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2018
Lenis-Rojas, OA, Robalo MP, Tomaz AI, Carvalho A, Fernandes AR, Marques F, Folgueira M, Yanez J, Vazquez-Garcia D, Lopez Torres M, Fernandez A, Fernandez JJ.  2018.  Ru(II)( p-cymene) Compounds as Effective and Selective Anticancer Candidates with No Toxicity in Vivo, 2018. Inorg Chem. 57(21):13150-13166. AbstractWebsite

Ruthenium(II) complexes are currently considered a viable alternative to the widely used platinum complexes as efficient anticancer agents. We herein present the synthesis and characterization of half-sandwich ruthenium compounds with the general formula [Ru( p-cymene)(L-N,N)Cl][CF3SO3] (L = 3,6-di-2-pyridyl-1,2,4,5-tetrazine (1) 6,7-dimethyl-2,3-bis(pyridin-2-yl)quinoxaline (2)), which have been synthesized by substitution reactions from the precursor dimer [Ru( p-cymene)(Cl)(mu-Cl)]2 and were characterized by elemental analysis, mass spectrometry, (1)H NMR, UV-vis, and IR spectroscopy, conductivity measurements, and cyclic voltammetry. The molecular structure for complex 2 was determined by single-crystal X-ray diffraction. The cytotoxic activity of these compounds was evaluated against human tumor cells, namely ovarian carcinoma A2780 and breast MCF7 and MDAMB231 adenocarcinoma cells, and against normal primary fibroblasts. Whereas the cytotoxic activity of 1 is moderate, IC50 values found for 2 are among the lowest previously reported for Ru( p-cymene) complexes. Both compounds present no cytotoxic effect in normal human primary fibroblasts when they are used at the IC50 concentration in A2780 and MCF7 cancer cells. Their antiproliferative capacity is associated with a combined mechanism of apoptosis and autophagy. A strong interaction with DNA was observed for both with a binding constant value of the same magnitude as that of the classical intercalator [Ru(phen)2(dppz)](2+). Both complexes bind to human serum albumin with moderate to strong affinity, with conditional binding constants (log Kb) of 4.88 for complex 2 and 5.18 for complex 1 in 2% DMSO/10 mM Hepes pH7.0 medium. The acute toxicity was evaluated in zebrafish embryo model using the fish embryo acute toxicity test (FET). Remarkably, our results show that compounds 1 and 2 are not toxic/lethal even at extremely high concentrations. The novel compounds reported herein are highly relevant antitumor metallodrug candidates, given their in vitro cytotoxicity toward cancer cells and the lack of in vivo toxicity.

Maron, A, Czerwinska K, Machura B, Raposo L, Roma-Rodrigues C, Fernandes AR, Malecki JG, Szlapa-Kula A, Kula S, Krompiec S.  2018.  Spectroscopy, electrochemistry and antiproliferative properties of Au(iii), Pt(ii) and Cu(ii) complexes bearing modified 2,2':6',2''-terpyridine ligands, 2018. Dalton Trans. 47(18):6444-6463. AbstractWebsite

Structural, spectroscopic and electrochemical properties of six complexes [AuCl(L1)](PF6)2.CH3CN (1), [AuCl(L2)](PF6)2 (2), [PtCl(L1)](BPh4).CH3CN (3), [PtCl(L2)](SO3CF3) (4), [CuCl2(L1)] (5) and [CuCl2(L2)].CH3CN (6) with modified 2,2':6',2''-terpyridine ligands, 4'-(4-methoxyphenyl)-2,2':6',2''-terpyridine (L1) and 4'-(4-methoxynaphthalen-1-yl)-2,2':6',2''-terpyridine (L2) were thoroughly investigated and a significant role of the substituent (4-methoxyphenyl or 4-methoxynaphthalen-1-yl) and the metal center was demonstrated. The naphthyl-based substituent was found to increase the emission quantum yield of the luminescent Au(iii) and Pt(ii) complexes. Furthermore, the antiproliferative potential of the reported complexes was examined towards human colorectal (HCT116) and ovarian (A2780) carcinoma cell lines as well as towards normal human fibroblasts. The Au(iii) complex 2 and Cu(ii) complex 5 were found to have a higher antiproliferative effect on HCT116 colorectal and A2780 ovarian carcinoma cells when compared with the Pt(ii) complex with the same ligand (4). The order of cytotoxicity in both cell lines is 2 > 6 > 1 > 3 > 4. Complex 2 seems to be more cytotoxic towards HCT116 and A2780 cancer cell lines with IC50 values 300x and 130x higher in normal human fibroblasts compared to the respective cancer cells. The viability loss induced by the complexes agrees with Hoechst 33258 staining and the typical morphological apoptotic characteristics like chromatin condensation and nuclear fragmentation and flow cytometry assay. The induction of apoptosis correlates with the induction of reactive oxygen species (ROS). Fluorescence microscopy analysis indicates that after 3 h of incubation, complexes 1-4 are localized inside HCT116 cells and the high levels of internalization correlate with their cytotoxicity.

