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2021
Lopes, R, Raya-Barón Á, Robalo PM, Vinagreiro C, Barroso S, Romão MJ, Fernández I, Pereira MM, Royo B.  2021.  Donor Functionalized Iron(II) N-Heterocyclic Carbene Complexes in Transfer Hydrogenation Reactions. European Journal of Inorganic Chemistry. 2021:22-29., Number 1 AbstractWebsite

Two piano-stool iron(II) complexes bearing N-heterocyclic carbene ligands outfitted with acetamide- and amine-pendant arms [Cp*Fe(NHCR)(CO)I] {Cp* = η5-tetramethylcyclopentadienyl; R = CH2CONEt2 (3), (CH2)2NEt2 (4)}, have been prepared and fully characterized. Their catalytic activity in transfer hydrogenation (TH) of ketones using iPrOH as a hydrogen source and catalytic amounts of base (LiOtBu) has been explored, along with that of previously reported [CpFe(NHCR)(CO)I] {R = nBu (5), (CH2)2OH (6), Et (7), and (CH2)3OH (8)} complexes containing hydroxyl and nonfunctionalized alkyl arms. Complex 3 displayed the highest catalytic activity of the whole series 3–8, reaching a TOF50 value of 533 h–1. NMR monitoring of the stoichiometric reaction of 3 with LiOtBu, allowed the identification of a new species 3' containing a deprotonated amidate moiety, which has been fully characterized by 1H, 13C, and 15N NMR. Finally, a green protocol for the reduction of ketones through TH using glycerol as a hydrogen source, under microwave irradiation in the presence of catalytic amounts of 3 and base has been developed.

Duarte, M, Viegas A, Alves VD, Prates JAM, Ferreira LMA, Najmudin S, Cabrita EJ, Carvalho AL, Fontes CMGA, Bule P.  2021.  A dual cohesin–dockerin complex binding mode in Bacteroides cellulosolvens contributes to the size and complexity of its cellulosome. Journal of Biological Chemistry. 296:100552. AbstractWebsite

The Cellulosome is an intricate macromolecular protein complex that centralizes the cellulolytic efforts of many anaerobic microorganisms through the promotion of enzyme synergy and protein stability. The assembly of numerous carbohydrate processing enzymes into a macromolecular multiprotein structure results from the interaction of enzyme-borne dockerin modules with repeated cohesin modules present in noncatalytic scaffold proteins, termed scaffoldins. Cohesin–dockerin (Coh-Doc) modules are typically classified into different types, depending on structural conformation and cellulosome role. Thus, type I Coh-Doc complexes are usually responsible for enzyme integration into the cellulosome, while type II Coh-Doc complexes tether the cellulosome to the bacterial wall. In contrast to other known cellulosomes, cohesin types from Bacteroides cellulosolvens, a cellulosome-producing bacterium capable of utilizing cellulose and cellobiose as carbon sources, are reversed for all scaffoldins, i.e., the type II cohesins are located on the enzyme-integrating primary scaffoldin, whereas the type I cohesins are located on the anchoring scaffoldins. It has been previously shown that type I B. cellulosolvens interactions possess a dual-binding mode that adds flexibility to scaffoldin assembly. Herein, we report the structural mechanism of enzyme recruitment into B. cellulosolvens cellulosome and the identification of the molecular determinants of its type II cohesin–dockerin interactions. The results indicate that, unlike other type II complexes, these possess a dual-binding mode of interaction, akin to type I complexes. Therefore, the plasticity of dual-binding mode interactions seems to play a pivotal role in the assembly of B. cellulosolvens cellulosome, which is consistent with its unmatched complexity and size.

2020
Strohmeier, P, Honnet C, Perner-Wilson H, Teyssier M, Fruchard B, Baptista AC, Steimle J.  2020.  Demo of PolySense: How to Make Electrically Functional Textiles. CHI Conference on Human Factors in Computing Systems. :1-4. Abstract

We demonstrate a simple and accessible method for enhancing textiles with custom piezo-resistive properties. Based on in-situ polymerization, our method offers seamless integration at the material level, preserving a textile's haptic and mechanical properties. We demonstrate how to enhance a wide set of fabrics and yarns using only readily available tools. During each demo session, conference attendees may bring textile samples which will be polymerized in a shared batch. Attendees may keep these samples. While the polymerization is happening, attendees can inspect pre-made samples and explore how these might be integrated in functional circuits. Examples objects created using polymerization include rapid manufacturing of on-body interfaces, tie-dyed motion-capture clothing, and zippers that act as potentiometers.

