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2017
Peixoto, D, Figueiredo M, Gawande MB, Corvo MC, Vanhoenacker G, Afonso CAM, Ferreira LM, Branco PS.  2017.  Developments in the Reactivity of 2-Methylimidazolium Salts, JUN 16. JOURNAL OF ORGANIC CHEMISTRY. 82:6232-6241., Number 12 Abstract
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Coelho, B, Veigas B, Fortunato E, Martins R, Águas H, Igreja R, Baptista {PV}.  2017.  Digital microfluidics for nucleic acid amplification, jul. Sensors. 17, Number 7: MDPI - Multidisciplinary Digital Publishing Institute Abstract

Digital Microfluidics (DMF) has emerged as a disruptive methodology for the control and manipulation of low volume droplets. In DMF, each droplet acts as a single reactor, which allows for extensive multiparallelization of biological and chemical reactions at a much smaller scale. DMF devices open entirely new and promising pathways for multiplex analysis and reaction occurring in a miniaturized format, thus allowing for healthcare decentralization from major laboratories to point-of-care with accurate, robust and inexpensive molecular diagnostics. Here, we shall focus on DMF platforms specifically designed for nucleic acid amplification, which is key for molecular diagnostics of several diseases and conditions, from pathogen identification to cancer mutations detection. Particular attention will be given to the device architecture, materials and nucleic acid amplification applications in validated settings.

Sulim, O, Ribeiro R, Esteves I, Antunes C, Garate A, Duarte P, Ferreira I, Mota J, Plaza M.  2017.  Design of structured adsorbents for aplications in gas adsorption processes - Conventional shaping vs 3D-Printed formulation, 5-10 March. Abstract

Microporous materials highly activated and with potential to be used as adsorbents in many applications for gas
separation/purification are usually available as powders. These solids usually have a great and reversible gas
uptake, high gas selectivity, good chemical and thermal stability, but are unsuitable to be used in gas adsorption
processes, such as Pressure Swing Adsorption (PSA) or Simulated Moving Bed (SMB).
Zeolites, carbons and more recently metal-organic frameworks (MOFs) are examples of those materials. Their
use in adsorption-based processes are dependent of their upgrading from powders (micrometer scale) to
particles (pellets, spheres or granules at millimeter scale). This would overcome large pressure drops and
consequent energy consumptions when packing adsorbent columns in those processes. Thus, shaping
adsorbents is an important step to use them in industry, although it greatly affects their capacity and selectivity
towards a specific gas separation.
In this work, we explore techniques to shape powdered adsorbents, followed by their textural and mechanical
characterizations, and the study of their adsorption properties towards the main components of post-combustion
flues gases (CO2 and N2). Materials densification is proposed by employing two approaches:
- Conventional shaping through binderless mechanical compression and binder-containing extrusion; and
- Formulation by 3D printing (or additive manufacturing) to produce packed bed morphologies that
precisely replicate computer aided design (CAD) models.
Porous separation media are important for fluid-solid contacting in many unit operations, including adsorption.
Due to practical limitations, media particles are typically packed randomly into a column in a shaped form,
allowing fluid to flow through the interstitial voids. Key to the effectiveness of packed columns are the flowrelated properties of mass transfer, fluid distribution and dispersion, and back pressure, which in turn depend
upon packing geometry. Until now, no alternative was found to overcome this limitation and have optimal
ordered packing arrangements at the micron scale. 3D-Printing (or additive manufacturing) brings a wide range
of benefits that traditional methods of manufacturing or prototyping simply cannot. With this approach, complex
ordered geometries, that are not possible by conventional extrusion, can be designed and printed for a porous
media, being the equipment resolution the only limiting step to overcome.
The effect of parameters like compression force, particle sieving, binder nature, binder/adsorbent ratio were
firstly studied using conventional shaping techniques, as a basis for the consequent development of 3D-printed
formulations. The structured samples are then characterized and adsorption equilibria studies are performed on
them to evaluate their performance as media for gas adsorption separation processes. A volumetric/manometric
adsorption unit built in-house was used for this purpose. Relevant experimental data is obtained, which allows to
conclude that 3D-printed media can be an alternative porous media for application in gas adsorption processes.