Bathula, C, Roma-Rodrigues C, Chauhan J, Fernandes AR, Sen S.  2018.  Synthesis of tetrahydro-1H-indolo[2,3-b]pyrrolo[3,2-c]quinolones via intramolecular oxidative ring rearrangement of tetrahydro-β-carbolines and their biological evaluation, 2018. New Journal of Chemistry. 42(8):6538-6547. AbstractWebsite

A simple oxidative ring rearrangement of diversely substituted 1-(2-amminoaryl)-tetrahydro-β-carbolines has been developed to generate architecturally interesting tetrahydro-1H-indolo[2,3-b]pyrrolo[3,2-c]quinolones. This unique transformation involves four reaction centers (aniline, C1-carboline and C2/C3 of indole) and utilizes tert-butylhypochlorite as the reagent. The generic nature of the reaction was demonstrated by the synthesis of a wide variety of analogs 9a–j. A putative reaction mechanism was proposed. Cytotoxicity screening of these compounds against three human cancer cells (A2780 ovarian and HCT116 colorectal carcinoma cell lines and A549 lung adenocarcinoma cell line) revealed selective inhibition of proliferation of the A2780 human ovarian carcinoma cell line by one of the molecules 9a with an IC50 of 14 μM. No cytotoxic activity was observed in human normal fibroblasts for concentrations up to 100 μM. Compound 9a induced hyperpolarization of the mitochondrial membrane potential of the A2780 cell line leading to an increase of reactive oxygen species (ROS) that trigger cell death via apoptosis. Interestingly, compound 9a was also able to induce cell death via autophagy. Compounds that induce apoptosis and autophagy, thus leading to cancer cells’ death, are good candidates for cancer therapy.

Peixoto, D, Figueiredo M, Malta G, Roma-Rodrigues C, Baptista PV, Fernandes AR, Barroso S, Carvalho AL, Afonso CAM, Ferreira LM, Branco PS.  2018.  Synthesis, Cytotoxicity Evaluation in Human Cell Lines and in Vitro DNA Interaction of a Hetero-Arylidene-9(10H)-Anthrone, 2018. 2018(4):545-549. AbstractWebsite

A new and never before reported hetero-arylidene-9(10H)-anthrone structure (4) was unexpectedly isolated on reaction of 1,2-dimethyl-3-ethylimidazolium iodide (2) and 9-anthracenecarboxaldehyde (3) under basic conditions. Its structure was unequivocally confirmed by X-ray crystallography. No cytotoxicity in human healthy fibroblasts and in two different cancer cell lines was observed, indicating its applicability in biological systems. Compound 4 interacts with CT-DNA by intercalation between the adjacent base pairs of DNA with a high binding affinity [Kb = 2.0 (±0.20) × 105 m–1], which is 10 × higher than that described for doxorubicin [Kb = 3.2 (±0.23) × 104 m–1]. Furthermore, compound 4 quenches the fluorescence emission of a GelRed–CT-DNA system with a quenching constant (KSV) of 3.3 (±0.3) × 103 m–1 calculated by the Stern–Volmer equation.