J.J.G., M.  2020.  Design of Artificial Enzymes Using the Metals of the Periodic Table. Memories of the Class of Sciences, Academia das Ciências de Lisboa.
Haque, S, Alexandre M, Mendes MJ, Águas H, Fortunato E, Martins R.  2020.  Design of wave-optical structured substrates for ultra-thin perovskite solar cells. Applied Materials Today. 20(100720)
dos Santos, LM, Bernard FL, Polesso BB, Pinto IS, Frankenberg CC, Corvo MC, Almeida PL, Cabrita E, Menezes S, Einloft S.  2020.  Designing silica xerogels containing RTIL for CO2 capture and CO2/CH4 separation: Influence of ILs anion, cation and cation side alkyl chain length and ramification. Journal of Environmental Management. 268:110340. AbstractWebsite

CO2 separation from natural gas is considered to be a crucial strategy to mitigate global warming problems, meet product specification, pipeline specs and other application specific requirements. Silica xerogels (SX) are considered to be potential materials for CO2 capture due to their high specific surface area. Thus, a series of silica xerogels functionalized with imidazolium, phosphonium, ammonium and pyridinium-based room-temperature ionic liquids (RTILs) were synthesized. The synthesized silica xerogels were characterized by NMR, helium pycnometry, DTA-TG, BET, SEM and TEM. CO2 sorption, reusability and CO2/CH4 selectivity were assessed by the pressure-decay technique. Silica xerogels containing IL demonstrated advantages compared to RTILs used as separation solvents in CO2 capture processes including higher CO2 sorption capacity and faster sorption/desorption. Using fluorinated anion for functionalization of silica xerogels leads to a higher affinity for CO2 over CH4. The best performance was obtained by SX- [bmim] [TF2N] (223.4 mg CO2/g mg/g at 298.15 K and 20 bar). Moreover, SX- [bmim] [TF2N] showed higher CO2 sorption capacity as compared to other reported sorbents. CO2 sorption and CO2/CH4 selectivity results were submitted to an analysis of variance and the means compared using Tukey's test (5%).

Maiti, BK, Moura JJG.  2020.  Diverse biological roles of the tetrathiomolybdate anion. Coord Chem Rev. 429:213635.
Rijo, B, Lemos F, Fonseca I, Vilelas A.  2020.  Development of a model for an industrial acetylene hydrogenation reactor using plant data – Part I. Chemical Engineering Journal. 379:122390. AbstractWebsite

In this work, a dynamic model of an industrial acetylene hydrogenation reactor with a front-end configuration was developed, based on plant operation data. This type of reactor operates in transient state, not only due to the natural fluctuations in operating conditions but also due to the effects caused by the deactivation of the catalyst. To develop the dynamic model of the acetylene hydrogenation reactor a thorough study of the effect of operating conditions was performed; the influence of variables such as the inlet temperature of the 1st reactor, the flowrate, carbon monoxide concentration, on the activity, selectivity and stability of the catalyst was examined by choosing adequate periods of the operation of the reactor. To understand the reaction mechanism of this system, several published kinetics were tested but only one was finally fitted to the industrial data, to interpret the operation of the acetylene hydrogenation reactor. A set of operation periods was used to develop the model which was then validated by applying the model to a different set of operation periods. As a conclusion, the dynamic model that was developed and validated, using actual plant operation data, was able to adequately describe the outlet temperatures of the three reactors in the system as well as the outlet acetylene concentration of the 3rd reactor.

