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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.

Araújo, N, Fernandes C, Moniz AB, Barata J.  2017.  Additive technology safety issues: Impact on the related job design in industry, 7-8 Sep. 2017. 4º Congresso Internacional sobre Condições de Trabalho. , Porto: Rede de Investigação sobre Condições de Trabalho (RICOT) Abstract

The embedding of technology and the digitalization of processes and services within industry holds the promise for increased flexibility and productivity. Associated with the tendencies within industry 4.0 there are several enabling technologies, such has 3D printing and additive manufacturing technologies that are becoming very popular and used for industrial processes, although not without hazard. With the present paper the authors aim to explore the impacts industrial 3D printing on health and safety at work and design possible industrial intervention measures.
The technological process underneath 3D printing by itself encompasses hazardous exposure scenarios, for example: i) those that imply that thermoplastics are heated, nozzle extruded and then deposited onto a surface to build a part. Thus, by-product nanoparticles (< 1/10.000 of a millimetre) are emitted; ii) for low temperature polylactic acid (PLA) 20 billion of particles per minute can be released; iii) at higher temperatures acrylonitrile butadiene styrene (ABS) feedstock can release up to 200 billion nanoparticles.
The raw materials, can have multiple uses (e.g. raw material or support materials), origins (e.g. metallic, plastic) and forms (e.g. solid, powder). These materials encompass hazards related with: i) harmful chemicals, used mainly on support materials that are used to allow the creation of empty spaces on printed parts, such as phenyl phosphates, hazardous during use and disposal; ii) the use of metal powders, such as titanium and aluminium can spontaneously combust causing fires; iii) hot surfaces, high voltage, ultraviolet radiation, laser and moving parts are important hazards related with 3D printing machines.
Occupational health and safety measures must deal with: 1. technology that allows the contention of the hazardous agent emission without compromising the production process – for example by airtight chambers, ventilation and exhaustion chambers; 2. Compliance with ATEX directives, for metal powders use; 3. development of training and certification requirements for operating 3D industrial processes and to capacitate workers (materials, techniques, best practises); 4. Making available protective equipment’s that respond to the hazards.
There are many practical challenges related with occupational health and safety, for 3D printing technologies industrial incorporation and ownership. It’s known that hazardous materials are released during the fabrication processes, although the exposure scenarios are not well known or studied. More robust experiments and sophisticated control methods are needed to know and tackle the hazards for 3Dprinting use in industrial contexts – the size and distribution of particles (including nanoparticles), its concentration, its mass and the total volatile organic compound (COV). The study of Huang et al (2013) on societal impact develops these issues.
Since the product safety regulations depend currently on centralized manufacturing (safety testing and regular inspection in factories), 3D printing is expected to bring a dispersion of manufacturing, raising questions about safety issues. Some authors suggests that even if we move the regulation process from the products to the software of the manufacturing process in 3D-printing, concerns still remain due to the poor success of the information regulation on line as well as to the scarce ability to stop the distribution of files, particularly when combined with jurisdictional concerns.

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.

Bule, P, Alves VD, Israeli-Ruimy V, Carvalho AL, Ferreira LMA, Smith SP, Gilbert HJ, Najmudin S, Bayer EA, Fontes CMGA.  2017.  Assembly of Ruminococcus flavefaciens cellulosome revealed by structures of two cohesin-dockerin complexes, 2017. Scientific Reports. 7:759. AbstractWebsite

Cellulosomes are sophisticated multi-enzymatic nanomachines produced by anaerobes to effectively deconstruct plant structural carbohydrates. Cellulosome assembly involves the binding of enzyme-borne dockerins (Doc) to repeated cohesin (Coh) modules located in a non-catalytic scaffoldin. Docs appended to cellulosomal enzymes generally present two similar Coh-binding interfaces supporting a dual-binding mode, which may confer increased positional adjustment of the different complex components. Ruminococcus flavefaciens’ cellulosome is assembled from a repertoire of 223 Doc-containing proteins classified into 6 groups. Recent studies revealed that Docs of groups 3 and 6 are recruited to the cellulosome via a single-binding mode mechanism with an adaptor scaffoldin. To investigate the extent to which the single-binding mode contributes to the assembly of R. flavefaciens cellulosome, the structures of two group 1 Docs bound to Cohs of primary (ScaA) and adaptor (ScaB) scaffoldins were solved. The data revealed that group 1 Docs display a conserved mechanism of Coh recognition involving a single-binding mode. Therefore, in contrast to all cellulosomes described to date, the assembly of R. flavefaciens cellulosome involves single but not dual-binding mode Docs. Thus, this work reveals a novel mechanism of cellulosome assembly and challenges the ubiquitous implication of the dual-binding mode in the acquisition of cellulosome flexibility.

Mendoza, J, Basilio N, Dangles O, Mora N, Al Bittar S, Pina F.  2017.  Binding of the five multistate species of the anthocyanin analog 7-beta-D-glucopyranosyloxy-4'-hydroxyflavylium to the beta-cyclodextrin derivative captisol, 2017. Dyes and Pigments. 143:479-487. 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.  Cellulose Nanocrystals: Mind the Microgap in Iridescent Cellulose Nanocrystal Films (Adv. Mater. 2/2017), 2017. Advanced MaterialsAdvanced Materials. 29(2): John Wiley & Sons, Ltd AbstractWebsite

Cellulose nanocrystals are isolated from plant cellulose structures, e.g., cotton. In article 1603560, M. H. Godinho and co-workers describe a tunable photonic material produced from these cellulose nanocrystals iridescent films, which reflects both right- and left-handed circularly polarized light, taking advantage of the gaps existing along the cellulose nanocrystals films that are filled with a nematic liquid crystal.

