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2017
Lavande, N, Acuna A, Basilio N, Francisco V, Malkhede DD, Garcia-Rio L.  2017.  A journey from calix 4 arene to calix 6 and calix 8 arene reveals more than a matter of size. Receptor concentration affects the stability and stoichiometric nature of the complexes, 2017. Physical Chemistry Chemical Physics. 19(21):13640-13649. AbstractWebsite
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Fernandes, SN, Almeida PL, Monge N, Aguirre LE, Reis D, de Oliveira CLP, Neto AMF, Pieranski P, Godinho MH.  2017.  Mind the Microgap in Iridescent Cellulose Nanocrystal Films, 2017. Advanced MaterialsAdvanced Materials. 29(2):1603560.: John Wiley & Sons, Ltd AbstractWebsite

A new photonic structure is produced from cellulose nanocrystal iridescent films reflecting both right and left circularly polarized light. Micrometer-scale planar gaps perpendicular to the films' cross-section between two different left-handed films' cholesteric domains are impregnated with a nematic liquid crystal. This photonic feature is reversibly tuned by the application of an electric field or a temperature variation.

Sutradhar, M, Rajeshwari, Roy Barman T, Fernandes AR, Paradinha F, Roma-Rodrigues C, Guedes da Silva FMC, Pombeiro AJL.  2017.  Mixed ligand aroylhydrazone and N-donor heterocyclic Lewis base Cu(II) complexes as potential antiproliferative agents, 2017. 175:267-275. AbstractWebsite

A series of four mixed ligand aroylhydrazone and N-donor heterocyclic Lewis base Cu(II) complexes [CuL(X)]2 [L refers to the dianionic form of (5-bromo-2-hydroxybenzylidene)-2-hydroxybenzohydrazide; X=pyrazine (Pz; 1), pyridine (Py; 2), imidazole (Imz; 3) and 3-pyridinecarbonitrile (3-PyCN; 4)] has been synthesized and characterized by elemental analysis, various spectroscopic techniques and X-ray crystallography (for 1, 2 and 4). The antiproliferative effect of complexes 1–4 was examined in 4 human tumor cell lines (ovarian carcinoma (A2780), colorectal carcinoma (HCT116), lung adenocarcinoma (A549) and breast adenocarcinoma (MCF7)) and in normal human primary Fibroblasts. Complex 4 exhibits a high cytotoxic activity against ovarian and colorectal carcinoma cells (A2780, HCT116 respectively), with IC50 much lower than those for normal primary fibroblasts. Complex 4 could induce cell death via apoptosis but not autophagy in colorectal carcinoma cells.

Vinhas, R, Mendes R, Fernandes AR, Baptista PV.  2017.  Nanoparticles—Emerging Potential for Managing Leukemia and Lymphoma, 2017. 5:79. AbstractWebsite

Nanotechnology has become a powerful approach to improve the way we diagnose and treat cancer. In particular, nanoparticles possess unique features for enhanced sensitivity and selectivity for earlier detection of circulating cancer biomarkers. In vivo, nanoparticles enhance the therapeutic efficacy of anticancer agents when compared to conventional chemotherapy, improving vectorization and delivery, and helping to overcome drug resistance. Nanomedicine has been mostly focused on solid cancers due to take advantage from the enhanced permeability and retention (EPR) effect experienced by tissues in the close vicinity of tumors, which enhance nanomedicine’s accumulation and, consequently, improve efficacy. Nanomedicines for leukemia and lymphoma, where EPR effect is not a factor, are addressed differently from solid tumors. Nevertheless, nanoparticles have provided innovative approaches to simple and non-invasive methodologies for diagnosis and treatment in liquid tumors. In this review, we consider the state of the art on different types of nanoconstructs for the management of liquid tumors, from pre-clinical studies to clinical trials. We also discuss the advantages of nanoplatforms for theranostics and the central role played by nanoparticles in this combined strategy.