Cruz, H, Jordao N, Branco LC.  2017.  Deep eutectic solvents (DESs) as low-cost and green electrolytes for electrochromic devices, 2017. Green Chemistry. 19(7):1653-1658. AbstractWebsite
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Santoro, S, Sebastian V, Moro AJ, Portugal CAM, Lima JC, Coelhoso IM, Crespo JG, Mallada R.  2017.  Development of fluorescent thermoresponsive nanoparticles for temperature monitoring on membrane surfaces, 2017. Journal of Colloid and Interface Science. 486:144-152. AbstractWebsite
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Tavares, M, Cabral RP, Costa C, Martins P, Fernandes AR, Casimiro T, Aguiar-Ricardo A.  2017.  Development of PLGA dry powder microparticles by supercritical CO2-assisted spray-drying for potential vaccine delivery to the lungs, 2017. 128:235-243. AbstractWebsite

In this work, biocompatible and biodegradable poly(d-l-lactide-co-glycolide) (PLGA) composite microparticles with potential use as carrier for vaccines and other drugs to the lungs were developed using supercritical CO2-assisted spray-drying (SASD). Bovine serum albumin (BSA) was chosen as model vaccine, and l-leucine as a dispersibility enhancer, and their effects on the particle characteristics were evaluated. The dry powder formulations (DPFs) were characterized in terms of their morphology and aerodynamic performance using an in vitro aerosolization study – Andersen cascade impactor (ACI) − to obtain data such as the fine particle fraction (FPF) with percentages up to 43.4%, and the mass median aerodynamic diameter (MMAD) values between the 1.7 and 3.5μm. Additionally, pharmacokinetic and cytotoxicity studies were performed confirming that the produced particles have all the necessary requirements for potential pulmonary delivery.

Lenis-Rojas, OA, Roma-Rodrigues C, Fernandes AR, Marques F, Pérez-Fernández D, Guerra-Varela J, Sánchez L, Vázquez-García D, López-Torres M, Fernández A, Fernández JJ.  2017.  Dinuclear RuII(bipy)2 Derivatives: Structural, Biological, and in Vivo Zebrafish Toxicity Evaluation, 2017. Inorganic ChemistryInorganic Chemistry. 56(12):7127-7144.: American Chemical Society AbstractWebsite