Dias, D, Bernardo M, Lapa N, Pinto F, Matos I, Fonseca I.  2018.  Activated carbons from the Co-pyrolysis of rice wastes for Cr(III) removal. Chemical Engineering Transactions. 65:601-606.
Krings, B-J, Weinberger N.  2018.  Assistant without Master? Some Conceptual Implications of Assistive Robotics in Health Care Technologies. 18(1) AbstractWebsite

The subject of “technical assistants” in inpatient care is currently being widely discussed in scientific and public circles. In many cases, though, it has become apparent that the umbrella term “assistive technologies”, also in the context of robotics, is very contrived. Against this background, the authors of this article reflect on the meaning of “assistance” in socio-technical systems, and critically review its relevance. To understand and demonstrate “assistive” functions, it is essential to establish a frame of reference. The re-evaluation of an empirical study of people with dementia in inpatient care has revealed the functional character of technical assistance systems. The results, however, show that the theoretical debate on the social and organisational function of “assistance” in these technical fields is still lacking. Therefore, the reflections in this paper may also provide some starting points for this debate.

Lopes, R, Magalhães P, Gouveia JP, Aelenei D, Lima C, Martins J.  2018.  A case study on the impact of nearly Zero-Energy Buildings on distribution transformer aging. Energy. 157:669-678.
Szymczak, P, Filipe SR, Covas G, Vogensen FK, Neves AR, Janzen T.  2018.  Cell wall glycans mediate recognition of the dairy bacterium Streptococcus thermophilus by bacteriophages. Applied and Environmental Microbiology. 84(23):e01847-18.
Ropio, I, Baptista AC, Nobre JP, Correia J, Belo F, Taborda S, Faustino MBM, Borges JP, Kovalenko A, Ferreira I.  2018.  Cellulose paper functionalised with polypyrrole and poly(3,4-ethylenedioxythiophene) for paper battery electrodes. Org Electron. AbstractWebsite

A simple process of commercial paper functionalisation via in situ polymerisation of conductive polymers onto cellulose fibres was investigated and applied as electrodes in paper-based batteries. The functionalisation involved polypyrrole (PPy) and Poly (3,4-ethylenedioxythiophene) (PEDOT) as conductive polymers with the process of functionalisation optimised for each polymer individually with respect to oxidant-to-monomer ratios and polymerisation times and temperature. Paper with conductivity values of 44 mS/cm was obtained by exposing the samples to pyrrole vapour for a period of 30 min at room temperature; however, polymerisation at temperatures of 40 °C lead to higher conductivity values to up 141 mS/cm. Consequently, functionalised PPy and PEDOT papers were applied as cathodes in batteries with Al foil anodes and commercial paper soaked in an electrolyte solution of NaCl.

Ropio, I, Baptista AC, Nobre J, Correia J, Belo F, Taborda S, Faustino MBM, Borges JB, Kovalenko A, Ferreira I.  2018.  Cellulose paper functionalised with polypyrrole and poly(3,4-ethylenedioxythiophene) for paper battery electrodes. Organic Electronics. 62:530-535. AbstractWebsite

A simple process of commercial paper functionalisation via in situ polymerisation of conductive polymers onto cellulose fibres was investigated and applied as electrodes in paper-based batteries. The functionalisation involved polypyrrole (PPy) and Poly (3,4-ethylenedioxythiophene) (PEDOT) as conductive polymers with the process of functionalisation optimised for each polymer individually with respect to oxidant-to-monomer ratios and polymerisation times and temperature. Paper with conductivity values of 44 mS/cm was obtained by exposing the samples to pyrrole vapour for a period of 30 min at room temperature; however, polymerisation at temperatures of 40 °C lead to higher conductivity values to up 141 mS/cm. Consequently, functionalised PPy and PEDOT papers were applied as cathodes in batteries with Al foil anodes and commercial paper soaked in an electrolyte solution of NaCl.

Baptista, AC, Ropio I, Romba B, Nobre J, Henriques C, Silva JC, Martins JI, Borges JP, Ferreira I.  2018.  Cellulose-based electrospun fibers functionalized with polypyrrole and polyaniline for fully organic batteries. Journal of Materials Chemistry A. 6(1):256-265. AbstractWebsite

A novel cellulose-based bio-battery made of electrospun fibers activated by biological fluids has been developed. This work reports a new concept for a fully organic bio-battery that takes advantage of the high surface to volume ratio achieved by an electrospun matrix composed of sub-micrometric fibers that acts simultaneously as the separator and the support of the electrodes. Polymer composites of polypyrrole (PPy) and polyaniline (PANI) with cellulose acetate (CA) electrospun matrix were produced by in situ chemical oxidation of pyrrole and aniline on the CA fibers. The structure (CA/PPy|CA|CA/PANI) generated a power density of 1.7 mW g−1 in the presence of simulated biological fluids, which is a new and significant contribution to the domain of medical batteries and fully organic devices for biomedical applications.

