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2015
Velasco, LF, Gomis-Berenguer A, Lima JC, Ania CO.  2015.  Tuning the Surface Chemistry of Nanoporous Carbons for Enhanced Nanoconfined Photochemical Activity. Chemcatchem. 7:3012-3019., Number 18 AbstractWebsite
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Palma, AS, Liu Y, Zhang H, Zhang Y, McCleary BV, Yu G, Huang Q, Guidolin LS, Ciocchini AE, Torosantucci A, Wang D, Carvalho AL, Fontes CM, Mulloy B, Childs RA, Feizi T, Chai W.  2015.  Unravelling glucan recognition systems by glycome microarrays using the designer approach and mass spectrometry. Mol Cell Proteomics. AbstractWebsite

Glucans are polymers of D-glucose with differing linkages in linear or branched sequences. They are constituents of microbial and plant cell-walls and involved in important bio-recognition processes including immunomodulation, anti-cancer activities, pathogen virulence and plant cell-wall biodegradation. Translational possibilities for these activities in medicine and biotechnology are considerable. High-throughput micro-methods are needed to screen proteins for recognition of specific glucan sequences as a lead to structure-function studies and their exploitation. We describe construction of a glucome microarray, the first sequence-defined glycome-scale microarray, using a designer approach from targeted ligand-bearing glucans in conjunction with a novel high-sensitivity mass spectrometric sequencing method, as a screening tool to assign glucan recognition motifs. The glucome microarray comprises 153 oligosaccharide probes with high purity, representing major sequences in glucans. The negative-ion electrospray tandem mass spectrometry with collision-induced dissociation was used for complete linkage analysis of gluco-oligosaccharides in linear homo and hetero and branched sequences. The system is validated using antibodies and carbohydrate-binding modules known to target α- or β-glucans in different biological contexts, extending knowledge on their specificities, and applied to reveal new information on glucan recognition by two signalling molecules of the immune system against pathogens: Dectin-1 and DC-SIGN. The sequencing of the glucan oligosaccharides by the MS method and their interrogation on the microarrays provides detailed information on linkage, sequence and chain length requirements of glucan-recognizing proteins, and are a sensitive means of revealing unsuspected sequences in the polysaccharides.

Palma, SI, Rodrigues CA, Carvalho A, Morales Mdel P, Freitas F, Fernandes AR, Cabral JM, Roque AC.  2015.  A value-added exopolysaccharide as a coating agent for MRI nanoprobes. Nanoscale. 7:14272-83., Number 34 AbstractWebsite

Fucopol, a fucose-containing exopolysaccharide (EPS) produced by the bacterium Enterobacter A47 DSM 23139 using glycerol as a carbon source, was employed as a new coating material for iron oxide magnetic nanoparticles (MNPs). The coated particles were assessed as nanoprobes for cell labeling by Magnetic Resonance Imaging (MRI). The MNPs were synthesized by a thermal decomposition method and transferred to an aqueous medium by a ligand-exchange reaction with meso-2,3-dimercaptosuccinic acid (DMSA). Covalent binding of EPS to DMSA-stabilized nanoparticles (MNP-DMSA) resulted in a hybrid magnetic-biopolymeric nanosystem (MNP-DMSA-EPS) with a hydrodynamic size of 170 nm, a negative surface charge under physiological conditions and transverse to longitudinal relaxivity ratio, r2/r1, of 148. In vitro studies with two human cell lines (colorectal carcinoma - HCT116 - and neural stem/progenitor cells - ReNcell VM) showed that EPS promotes internalization of nanoparticles in both cell lines. In vitro MRI cell phantoms showed a superior performance of MNP-DMSA-EPS in ReNcell VM, for which the iron dose-dependent MRI signal drop was obtained at relatively low iron concentrations (12-20 mug Fe per ml) and short incubation times. Furthermore, ReNcell VM multipotency was not affected by culture in the presence of MNP-DMSA or MNP-DMSA-EPS for 14 days. Our study suggests that Fucopol-coated MNPs represent useful cell labeling nanoprobes for MRI.