Ruthenium-based drugs exhibit interesting properties as potential anticancer pharmaceuticals. We herein present the synthesis and characterization of a new family of ruthenium complexes with formulas [{Ru(bipy)2}2(μ-L)][CF3SO3]4 (L = bptz, 1a) and [{Ru(bipy)2}2(μ-L)][CF3SO3]2 (L = arphos, 2a; dppb, 3a; dppf, 4a), which were synthesized from the Ru(II) precursor compound cis-Ru(bipy)2Cl2. The complexes were characterized by elemental analysis, mass spectrometry, 1H and 31P{1H} NMR, IR spectroscopy, and conductivity measurements. The molecular structures for three Ru(II) compounds were determined by single-crystal X-ray diffraction. The newly developed compounds interact with CT-DNA by intercalation, in particular, 2a, 3a, and 4a, which also seemed to induce some extent of DNA degradation. This effect seemed to be related with the formation of reactive oxygen species. The cytotoxic activity was evaluated against A2780, MCF7, and MDAMB231 human tumor cells. Compounds 2a and 4a were the most cytotoxic with activity compared to cisplatin (∼2 μM, 72 h) in the A2780 cisplatin sensitive cells. All the compounds induced A2780 cell death by apoptosis, however, to a lesser extent for compounds 4a and 2a. For these compounds, the mechanism of cell death in addition to apoptosis seemed to involve autophagy. In vivo toxicity was evaluated using the zebrafish embryo model. LC50 estimates varied from 5.397 (3a) to 39.404 (1a) mg/L. Considering the in vivo toxicity in zebrafish embryos and the in vitro cytotoxicity in cancer cells, compound 1a seems to be the safest having no effect on dechirionation and presenting a good antiproliferative activity against ovarian carcinoma cells.Ruthenium-based drugs exhibit interesting properties as potential anticancer pharmaceuticals. We herein present the synthesis and characterization of a new family of ruthenium complexes with formulas [{Ru(bipy)2}2(μ-L)][CF3SO3]4 (L = bptz, 1a) and [{Ru(bipy)2}2(μ-L)][CF3SO3]2 (L = arphos, 2a; dppb, 3a; dppf, 4a), which were synthesized from the Ru(II) precursor compound cis-Ru(bipy)2Cl2. The complexes were characterized by elemental analysis, mass spectrometry, 1H and 31P{1H} NMR, IR spectroscopy, and conductivity measurements. The molecular structures for three Ru(II) compounds were determined by single-crystal X-ray diffraction. The newly developed compounds interact with CT-DNA by intercalation, in particular, 2a, 3a, and 4a, which also seemed to induce some extent of DNA degradation. This effect seemed to be related with the formation of reactive oxygen species. The cytotoxic activity was evaluated against A2780, MCF7, and MDAMB231 human tumor cells. Compounds 2a and 4a were the most cytotoxic with activity compared to cisplatin (∼2 μM, 72 h) in the A2780 cisplatin sensitive cells. All the compounds induced A2780 cell death by apoptosis, however, to a lesser extent for compounds 4a and 2a. For these compounds, the mechanism of cell death in addition to apoptosis seemed to involve autophagy. In vivo toxicity was evaluated using the zebrafish embryo model. LC50 estimates varied from 5.397 (3a) to 39.404 (1a) mg/L. Considering the in vivo toxicity in zebrafish embryos and the in vitro cytotoxicity in cancer cells, compound 1a seems to be the safest having no effect on dechirionation and presenting a good antiproliferative activity against ovarian carcinoma cells.

Gouveia, JP, Seixas J, Mestre A.  2017.  Daily Electricity Profiles from Smart Meters - Proxies of Active Behaviour for Space Heating and Cooling. Energy. 141:108-122. AbstractWebsite

Daily electricity consumption profiles from smart meters are explored as proxies of active behavior regarding space heating and cooling. The influence of the environment air temperature (multiple maximum and minimum daily thresholds) on electricity consumption was explored for a final sample of 19 households located in southwestern Europe (characterized by hot, dry summers and cool, wet winters), taking the full year of 2014. Statistical analysis of the deviations from hourly average electricity consumptions for each temperature thresholds was performed for each household. Firstly, these deviations could act as proxies highlighting possible lack of thermal comfort on space cooling, and partially on space heating, supported by door-to-door survey data, on socio-economic details of occupants, buildings bearing structure and equipment's ownership and use. Secondly, meaningful differences of consumers' behavior on electricity consumption pattern were identified as a response for space heating and cooling to the environment air temperatures thresholds. Additionally, statistical clusters of active and non-active behavior groups of households were assessed, showing the electricity use for space heating. This paper illustrates the importance of the widespread use of smart-meters data on the increasingly electrified buildings sector, to understand whether and how thermal comfort could be achieved through active climatization behavior of its occupants. This is particularly important in regions where automatic HVAC systems are almost absent.

Cruz, H, Jordão N, Amorim P, Dionísio M, Branco LC.  2017.  Deep Eutectic Solvents as Suitable Electrolytes for Electrochromic Devices. ACS Sustainable Chemistry and Engineering. 6(2):2240-2249.Website
Ribeiro, SO, Nogueira LS, Gago S, Almeida PL, Corvo MC, de Castro B, Granadeiro CM, Balula SS.  2017.  Desulfurization Process conciliating Heterogeneous Oxidation and liquid extraction: Organic Solvent or Centrifugation/Water? Applied Catalysis A: General. : Elsevier AbstractWebsite

The present work presents a strategic oxidative desulfurization system able to efficiently operate under sustainable conditions, i.e. using an eco-friendly oxidant and without the need of extractive organic solvents. The catalytic performance of Eu(PW11O39)2@aptesSBA-15 was evaluated for the oxidative desulfurization of a multicomponent model diesel using a solvent-free or biphasic systems. The results reveal its remarkable desulfurization performance achieving complete desulfurization after just 2 h of reaction. Moreover, the composite has shown a high recycling ability without loss of catalytic activity for ten consecutive ODS cycles. Interestingly, under solvent-free conditions it was possible to maintain the desulfurization efficiency of the biphasic system while being able to avoid the use of harmful organic solvents. In this case, a successful extraction of oxidized sulfur compounds was found conciliating centrifugation and water as extraction solvent. Therefore, this work reports an important step towards the development of novel eco-sustainable desulfurization systems with high industrial interest.

