interest in the use of biopolymers in the electronic and biomedical industries, mainly towards low-cost applications. The possibility of developing entirely new kinds of products based on cellulose is of current interest, in order to enhance and to add new functionalities to conventional paper-based products. We present our results towards the development of paper-based microfluidics for molecular diagnostic testing. Paper properties were evaluated and compared to nitrocellulose, the most commonly used material in lateral flow and other rapid tests. Focusing on the use of paper as a substrate for microfluidic applications, through an eco-friendly wax-printing technology, we present three main and distinct colorimetric approaches: (i) enzymatic reactions (glucose detection); (ii) immunoassays (antibodies anti-Leishmania detection); (iii) nucleic acid sequence identification (Mycobacterium tuberculosis complex detection). Colorimetric glucose quantification was achieved through enzymatic reactions performed within specific zones of the paper-based device. The colouration achieved increased with growing glucose concentration and was highly homogeneous, covering all the surface of the paper reaction zones in a 3D sensor format. These devices showed a major advantage when compared to the 2D lateral flow glucose sensors, where some carryover of the coloured products usually occurs. The detection of anti-Leishmania antibodies in canine sera was conceptually achieved using a paper-based 96-well enzyme-linked immunosorbent assay format. However, optimization is still needed for this test, regarding the efficiency of the immobilization of antigens on the cellulose fibres. The detection of Mycobacterium tuberculosis nucleic acids integrated with a non-cross-linking gold nanoprobe detection scheme was also achieved in a wax-printed 384-well paper-based microplate, by the hybridization with a species-specific probe. The obtained results with the above-mentioned proof-of-concept sensors are thus promising towards the future development of simple and cost-effective paper-based diagnostic devices.

Zanarini, S, Garino N, Nair JR, Francia C, Wojcik PJ, Pereira L, Fortunato E, Martins R, Bodoardo S, Penazzi N.  2014.  {Contrast Enhancement in Polymeric Electrochromic Devices Encompassing Room Temperature Ionic Liquids}. International Journal of Electrochemical Science. 9:1650–1662., Number 4 Abstract
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Pereira, S, Gonçalves A, Correia N, Pinto J, Pereira LÍ, Martins R, Fortunato E.  2014.  {Electrochromic behavior of NiO thin films deposited by e-beam evaporation at room temperature}. Solar Energy Materials and Solar Cells. 120, Part:109–115. AbstractWebsite

In this work we report the role of thickness on electrochromic behavior of nickel oxide (NiO) films deposited by e-beam evaporation at room temperature on ITO-coated glass. The structure and morphology of films with thicknesses between 100 and 500 nm were analyzed and then correlated with electrochemical response and transmittance modulation when immersed in 0.5 M LiClO4–PC electrolyte. The NiO exhibits an anodic coloration, reaching for the thickest film a transmittance modulation of 66{%} between colored and bleached state, at 630 nm, with a color efficiency of 55 cm2 C−1. Very fast switch between states was obtained, where coloration and bleaching times are 3.6 s cm−2 and 1.4 s cm−2, respectively.

Zubizarreta, C, Berasategui EG, Bayon R, Galindo ER, Barros R, Gaspar D, Nunes D, Calmeiro T, Martins R, Fortunato E, Barriga J.  2014.  {Evaluation of the optoelectronic properties and corrosion behavior of Al2O3-doped ZnO films prepared by dc pulsed magnetron sputtering}. JOURNAL OF PHYSICS D-APPLIED PHYSICS. 47, Number 48 Abstract
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Gaspar, D, Fernandes SN, de Oliveira AG, Fernandes JG, Grey P, Pontes RV, Pereira L, Martins R, Godinho MH, Fortunato E.  2014.  {Nanocrystalline cellulose applied simultaneously as the gate dielectric and the substrate in flexible field effect transistors}. Nanotechnology. 25:94008., Number 9 AbstractWebsite

Cotton-based nanocrystalline cellulose (NCC), also known as nanopaper, one of the major sources of renewable materials, is a promising substrate and component for producing low cost fully recyclable flexible paper electronic devices and systems due to its properties (lightweight, stiffness, non-toxicity, transparency, low thermal expansion, gas impermeability and improved mechanical properties). Here, we have demonstrated for the first time a thin transparent nanopaper-based field effect transistor (FET) where NCC is simultaneously used as the substrate and as the gate dielectric layer in an ‘interstrate' structure, since the device is built on both sides of the NCC films; while the active channel layer is based on oxide amorphous semiconductors, the gate electrode is based on a transparent conductive oxide. Such hybrid FETs present excellent operating characteristics such as high channel saturation mobility ({\textgreater}7 cm 2 V −1 s −1 ), drain–source current on/off modulation ratio higher than 10 5 , enhancement n-type operation and subthreshold gate voltage swing of 2.11 V/decade. The NCC film FET characteristics have been measured in air ambient conditions and present good stability, after two weeks of being processed, without any type of encapsulation or passivation layer. The results obtained are comparable to ones produced for conventional cellulose paper, marking this out as a promising approach for attaining high-performance disposable electronics such as paper displays, smart labels, smart packaging, RFID (radio-frequency identification) and point-of-care systems for self-analysis in bioscience applications, among others.