Santoro, S, Vidorreta IM, Sebastian V, Moro A, Coelhoso IM, Portugal CAM, Lima JC, Desiderio G, Lombardo G, Drioli E, Mallada R, Crespo JG, Criscuoli A, Figoli A.  2017.  A non-invasive optical method for mapping temperature polarization in direct contact membrane distillation, 2017. Journal of Membrane Science. 536:156-166. AbstractWebsite
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Fonseca, SM, Moreira T, Parola AJ, Pinheiro C, Laia CAT.  2017.  PEDOT electrodeposition on oriented mesoporous silica templates for electrochromic devices, 2017. Solar Energy Materials and Solar Cells. 159:94-101. AbstractWebsite
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Mendes, R, Pedrosa P, Lima JC, Fernandes AR, Baptista PV.  2017.  Photothermal enhancement of chemotherapy in breast cancer by visible irradiation of Gold Nanoparticles, 2017. Scientific Reports. 7 AbstractWebsite
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Mendes, R, Pedrosa P, Lima JC, Fernandes AR, Baptista PV.  2017.  Photothermal enhancement of chemotherapy in breast cancer by visible irradiation of Gold Nanoparticles, 2017. 7(1):10872. AbstractWebsite

Photothermal Therapy (PTT) impact in cancer therapy has been increasing due to the enhanced photothermal capabilities of a new generation of nanoscale photothermal agents. Among these nanoscale agents, gold nanoshells and nanorods have demonstrated optimal properties for translation of near infra-red radiation into heat at the site of interest. However, smaller spherical gold nanoparticles (AuNPs) are easier to produce, less toxic and show improved photoconversion capability that may profit from the irradiation in the visible via standard surgical green lasers. Here we show the efficient light-to-heat conversion of spherical 14 nm AuNPs irradiated in the visible region (at the surface plasmons resonance peak) and its application to selectively obliterate cancer cells. Using breast cancer as model, we show a synergistic interaction between heat (photoconversion at 530 nm) and cytotoxic action by doxorubicin with clear advantages to those of the individual therapy approaches.

Pedrosa, P, Heuer-Jungemann A, Kanaras AG, Fernandes AR, Baptista PV.  2017.  Potentiating angiogenesis arrest in vivo via laser irradiation of peptide functionalised gold nanoparticles, 2017. 15(1):85. AbstractWebsite

Anti-angiogenic therapy has great potential for cancer therapy with several FDA approved formulations but there are considerable side effects upon the normal blood vessels that decrease the potential application of such therapeutics. Chicken chorioallantoic membrane (CAM) has been used as a model to study angiogenesis in vivo. Using a CAM model, it had been previously shown that spherical gold nanoparticles functionalised with an anti-angiogenic peptide can humper neo-angiogenesis.

Roma-Rodrigues, C, Pereira F, Alves de Matos AP, Fernandes M, Baptista PV, Fernandes AR.  2017.  Smuggling gold nanoparticles across cell types – A new role for exosomes in gene silencing, 2017. 13(4):1389-1398. AbstractWebsite

Once released to the extracellular space, exosomes enable the transfer of proteins, lipids and RNA between different cells, being able to modulate the recipient cells' phenotypes. Members of the Rab small GTP-binding protein family, such as RAB27A, are responsible for the coordination of several steps in vesicle trafficking, including budding, mobility, docking and fusion. The use of gold nanoparticles (AuNPs) for gene silencing is considered a cutting-edge technology. Here, AuNPs were functionalized with thiolated oligonucleotides anti-RAB27A (AuNP@PEG@anti-RAB27A) for selective silencing of the gene with a consequent decrease of exosomes´ release by MCF-7 and MDA-MB-453 cells. Furthermore, communication between tumor and normal cells was observed both in terms of alterations in c-Myc gene expression and transportation of the AuNPs, mediating gene silencing in secondary cells.