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.

Viveiros, R, Karim K, Piletsky SA, Heggie W, Casimiro T.  2017.  Development of a molecularly imprinted polymer for a pharmaceutical impurity in supercritical CO2: Rational design using computational approach. Journal of Cleaner Production. 168:1025-1031. AbstractWebsite
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Peixoto, D, Figueiredo M, Gawande MB, Corvo MC, Vanhoenacker G, Afonso CAM, Ferreira LM, Branco PS.  2017.  Developments in the Reactivity of 2-Methylimidazolium Salts. The Journal of organic chemistry. 82:6232–6241., Number 12: American Chemical Society Abstract
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2016
Brás, JLA, Pinheiro BA, Cameron K, Cuskin F, Viegas A, Najmudin S, Bule P, Pires VMR, Romão MJ, Bayer EA, Spencer HL, Smith S, Gilbert HJ, Alves VD, Carvalho AL, Fontes CMGA.  2016.  Diverse specificity of cellulosome attachment to the bacterial cell surface, dec. Scientific Reports. 6:38292.: The Author(s) AbstractWebsite

During the course of evolution, the cellulosome, one of Nature's most intricate multi-enzyme complexes, has been continuously fine-tuned to efficiently deconstruct recalcitrant carbohydrates. To facilitate the uptake of released sugars, anaerobic bacteria use highly ordered protein-protein interactions to recruit these nanomachines to the cell surface. Dockerin modules located within a non-catalytic macromolecular scaffold, whose primary role is to assemble cellulosomal enzymatic subunits, bind cohesin modules of cell envelope proteins, thereby anchoring the cellulosome onto the bacterial cell. Here we have elucidated the unique molecular mechanisms used by anaerobic bacteria for cellulosome cellular attachment. The structure and biochemical analysis of five cohesin-dockerin complexes revealed that cell surface dockerins contain two cohesin-binding interfaces, which can present different or identical specificities. In contrast to the current static model, we propose that dockerins utilize multivalent modes of cohesin recognition to recruit cellulosomes to the cell surface, a mechanism that maximises substrate access while facilitating complex assembly.

Gouveia, JP, Seixas J, Mestre A.  2016.  Daily Electricity Profiles from Smart Meters - Proxies of Active Behaviour for Space Heating and Cooling, 8-9 September. BEHAVE 4th European Conference on Behaviour and Energy Efficiency. , Coimbra, Portugal
Santoro, S, Moro AJ, Portugal CAM, Crespo JG, Coelhoso IM, Lima JC.  2016.  Development of oxygen and temperature sensitive membranes using molecular probes as ratiometric sensor, 2016. Journal of Membrane Science. 514:467-475. AbstractWebsite
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Basilio, N, Pischel U.  2016.  Drug Delivery by Controlling a Supramolecular Host-Guest Assembly with a Reversible Photoswitch, 2016. Chemistry-a European Journal. 22(43):15208-15211. AbstractWebsite
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Mendes, MJ, Araújo A, Vicente A, Águas H, Ferreira I, Fortunato E, Martins R.  2016.  Design of optimized wave-optical spheroidal nanostructures for photonic-enhanced solar cells. Nano Energy. 26:286-296. AbstractWebsite

The interaction of light with wavelength-sized photonic nanostructures is highly promising for light management applied to thin-film photovoltaics. Several light trapping effects come into play in the wave optics regime of such structures that crucially depend on the parameters of the photonic and absorbing elements. Thus, multi-parameter optimizations employing exact numerical models, as performed in this work, are essential to determine the maximum photocurrent enhancement that can be produced in solar cells.