Ullaha, S, Matteis DF, Branquinho R, Fortunato E, Martins R, Davoli I.  2015.  {A combination of solution synthesis solution combustion synthesis for highly conducting and transparent Aluminum Zinc Oxide thin films}. 2015 IEEE 15th International Conference on Nanotechnology (IEEE-NANO). :144–147. Abstract

Aluminum Zinc Oxide has been extensively investigated as a cheap alternative to transparent conducting tin oxide films for electronic and optoelectronic applications. Thin films of Aluminum Zinc Oxide have been developed successfully through a combination of solution combustion synthesis and solution synthesis. Zn(NO3)3·6H2O as metal source was dissolved in 2-methoxyethanol as solvent through combustion synthesis with Urea as fuel while dopant source of AlCl3·6H2O was mixed separately in solvent to avoid aluminum oxide formation in the films. Precursor solutions were obtained mixing Zn {&} Al separate solutions in 9:1, 8:2, and 7:3 ratios respectively with oxide, fuel and dopant concentrations of 0.5, 0.25, 0.1, and 0.05 M. The film stacks have been prepared through spin-coating with heating at 400°C for 10 minutes after each deposition to remove residuals and evaporate solvents. Thermal annealing in oven at 600°C for 1 hour followed by rapid thermal annealing at 500°C {&} 600°C first in vacuum and then in N2-5{%}H2 environment respectively for 10 minutes each reduced the resistivity of film stacks. Film stack with 10 layers for an average thickness of 0.5$μ$m gave the best Hall Effect resistivity of 3.2 × 10-2 $Ømega$-cm in the case of 0.5M solution with Zn:Al mixing ratio of 9:1 for RTA annealings at 600°C with an average total transparency of 80 {%} in the wavelength range of 400-1200 nm. The results show a clear trend that increasing the amount of ingredients resistivity could further be decreased.

Moniz, A.  2015.  {Assessing Technologies: Global Patterns of Trust and Distrust. Report on one session at the XVIII World Congress of Sociology}. EconStor Open Access Articles. :119-121. AbstractWebsite

Technology assessment (TA) had never been treated as a relevant topic within the International Sociological Association (ISA) before. The first steps towards establishing this association were taken in 1948, at the initiative of the Social Science Department of UNESCO. Its formal foundation was in 1949. The World Congress of Sociology in Japan was hopefully the beginning of continuous integration of TA into the thematic sessions within the ISA.

Nandy, S, Thapa R, Kumar M, Som T, Bundaleski N, Teodoro OMND, Martins R, Fortunato E.  2015.  {Efficient Field Emission from Vertically Aligned Cu2O1-delta(111) Nanostructure Influenced by Oxygen Vacancy}. ADVANCED FUNCTIONAL MATERIALS. 25:947–956., Number 6 Abstract
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Fernandes, M, Leones R, Costa AMS, Silva MM, Pereira S, Mano JF, Fortunato E, Rego R, {de Zea Bermudez} V.  2015.  {Electrochromic devices incorporating biohybrid electrolytes doped with a lithium salt, an ionic liquid or a mixture of both}. Electrochimica Acta. 161:226–235.: Elsevier Ltd AbstractWebsite
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Kololuoma, T, Leppäniemi J, Majumdar H, Branquinho R, Herbei-Valcu E, Musat V, Martins R, Fortunato E, Alastalo A.  2015.  {Gravure printed sol–gel derived AlOOH hybrid nanocomposite thin films for printed electronics}. J. Mater. Chem. C. 3:1776–1786., Number 8 AbstractWebsite
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Vicente, A, Águas H, Mateus T, Araújo A, Lyubchyk A, Siitonen S, Fortunato E, Martins R.  2015.  {Solar cells for self-sustainable intelligent packaging}. J. Mater. Chem. A. 3:13226–13236., Number 25 AbstractWebsite
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Wojcik, PJ, Santos L, Pereira L, Martins R, Fortunato E.  2015.  {Tailoring nanoscale properties of tungsten oxide for inkjet printed electrochromic devices}. Nanoscale. 7:1696–1708., Number 5: Royal Society of Chemistry AbstractWebsite