Baptista, AC, Ropio I, Romba B, Nobre JP, Henriques C, Silva JC, Martins JI, Borges JP, Ferreira I.  2018.  Cellulose-based electrospun fibers functionalized with polypyrrole and polyaniline for fully organic batteries. J Mater Chem A. 6(1):256-265. AbstractWebsite

A novel cellulose-based bio-battery made of electrospun fibers activated by biological fluids has been developed. This work reports a new concept for a fully organic bio-battery that takes advantage of the high surface to volume ratio achieved by an electrospun matrix composed of sub-micrometric fibers that acts simultaneously as the separator and the support of the electrodes. Polymer composites of polypyrrole (PPy) and polyaniline (PANI) with cellulose acetate (CA) electrospun matrix were produced by in situ chemical oxidation of pyrrole and aniline on the CA fibers. The structure (CA/PPy|CA|CA/PANI) generated a power density of 1.7 mW g−1 in the presence of simulated biological fluids, which is a new and significant contribution to the domain of medical batteries and fully organic devices for biomedical applications.

Giannakidis, G, Gargiulo M, De Miglio R, Chiodi A, Seixas J, Simoes SG, Dias L, Gouveia J.  2018.  Challenges faced when addressing the role of cities towards a below 2-degree world. Limiting Global Warming to Well Below 2°C: Energy System Modelling and Policy Development. (Giannakidis G., K. Karlsson, M. Labriet, B. Ó Gallachóir, Eds.).: Lecture Notes in Energy 64. Springer International publishing. Doi: 10.1007/978-3-319-74424-7
Faustino, BMM, Gomes D, Faria J, Juntunen T, Gaspar G, Bianchi C, Almeida A, Marques AC, Tittonen I, Ferreira I.  2018.  CuI p-type thin films for highly transparent thermoelectric pn modules. Sci Rep. 8(1):6867-6867. AbstractWebsite

Developments in thermoelectric (TE) transparent p-type materials are scarce and do not follow the trend of the corresponding n-type materials – a limitation of the current transparent thermoelectric devices. P-type thermoelectric thin films of CuI have been developed by three different methods in order to maximise optical transparency (>70% in the visible range), electrical (σ = 1.1 × 104 Sm−1) and thermoelectric properties (ZT = 0.22 at 300 K). These have been applied in the first planar fully transparent p-n type TE modules where gallium-doped zinc oxide (GZO) thin films were used as the n-type element and indium thin oxide (ITO) thin films as electrodes. A thorough study of power output in single elements and p-n modules electrically connected in series and thermally connected in parallel is inclosed. This configuration allows for a whole range of highly transparent thermoelectric applications.

Samhan-Arias, AK, Fortalezas S, Cordas C, Moura I, Moura JJG, Gutierrez-Merino C.  2018.  Cytochrome b5 reductase is the component from neuronal synaptic plasma membrane vesicles that generates superoxide anion upon stimulation by cytochrome c. Redox Biol. 15:109-114.
Pádua, AC, Palma S, Gruber J, Gamboa H, Roque ACA.  2018.  Design and Evolution of an Opto-electronic Device for VOCs Detection. Proceedings of the 11th International Joint Conference on Biomedical Engineering Systems and Technologies. :48-55. AbstractPDFWebsite

Electronic noses (E-noses) are devices capable of detecting and identifying Volatile Organic Compounds (VOCs) in a simple and fast method. In this work, we present the development process of an opto-electronic device based on sensing films that have unique stimuli-responsive properties, altering their optical and electrical properties, when interacting with VOCs. This interaction results in optical and electrical signals that can be collected, and further processed and analysed. Two versions of the device were designed and assembled. E-nose V1 is an optical device, and E-nose V2 is a hybrid opto-electronic device. Both E-noses architectures include a delivery system, a detection chamber, and a transduction system. After the validation of the E-nose V1 prototype, the E-nose V2 was implemented, resulting in an easy-to-handle, miniaturized and stable device. Results from E-nose V2 indicated optical signals reproducibility, and the possibility of coupling the electrical signals to the opt ical response for VOCs sensing.