Huang, RJ, Avo J, Northey T, Chaning-Pearce E, dos Santos PL, Ward JS, Data P, Etherington MK, Fox MA, Penfold TJ, Berberan-Santos MN, Lima JC, Bryce MR, Dias FB.  2017.  The contributions of molecular vibrations and higher triplet levels to the intersystem crossing mechanism in metal-free organic emitters, 2017. Journal of Materials Chemistry C. 5(25):6269-6280. 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.

Aguilo, E, Soler L, Casanovas A, Moro AJ, Lima JC, Rodriguez L, Llorca J.  2017.  Gold(I)-Complex-Titania Hybrid Photocatalyst for Hydrogen Production, 2017. Chemcatchem. 9(17):3289-3292. AbstractWebsite
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do Nascimento-Neto, LG, Cabral MG, Carneiro RF, Silva Z, Arruda FVS, Nagano CS, Fernandes AR, Sampaio AH, and Videira* EHT* PA.  2017.  Halilectin-3, a Lectin from the Marine Sponge Haliclona caerulea, Induces Apoptosis and Autophagy in Human Breast Cancer MCF7 Cells Through Caspase-9 Pathway and LC3-II Protein Expression, 2017. (Formerly Current Medicinal Chemistry - Anti-Cancer Agents). 17:1-8. Abstract

Background: An ideal strategy for cancer treatment is the specific induction of tumor cell death, sparing normal cells. Marine sponges are rich biological reservoirs of biomolecules, especially lectins, which have attracted considerable attention due to potential biological effect on human cells. Lectins are proteins that bind specific carbohydrate signatures and some gained further interest for their capacity to bind tumor associated carbohydrates antigens and induce tumor cell apoptosis. Objective: This study aimed to evaluate the antitumor potential of H3, a lectin, recently reported from marine sponge Haliclona caerulea on the human breast cancer cell line MCF7. Results: H3 reduced MCF7 cell viability with an IC50 of 100 μg/ml, without a significant effect on normal cells. At 24h, H3 induced a significant arrest in the G1 cell cycle phase. Consistently, almost 50% of the cells were in early apoptosis and showed remarkable increased expression of caspase-9 (CASP 9). H3 impaired dramatically the adhesiveness of MCF7 cells in culture. Assays conducted with Lysotracker Red probe showed increased organelle acidity, suggesting autophagic cell death, which was further supported by increased expression of microtubule-associated protein light chain 3 (LC3) and observable conversion of LC3-I in LC3-II by western blot. Conclusion: The apoptotic effect of H3 may be related to a balance between apoptotic and autophagic cell death, mediated by increased expression of CASP 9 and LC3-II. To the best of our knowledge this is the first report about a sponge lectin triggering both apoptosis and autophagy in MCF7 cell.

Oliveira, J, Araujo P, Fernandes A, Bras NF, Mateus N, Pina F, de Freitas V.  2017.  Influence of the structural features of amino-based pyranoanthocyanins on their acid-base equilibria in aqueous solutions, 2017. Dyes and Pigments. 141:479-486. AbstractWebsite
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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.

Romero, MA, Basilio N, Moro AJ, Domingues M, Gonzalez-Delgado JA, Arteaga JF, Pischel U.  2017.  Photocaged Competitor Guests: A General Approach Toward Light-Activated Cargo Release From Cucurbiturils, 2017. Chemistry-a European Journal. 23(53):13105-13111. AbstractWebsite
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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, 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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Simoes, SG, Halstead M, Selosse S, Assoumou E.  2017.  Enhancement of the ETSAP E-Techs Database with water consumption and withdrawal data, 13 December. ETSAP Workshop on modelling the water-energy nexus. , Zurich, Switzerland: ETH Zurich
Beira, MJ, Daniel CI, Almeida PL, Corvo MC, Rosatella AA, Afonso CAM, Sebastiao PJ.  2017.  1H NMR Relaxometry and Diffusometry Study of Magnetic and Non-Magnetic Ionic Liquid-Based Solutions: Co-Solvent and Temperature Effects. The Journal of Physical Chemistry B. : ACS Publications AbstractWebsite

In this work, 1H NMR relaxometry and diffusometry as well as viscometry experiments were carried out as a means to study the molecular dynamics of magnetic and non-magnetic ionic liquid-based systems. In order to evaluate the effect of a co-solvent on the super-paramagnetic properties observed for Aliquat-iron-based magnetic ionic liquids, mixtures comprising different concentrations, 1% and 10% (v/v), of DMSO-d6 were prepared and analyzed. The results suggest that, when at low concentrations, DMSO-d6 promotes more structured ionic arrangements, thus enhancing these super-paramagnetic properties. Furthermore, the analysis of temperature and water concentration effects allowed to conclude that neither one of these variables sufficiently affected the super-paramagnetic properties of the studied magnetic ionic liquids.

Sanchez-Sobrado, O, et al.  2017.  Colloidal-lithographed TiO2 photonic nanostructures for solar cell light trapping. J. Mater. Chem. C. 5:6852-6861.
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.

Almeida, RM, Dell'Acqua S, Moura I, Pauleta SR, Moura JJG.  2017.  Electron transfer and molecular recognition in denitrification and nitrate dissimilatory pathways. Metalloenzymes in Denitrification: Applications and Environmental Impacts, RSC Metallobiology Series No. 9 (ISBN: 978-1-78262-376-2).. (Moura, I., Moura, J. J. G., Pauleta, S. R., Maia, L. B., Eds.).:252-286.: Royal Society of Chemistry
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