Generalized spheroidal geometries and high-index dielectric materials are considered here to model the design of the optical elements providing broadband absorption enhancement in planar silicon solar cells. The physical mechanisms responsible for such enhancement are schematized in a spectral diagram, providing a deeper understanding of the advantageous characteristics of the optimized geometries. The best structures, composed of TiO2 half-spheroids patterned on the cells' top surface, yield two times higher photocurrent (up to 32.5 mA/cm2 in 1.5 µm thick silicon layer) than the same devices without photonic schemes.

These results set the state-of-the-art closer to the theoretical Lambertian limit. In addition, the considered light trapping designs are not affected by the traditional compromise between absorption enhancement versus current degradation by recombination, which is a key technological advantage.

Santos, TG, Miranda RM, Vieira TM, Farinha RA, Ferreira TJ, Quintino L, Vilaça P, de Carvalho CCCR.  2016.  Developments in micro- and nano-defects detection using bacterial cells. NDT & E International. 78:20-28. AbstractWebsite

This paper describes improvements to the Nondestructive Testing (NDT) technique recently proposed, based on the use of bacterial cell suspensions to identify micro- and nano-surface defects. New bacterial strains were used with magnetic fields to improve bacteria mobility. Different materials and defect morphologies were tested, including nanoindentation defects, micro-powder injection moulding components and micro-laser welding. Nanoindentations with 0.6 µm depth and 5.3 µm side length were successfully detected. Bacterial cells allow identifying different topographic attributes of the surfaces, such as roughness. Cracks of about 0.5 µm wide and 10 µm depth in a reference test block Type 1 were successfully detected.

Aroso, IM, Silva JC, Mano F, Ferreira ASD, Dionísio M, Sá-Nogueira I, Barreiros S, Reis RL, Paiva A, Duarte ARC.  2016.  Dissolution enhancement of active pharmaceutical ingredients by therapeutic deep eutectic systems. European Journal of Pharmaceutics and Biopharmaceutics. 98:57-66.Website
2015
Larguinho, M, Santos S, Almeida J, Baptista P.  2015.  DNA adduct identification using gold-aptamer nanoprobes, apr. Iet Nanobiotechnology. 9:95–101., Number 2: INST ENGINEERING TECHNOLOGY-IET Abstract

The optical and physico-chemical properties of gold nanoparticles (AuNPs) have prompted new and improved approaches which have greatly evolved the fields of biosensing and molecular detection. In this study, the authors took advantage of AuNPs' ease of modification and functionalised it with selected DNA aptamers using a salt aging method to produce gold-aptamer nanoprobes. After characterisation, these nanoprobes were subsequently used for biomolecular detection of glycidamide (GA)-guanine (Gua) adducts generated in vitro. The results are based on differences in nanoprobe stabilisation against salt-induced aggregation, similar to the non-cross-linking method developed by Baptista for discrimination of specific sequences. Alkylated Guas were efficiently discriminated from deoxyguanosine and GA in solution. Despite this, a clear identification of DNA adducts derived from genomic DNA alkylation has proven to be a more challenging task.

Viciosa, MT, Santos G, Costa A, Danede F, Branco LC, Jordao N, Correia NT, Dionisio M.  2015.  Dipolar motions and ionic conduction in an ibuprofen derived ionic liquid, 2015. Physical Chemistry Chemical Physics. 17(37):24108-24120. AbstractWebsite
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Stampar, SN, Morandini AC, Branco LC, da Silveira FL, Migotto AE.  2015.  Drifting in the oceans: Isarachnanthus nocturnus (Cnidaria, Ceriantharia, Arachnactidae), an anthozoan with an extended planktonic stage, 2015. Marine Biology. 162(11):2161-2169. AbstractWebsite
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Boavida, NFFG.  2015.  Decisions of Technology Innovation: The Role of Indicators. Universidade Nova de Lisboa. (António Brandão Moniz, Manuel Laranja, Eds.)., Lisbon: Universidade Nova de Lisboaphd_thesis_final_4.pdf