Pereira, L, Gaspar D, Guerin D, a Delattre, Fortunato E, Martins R.  2014.  {The influence of fibril composition and dimension on the performance of paper gated oxide transistors}. Nanotechnology. 25:94007., Number 9 AbstractWebsite

Paper electronics is a topic of great interest due the possibility of having low-cost, disposable and recyclable electronic devices. The final goal is to make paper itself an active part of such devices. In this work we present new approaches in the selection of tailored paper, aiming to use it simultaneously as substrate and dielectric in oxide based paper field effect transistors (FETs). From the work performed, it was observed that the gate leakage current in paper FETs can be reduced using a dense microfiber/nanofiber cellulose paper as the dielectric. Also, the stability of these devices against changes in relative humidity is improved. On other hand, if the pH of the microfiber/nanofiber cellulose pulp is modified by the addition of HCl, the saturation mobility of the devices increases up to 16 cm 2 V −1 s −1 , with an I ON / I OFF ratio close to 10 5 .

2013
Amaro, P, Schlesser S, Guerra M, Le Bigot E, Santos JP, Szabo CI, Gumberidze A, Indelicato P.  2013.  Absolute measurements and simulations of x-ray line energies of highly charged ions with a double-crystal spectrometer, Sep 23. Physica Scripta. T156:014104. AbstractWebsite
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Szabo, CI, Amaro P, Guerra M, Santos JP, Gumberidze A, Attard J, Indelicato P.  2013.  Ion temperature and x-ray line width measurements of highly charged argon ions in an ECR ion source, Sep 23. Physica Scripta. T156:014077. AbstractWebsite
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Cordeiro, M, Giestas L, Lima {JC }, Baptista P.  2013.  Coupling an universal primer to SBE combined spectral codification strategy for single nucleotide polymorphism analysis, oct. Journal of Biotechnology. 168:90–94., Number 1: Elsevier Abstract

We previously reported a strategy that combines Forster resonance energy transfer (FRET) based spectral codification with a single base extension (SBE) reaction for single nucleotide sequence discrimination in solution. This strategy is capable of unequivocally detect the allele variants present in solution. To extend the use of this tool to any locus of interest, it would be required the development of an universal approach capable of combining a sequence specific SBE primer to an universal sequence labeled and optimized for spectral codification.Here, we extend this concept to a general strategy by means of a labeled universal oligonucleotide primer (donor), a sequence specific primer that allows for incorporation of the complementary acceptor labeled ddNTP, which allows discrimination the allele variant in the sample via the unambiguous FRET signature of the donor/acceptor pair

Guerra, M, Pinto RM, Santos JP, Paiva ACS.  2013.  Towards the assignment of the REMPI spectrum of Ph 2O using CIS and TD-DFT methods, May 09. Molecular Physics. 111:3311-3319., Number 21 AbstractWebsite
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Silva, R, Folgosa F, Soares P, Pereira AS, Garcia R, Gestal-Otero JJ, Tavares P, Gomes da Silva MDR.  2013.  Occupational cosmic radiation exposure in Portuguese airline pilots: study of a possible correlation with oxidative biological markers., Jun. Radiation and environmental biophysics. 52:211-220., Number 2 AbstractWebsite

Several studies have sought to understand the health effects of occupational exposure to cosmic radiation. However, only few biologic markers or associations with disease outcomes have so far been identified. In the present study, 22 long- and 26 medium-haul male Portuguese airline pilots and 36 factory workers who did not fly regularly were investigated. The two groups were comparable in age and diet, were non-smokers, never treated with ionizing radiation and other factors. Cosmic radiation exposure in pilots was quantified based on direct monitoring of 51 flights within Europe, and from Europe to North and South America, and to Africa. Indirect dose estimates in pilots were performed based on the SIEVERT (Système informatisé d'évaluation par vol de l'exposition au rayonnement cosmique dans les transports aériens) software for 6,039 medium- and 1,366 long-haul flights. Medium-haul pilots had a higher cosmic radiation dose rate than long-haul pilots, that is, 3.3 ± 0.2 μSv/h and 2.7 ± 0.3 μSv/h, respectively. Biological tests for oxidative stress on blood and urine, as appropriate, at two time periods separated by 1 year, included measurements of antioxidant capacity, total protein, ferritin, hemoglobin, creatinine and 8-hydroxy-2-deoxyguanosine (8OHdG). Principal components analysis was used to discriminate between the exposed and unexposed groups based on all the biological tests. According to this analysis, creatinine and 8OHdG levels were different for the pilots and the unexposed group, but no distinctions could be made among the medium- and the long-haul pilots. While hemoglobin levels seem to be comparable between the studied groups, they were directly correlated with ferritin values, which were lower for the airline pilots.

Costa, N, Matos S, Gomes da Silva MDR, Pereira MMA.  2013.  Cyclodextrin-Based Ionic Liquids as Enantioselective Stationary Phases in Gas Chromatography, DEC. CHEMPLUSCHEM. 78:1466-1474., Number 12 Abstract
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Guerra, M, Parente F, Santos JP.  2013.  Electron impact ionization cross sections of several ionization stages of Kr, Ar and Fe, Aug 15. International Journal of Mass Spectrometry. 348:1-8.: Elsevier B.V. AbstractWebsite

International Journal of Mass Spectrometry, 348 (2013) 1-8. doi:10.1016/j.ijms.2013.02.011

Guerra, M, Amaro P, Szabo CI, Gumberidze A, Indelicato P, Santos JP.  2013.  Analysis of the charge state distribution in an ECRIS Ar plasma using high-resolution x-ray spectra, Apr 01. Journal of Physics B: Atomic, Molecular and Optical Physics. 46:065701., Number 6 AbstractWebsite
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Almeida, G, Gonzalez J, Rosado L, Vilaça P, Santos TG.  2013.  Advances in NDT and materials characterization by eddy currents, 2013. 46th CIRP Conference on Manufacturing Systems, CIRP CMS 2013. 7:359-364., Setubal Abstract
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