Rebocho, S, Cordas CM, Viveiros R, Casimiro T.  2018.  Development of a ferrocenyl-based MIP in supercritical carbon dioxide: Towards an electrochemical sensor for bisphenol A. J Supercrit Fluids. 135:98-104.Website
Giancristofaro, A, Barbosa AJM, Ammazzalorso A, Amoia P, Filippis BD, Fantacuzzi M, Giampietro L, Maccallinia C, Amoroso R.  2018.  Discovery of new FXR agonists based on 6-ECDCA binding properties by virtual screening and molecular docking. MedChemComm. (9):1630-1638.Website
Mirante, F, Dias L, Silva M, Ribeiro SO, Corvo MC, de Castro B, Granadeiro CM, Balula SS.  2018.  Efficient heterogeneous polyoxometalate-hybrid catalysts for the oxidative desulfurization of fuels. Catalysis Communications. 104:1–8.: Elsevier AbstractWebsite

The heterogenization of the highly active monovacant polyoxotungstate ([PW11O39]7 −, abbreviated as PW11) was achieved by preparing the corresponding long chain quaternary ammonium salt (ODA7PW11, ODA = CH3(CH2)17(CH3)3N). The complete cation exchange confers total heterogeneity to the monovacant catalyst while keeping its oxidative catalytic activity. In fact, the heterogeneous catalyst allowed for the complete desulfurization of a multicomponent model diesel (2000 ppm S) after 40 min of reaction, conciliating extraction (using BMIMPF6 solvent) and oxidation (ECODS process using H2O2 oxidant). The heterogeneous catalyst has shown a superior desulfurization performance when compared with the homogeneous quaternary ammonium TBAPW11 catalyst (TBA = (C4H9)4 N). Both hybrid catalysts have been successfully reused in consecutive ECODS cycles. Additionally, the long carbon chain cations provide a protective environment around the polyoxometalate allowing for ODA7PW11 to retain its heterogeneity and structure after the ECODS process.

Matos, R, Chaparro C, Silva JC, Valente M, Borges JP, Soares PIP.  2018.  Electrospun composite cellulose acetate/iron oxide nanoparticles non-woven membranes for magnetic hyperthermia applications. Carbohydrate polymers. 198:9-16. AbstractWebsite

In the present work composite membranes were produced by combining magnetic nanoparticles (NPs) with cellulose acetate (CA) membranes for magnetic hyperthermia applications. The non-woven CA membranes were produced by electrospinning technique, and magnetic NPs were incorporated by adsorption at fibers surface or by addition to the electrospinning solution. Therefore, different designs of composite membranes were obtained. Superparamagnetic NPs synthesized by chemical precipitation were stabilized either with oleic acid (OA) or dimercaptosuccinic acid (DMSA) to obtain stable suspensions at physiological pH. The incorporation of magnetic NP into CA matrix was confirmed by scanning and transmission electron microscopy. The results showed that adsorption of magnetic NPs at fibers’ surface originates composite membranes with higher heating ability than those produced by incorporation of magnetic NPs inside the fibers. However, adsorption of magnetic NPs at fibers’ surface can cause cytotoxicity depending on the NPs concentration. Tensile tests demonstrated a reinforcement effect caused by the incorporation of magnetic NPs in the non-woven membrane.

Fernandes, CSM, Teixeira GDG, Iranzo O, Roque ACA.  2018.  Engineered protein variants for bioconjugation. Biomedical Applications of Functionalized Nanomaterials - Concepts, Development and Clinical Translation. (Sarmento, Bruno, Jose Das Neves, Eds.).: Elsevier
Surra, E, Bernardo M, Lapa N, Esteves IAAC, Fonseca I, Mota JP.  2018.  Enhanced Biogas Production through Anaerobic co-Digestion of OFMSW with Maize Cob Waste Pre-Treated with Hydrogen Peroxide. Chemical Engineering Transactions. 65:121-126.
Sousa, DM, Cerqueira L, Marques A, Gaspar G, Lima JC, Ferreira I.  2018.  Facile Microwave-assisted Synthesis Manganese Doped Zinc Sulfide Nanoparticles. Scientific Reports. 8:15992.