Sousa, DM, Lima JC, Ferreira I.  2017.  Synthesis of Cadmium Selenide Quantum Dots, Using 2,2-Bipyridine as a Capping and Phase Transfer Agent, 2017. Chemistryselect. 2(3):1271-1274. AbstractWebsite
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Carrera, GVSM, Raymundo A, Fernandes FMB, Jordao N, Sousa I, da Ponte MN, Branco LC.  2017.  Tetramethylguanidine-based gels and colloids of cellulose, 2017. Carbohydrate Polymers. 169:58-64. AbstractWebsite
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Sousa, JR, Silveira CM, Fontes P, Roma-Rodrigues C, Fernandes AR, Van Driessche G, Devreese B, Moura I, Moura JJG, Almeida GM.  2017.  Understanding the response of Desulfovibrio desulfuricans ATCC 27774 to the electron acceptors nitrate and sulfate - biosynthetic costs modulate substrate selection, 2017. 1865(11, Part A):1455-1469. AbstractWebsite
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Seixas, J, Fortes P, Simões S, Gouveia JP.  2017.  Trajetórias de descarbonização e impactos na matriz energética [Pathways for the decarbonisation and impact in the energy matrix] , 14 December. Conferência A transição energética na Península Ibérica - Associação Portuguesa de Economia da Energia [Conference on the energy transition in the Iberian Peninsula of the APEEN – Portuguese Association for Energy Economy]. , ISCTE. Instituto Universitário de Lisboa. Lisboa, Portugal: APEEN
Simoes, SG, Marogna N, Fortes P.  2017.  Assessing water needs for power production in Iberian Peninsula at watershed level, 13 December. ETSAP Workshop on modelling the water-energy nexus. , Zurich, Switzerland: ETH Zurich
Simoes, SG, Barbosa J, Fazendeiro L, Seixas J.  2017.  The Return of H2 – Challenges of Modelling H2 in TIMES, 11-12 December . 72nd Semi-annual ETSAP meeting. , Zurich, Switzerland: ETH Zurich
Marques, AC, Santos L, Dantas JM, Gonçalves A, Casaleiro S, Martins R, Salgueiro CA, Fortunato E.  2017.  Advances in electrochemically active bacteria: Physiology and ecology. Handbook of Online and Near-real-time Methods in Microbiology. : CRC Press Abstract

The discovery of microorganisms with the ability of Extracellular Electron Transfer (EET), nearly three decades ago, sparked interest due to their ability to be used in diverse applications that can range from bioremediation to electricity production in Microbial Fuel Cells (MFC). Microbial respiration is based on electron transfer from a donor to an electron acceptor, through a series of stepwise electron transfer events that generate the necessary metabolic energy. Some microorganisms, such as Pseudomonas species, Shewanella putrefaciens or Geothrix fermentans are able to produce electrochemical mediators to increase the EET. The mechanical stability of the biofilm is provided by the biofilm matrix, a hydrated extracellular polymeric matrix that encases the biofilm cells. The biofilm matrix could potentially offer a resistance pathway to EET unless bacteria develop strategies to increase its conductivity. MFC devices currently being used and studied do not generate sufficient power to support widespread and cost-effective applications.

Teotónio, C, Fortes P, Roebeling P, Rodriguez M, Robaina-Alves M.  2017.  Assessing the impacts of climate change on hydropower generation and the power sector in Portugal: A partial equilibrium approach. Renewable and Sustainable Energy Reviews. 74:788-799.
Fortes, P, Proença S, Simoes SG, Seixas J.  2017.  Can green power lead to green growth? A study for Portugal 15th IAEE European Conference "Heading towards sustainable energy systems: Evolution or Revolution?". , Vienna, Austria. 3-6 September, https://www.aaee.at/iaee2017/: Hofburg Congress Center
Berride, F, Troche-Pesqueira E, Feio G, Cabrita EJ, Sierra T, Navarro-Vázquez A, Cid MM.  2017.  Chiral amplification of disodium cromoglycate chromonics induced by a codeine derivative. Soft Matter. 13(38):6810-6815. AbstractWebsite

Chromonic liquid crystals (CLC) are lyotropic phases formed by discotic mesogens in water. Simple chiral dopants such as amino acids have been reported to turn chromonic liquid crystals into their cholesteric counterparts. Here we report a chirality amplification effect in the nematic phase of a 9 wt% disodium cromoglycate (DSCG) lyotropic liquid crystal (LLC) upon doping with a water-soluble codeine derivative. The transition on cooling the isotropic to the nematic phase showed the presence of homochiral spindle-shaped droplets (tactoids). NMR DOSY experiments on a triple gradient probe revealed a small degree of diffusion anisotropy for the alkaloid embedded in the liquid crystal structure. These results in combination with XRD, CD and POM experiments agree with a supramolecular aggregation model based on simple columnar stacks.