This paper focuses on the engineering procedures governing the synthesis of tungsten oxide nanocrystals and the formulation of printable dispersions for electrochromic applications. By that means, we aim to stress the relevancy of a proper design strategy that results in improved physicochemical properties of nanoparticle loaded inks. In the present study inkjet printable nanostructured tungsten oxide particles were successfully synthesized via hydrothermal processes using pure or acidified aqueous sol-gel precursors. Based on the proposed scheme, the structure and morphology of the nanoparticles were tailored to ensure the desired printability and electrochromic performance. The developed nanomaterials with specified structures effectively improved the electrochemical response of printed films, resulting in 2.5 times higher optical modulation and 2 times faster coloration time when compared with pure amorphous films.

Branquinho, R, Salgueiro D, Santa A, Kiazadeh A, Barquinha P, Pereira L, Martins R, Fortunato E.  2015.  {Towards environmental friendly solution-based ZTO/AlOx TFTs}. SEMICONDUCTOR SCIENCE AND TECHNOLOGY. 30, Number 2, SI Abstract
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2014
Jesus, AR, Dias C, Matos AM, de Almeida RFM, Viana AS, Marcelo F, Ribeiro RT, Macedo MP, Airoldi C, Nicotra F, Martins A, Cabrita EJ, Jimenez-Barbere J, Rauter AP.  2014.  Exploiting the Therapeutic Potential of 8-beta-D-Glucopyranosylgenistein: Synthesis, Antidiabetic Activity, and Molecular Interaction with Islet Amyloid Polypeptide and Amyloid beta-Peptide (1-42), {NOV 27}. Journal of Medicinal Chemistry. 57:9463-9472., Number {22} Abstract

8-β-d-Glucopyranosylgenistein (1), the major component of Genista tenera, was synthesized and showed an extensive therapeutical impact in the treatment of STZ-induced diabetic rats, producing normalization of fasting hyperglycemia and amelioration of excessive postprandial glucose excursions and and increasing β-cell sensitivity, insulin secretion, and circulating insulin within 7 days at a dose of 4 (mg/kg bw)/day. Suppression of islet amyloid polypeptide (IAPP) fibril formation by compound 1 was demonstrated by thioflavin T fluorescence and atomic force microscopy. Molecular recognition studies with IAPP and Aβ1-42 employing saturation transfer difference (STD) confirmed the same binding mode for both amyloid peptides as suggested by their deduced epitope. Insights into the preferred conformation in the bound state and conformers' geometry resulting from interaction with Aβ1-42 were also given by STD, trNOESY, and MM calculations. These studies strongly support 8-β-d-glucopyranosylgenistein as a promising molecular entity for intervention in amyloid events of both diabetes and the frequently associated Alzheimer's disease.

Santos, JP, Martins MC, Costa AM, Marques JP, Indelicato P, Parente F.  2014.  Theoretical determination of K X-ray transition energy and probability values for highly charged ions of lanthanum and cerium, Sep 11. The European Physical Journal D. 68:244., Number 9 AbstractWebsite
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Pina, L, Veiga L, Hicks M.  2014.  Rubah: DSU for Java on a stock JVM, sep. ACM Conference on Object-Oriented Programming Languages, Systems, and Applications (OOPSLA 2014). : ACM Abstract2014-oopsla-pina-core-a.pdf

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Cabral, {RM }, Baptista P.  2014.  Anti-cancer precision theranostics: a focus on multifunctional gold nanoparticles, nov. Expert Review Of Molecular Diagnostics. 14:1041–1052., Number 8: Expert Reviews Abstract

Gold nanoparticles have been appointed as cutting-edge platforms for combined diagnostic and therapeutic approaches due to their exquisite physicochemical and optical properties. In particular, their potential benefits in cancer settings are enormous, as they can serve as targeted vehicles for controlled drug release, photothermal therapy and gene therapy, as well as contrast imaging agents to allow for real-time monitoring of both disease and therapeutic progression. These theranostic platforms represent powerful image-guided therapeutics, tailored to maximize individual patient benefit and with the ability to significantly minimize toxic side effects. Here the authors review some of the recent advances on the development of gold nanoparticle conjugates for combined diagnostics and therapy, while reflecting on the obstacles toward translational research.

Carlos, {FF}, Flores O, Doria G, Baptista P.  2014.  Characterization of genomic single nucleotide polymorphism via colorimetric detection using a single gold nanoprobe, nov. Analytical Biochemistry. 465:1–5.: ACADEMIC PRESS INC ELSEVIER SCIENCE Abstract

Identification of specific nucleic acid sequences mediated by gold nanoparticles derivatized thiol-modified oligonucleotides (Au-nanoprobes) has been proven to be a useful tool in molecular diagnostics. Here, we demonstrate that, on optimization, detection may be simplified via the use of a single Au-nanoprobe to detect a single nucleotide polymorphism (SNP) in homo- or heterozygote condition. We validated this non-cross-linking approach through the analysis of 20 clinical samples using a single specific Au-nanoprobe for an SNP in the FTO (fat mass and obesity-associated) gene against direct DNA sequencing. Sensitivity, specificity, and limit of detection CLOD) were determined, and statistical differences were calculated by one-way analysis of variance (ANOVA) and a post hoc Tukey's test to ascertain whether there were any differences between Au-nanoprobe genotyped groups. For the first time, we show that the use of a single Au-nanoprobe can detect SNP for each genetic status (wild type, heterozygous, or mutant) with high degrees of sensitivity (87.50%) and specificity (91.67%). (c) 2014 Elsevier Inc. All rights reserved.

Larguinho, M, Cordeiro A, Diniz M, Costa {PM }, Baptista P.  2014.  Metabolic and histopathological alterations in the marine bivalve Mytilus galloprovincialis induced by chronic exposure to acrylamide, nov. Environmental Research. 135:55–62.: Academic Press | Elsevier Abstract

Although the neurotoxic and genotoxic potential of acrylamide has been established in freshwater fish, the full breadth of the toxicological consequences induced by this xenobiotic has not yet been disclosed, particularly in aquatic invertebrates. To assess the effects of acrylamide on a bivalve model, the Mediterranean mussel (Mytilus galloprovincialis), two different setups were accomplished: 1) acute exposure to several concentrations of waterborne acrylamide to determine lethality thresholds of the substance and 2) chronic exposure to more reduced acrylamide concentrations to survey phases I and II metabolic endpoints and to perform a whole-body screening for histopathological alterations. Acute toxicity was low (LC50 approximate to 400 mg/L). However, mussels were responsive to prolonged exposure to chronic concentrations of waterborne acrylamide (1-10 mg/L), yielding a significant increase in lipid peroxidation plus EROD and GST activities. Still, total anti-oxidant capacity was not exceeded. In addition, no neurotoxic effects could be determined through acetylcholine esterase (AChE) activity. The findings suggest aryl-hydrocarbon receptor (Ahr)-dependent responses in mussels exposed to acrylamide, although reduced comparatively to vertebrates. No significant histological damage was found in digestive gland or gills but female gonads endured severe necrosis and oocyte atresia. Altogether, the results indicate that acrylamide may induce gonadotoxicity in mussels, although the subject should benefit from further research. Altogether, the findings suggest that the risk of acrylamide to aquatic animals, especially molluscs, may be underestimated. (C) 2014 Elsevier Inc. All rights reserved.