Matias, SC, Lourenço NMT, Fonseca JP, Cordas CM.  2017.  Comparative electrochemical behavior of cytochrome c on aqueous solutions containing choline-based room temperature ionic liquids. ChemistrySelect. 2:8701–8705.Website
Peixoto, D, Figueiredo M, Gawande MB, Corvo MC, Vanhoenacker G, Afonso CAM, Ferreira LM, Branco PS.  2017.  DEVELOPMENTS IN THE REACTIVITY OF 2-METHYL IMIDAZOLIUM SALTS. The Journal of Organic Chemistry. 82(12):6232–6241.: American Chemical Society AbstractWebsite

Unexpected and unusual reactivity of 2-methylimidazolium salts toward aryl-N-sulfonylimines and aryl aldehydes is here reported. Upon reaction with aryl-N-sulfonylimines, the addition product, arylethyl-2-imidazolium-1-tosylamide (3), is formed with moderate to good yields, while upon reaction with aldehydes, the initial addition product (6) observed in NMR and HPLC–MS experimental analysis is postulated by us as an intermediate to the final conversion to carboxylic acids. Studies in the presence and absence of molecular oxygen allow us to conclude that the imidazolium salts is crucial for the oxidation. A detailed mechanistic study was carried out to provide insights regarding this unexpected reactivity.

Delgado-Lima, A, Borges JP, Ferreira I, Machado A.  2017.  Fluorescent and conductive cellulose acetate-based membranes with porphyrins. Materials today Communications. 11:26-37. AbstractWebsite

The unique properties of electrospun nanofibers combined with functional compounds allow the preparation of novelty materials that can be employed in a wide range of applications. Among a vast number of polymers, Cellulose Acetate (CA) it is considered easy to electrospun and it was employed as the polymeric matrix, where free and iridium-porphyrins were incorporated. Two different solvent systems were employed according to the porphyrin used, and the best dispersion level on both the electrospun solution and the membranes, was achieved with the iridium porphyrin. The nanofibers with this porphyrin also exhibited electrical properties, while the fluorescence was quenched by the presence of specific axial ligands.

Delgado-Lima, A, Borges JP, Ferreira IM, Machado AV.  2017.  Fluorescent and conductive cellulose acetate-based membranes with porphyrins. Materials Today Communications. 11:26-37. AbstractWebsite

The unique properties of electrospun nanofibers combined with functional compounds allow the preparation of novelty materials that can be employed in a wide range of applications. Among a vast number of polymers, Cellulose Acetate (CA) it is considered easy to electrospun and it was employed as the polymeric matrix, where free and iridium-porphyrins were incorporated. Two different solvent systems were employed according to the porphyrin used, and the best dispersion level on both the electrospun solution and the membranes, was achieved with the iridium porphyrin. The nanofibers with this porphyrin also exhibited electrical properties, while the fluorescence was quenched by the presence of specific axial ligands.

Mendes, R, Fernandes AR, Baptista PV.  2017.  Gold Nanoparticle Approach to the Selective Delivery of Gene Silencing in Cancer—The Case for Combined Delivery? Genes. 3(8):94. Abstract

Gene therapy arises as a great promise for cancer therapeutics due to its potential to silence genes involved in tumor development. In fact, there are some pivotal gene drivers that suffer critical alterations leading to cell transformation and ultimately to tumor growth. In this vein, gene silencing has been proposed as an active tool to selectively silence these molecular triggers of cancer, thus improving treatment. However, naked nucleic acid (DNA/RNA) sequences are reported to have a short lifetime in the body, promptly degraded by circulating enzymes, which in turn speed up elimination and decrease the therapeutic potential of these drugs. The use of nanoparticles for the effective delivery of these silencers to the specific target locations has allowed researchers to overcome this issue. Particularly, gold nanoparticles (AuNPs) have been used as attractive vehicles for the target-specific delivery of gene-silencing moieties, alone or in combination with other drugs. We shall discuss current trends in AuNP-based delivery of gene-silencing tools, considering the promising road ahead without overlooking existing concerns for their translation to clinics