Pedrosa, P, Veigas B, Machado D, Couto I, Viveiros M, Baptista {PV}.  2014.  Gold nanoprobes for multi loci assessment of multi-drug resistant tuberculosis, may. Tuberculosis. 94:332–337., Number 3: Churchill Livingstone Abstract

Tuberculosis, still one of the leading human infectious diseases, reported 8.7 million new cases in 2011 alone. Also, the increasing rate of multidrug-resistant tuberculosis (MDRTB) and its treatment difficulties pose a serious public health threat especially in developing countries. Resistance to isoniazid and rifampicin, first line antibiotics, is commonly associated with point mutations in katG, inhA and rpoB genes of Mycobacterium tuberculosis complex (MTBC). Therefore, the development of cheap, fast and simple molecular methods to assess susceptibility profiles would have a huge impact in the capacity of early diagnosis and treatment of MDRTB. Gold nanoparticles functionalized with thiol-modified oligonucleotides (Au-nanoprobes) have shown the potential to provide a rapid and sensitive detection method for MTBC and single base mutations associated with antibiotic resistance, namely the characterization of the three most relevant codons in rpoB gene associated to rifampicin resistance. Here we extend the Au-nanoprobe approach towards discriminating specific mutations within inhA and rpoB genes in PCR amplified DNA from isolates. Using a multiplex PCR reaction for these two genes, it is possible to assess both loci in parallel, and extend the potential of the Au-nanoprobe method to MDRTB molecular characterization with special application in the most frequent Portuguese genotypes. (C) 2014 Elsevier Ltd. All rights reserved.

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, mar. Nanotechnology. 25, Number 9: IOP Publishing Abstract

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.

Gaspar, D, Fernandes SN, dea Oliveira G, 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.}, mar. 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 \{$\backslash$textquoteright\}interstrate\{$\backslash$textquoteright\} 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 (>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.}, mar. Nanotechnology. 25:094007., 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 ION/IOFF ratio close to 10(5).

Rahangdale, HV, Guerra M, Das PK, De S, Santos JP, Mitra D, Saha S.  2014.  Determination of subshell-resolved <span class="aps-inline-formula"><math><mi>L</mi></math></span>-shell-ionization cross sections of gold induced by 15–40-keV electrons, Jun 14. Physical Review A. 89:052708., Number 5 AbstractWebsite
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Amaro, P, Szabo CI, Schlesser S, Gumberidze A, Kessler EG, Henins A, Le Bigot EO, Trassinelli M, Isac JM, Travers P, Guerra M, Santos JP, Indelicato P.  2014.  A vacuum double-crystal spectrometer for reference-free X-ray spectroscopy of highly charged ions, Jun 01. Radiation Physics and Chemistry. 98:132-149., Number C: Elsevier AbstractWebsite

Radiation Physics and Chemistry, 98 + (2014) 132-149. doi:10.1016/j.radphyschem.2014.01.015

Conde, J, Bao C, Cui D, Baptista {PV}, Tian F.  2014.  Antibody-drug gold nanoantennas with Raman spectroscopic fingerprints for in vivo tumour theranostics, jun. Journal of Controlled Release. 183:87–93., Number 1: Elsevier Abstract

Inspired by the ability of SERS nanoantennas to provide an integrated platform to enhance disease targeting in vivo, we developed a highly sensitive probe for in vivo tumour recognition with the capacity to target specific cancer biomarkers such as epidermal growth factor receptors (EGFR) on human cancer cells and xenograft tumour models. Here, we used   90 nm gold nanoparticles capped by a Raman reporter, encapsulated and entrapped by larger polymers and a FDA antibody-drug conjugate - Cetuximab (Erbitux®) - that specifically targets EGFR and turns off a main signalling cascade for cancer cells to proliferate and survive. These drug/SERS gold nanoantennas present a high Raman signal both in cancer cells and in mice bearing xenograft tumours. Moreover, the Raman detection signal is accomplished simultaneously by extensive tumour growth inhibition in mice, making these gold nanoantennas ideal for cancer nanotheranostics, i.e. tumour detection and tumour cell inhibition at the same time.