2019
Collaço, F, Simoes SG, Dias L, Duic N, Seixas J, Bermann C.  2019.  The dawn of urban energy planning – synergies between energy and urban planning for São Paulo (Brazil) megacity. Journal of Cleaner Production. 215:458-479,doi:https://doi.org/10.1016/j.jclepro.2019.01.013.
dos Santos, R, Figueiredo C, Viecinski AC, Pina AS, Barbosa AJM, Roque ACA.  2019.  Designed affinity ligands to capture human serum albumin. Journal of Chromatography A. 1583:88-97. AbstractWebsite

Human serum albumin (HSA) in an important therapeutic agent and disease biomarker, with an increasing market demand. By proteins and drugs that bind to HSA as inspiration, a combinatorial library of 64 triazine-based ligands was rationally designed and screened for HSA binding at physiological conditions. Two triazine-based lead ligands (A3A2 and A6A5), presenting more than 50% HSA bound and high enrichment factors, were selected for further studies. Binding and elution conditions for HSA purification from human plasma were optimized for both ligands. The A6A5 adsorbent yielded a purified HSA sample with 98% purity at 100% recovery yield under mild binding and elution conditions.

Fernandes, TM, Morgado L, Salgueiro CA, Turner DL.  2019.  Determination of the magnetic properties and orientation of the heme axial ligands of PpcA from G. metallireducens by paramagnetic NMR. Journal of Inorganic Biochemistry. 198:110718. AbstractWebsite

The rising interest in the use of Geobacter bacteria for biotechnological applications demands a deep understanding of how these bacteria are able to thrive in a variety of environments and perform extracellular electron transfer. The Geobacter metallireducens bacterium can couple the oxidation of a wide range of compounds to the reduction of several extracellular acceptors, including heavy metals, toxic organic compounds or electrode surfaces. The periplasmic c-type cytochrome PpcA from this bacterium is a member of a family composed of five periplasmic triheme cytochromes, which are important to bridge the electron transfer between the cytoplasm and the extracellular environment. To better understand the functional mechanism of PpcA it is essential to obtain structural data for this cytochrome. In this work, the geometry of the heme axial ligands, as well as the magnetic properties of the hemes were determined for the oxidized form of the cytochrome, using the 13C NMR chemical shifts of the heme α-substituents. The results were further compared with those previously obtained for the homologous cytochrome from Geobacter sulfurreducens. The orientations of the axial histidine planes and the magnetic properties of the hemes are conserved in both proteins. Overall, the results obtained allowed the definition of the orientation of the magnetic axes of PpcA from G. metallireducens, which will be used as constraints to assist the solution structure determination of the cytochrome in the oxidized form.

Raminhos, J, Borges JB, Velhinho A.  2019.  Development of polymeric anepectic meshes: auxetic metamaterials with negative thermal expansion. Smart Materials and Structures. 28(4):045010. AbstractWebsite

his paper reports the application of additive manufacturing technology to fabricate bi-dimensional lightweight composite meshes capable of demonstrating auxetic properties (negative Poisson's ratio (NPR)) in combination with negative thermal expansion (NTE) behaviour, using as constituent materials polymers that do not exhibit NTE behaviour. To describe the combination of NPR and NTE characteristics, the designation of 'anepectic' is being proposed. Each mesh, obtained from varying either the material combination or the design parameters, was tested on a heated silicone bath to study the effects of the different combinations on the coefficient of thermal expansion (CTE). It was found that all meshes studied demonstrated a successful combination of NPR and NTE behaviours, and it was revealed that there is a possibility to tailor the meshes to activate the NTE behaviour within a chosen range of temperatures. For an extreme case, a Poisson's ratio of −0.056, along with a CTE of −1568 × 10−6 K−1 has been achieved.

Cordas, CM, Campaniço M, Baptista R, Maia L, Moura I, Moura JJG.  2019.  Direct electrochemical reduction of carbon dioxide by a molybdenum-containing formate dehydrogenase. J Inorg Biochem. 196:110694.Website
2018
Vinhas, R, Louren{\c c}o A, Santos S, Ribeiro P, Silva M, {de Sousa} {AB}, Baptista {PV}, Fernandes {AR}.  2018.  A double Philadelphia chromosome-positive chronic myeloid leukemia patient, co-expressing P210BCR-ABL1 and P195BCR-ABL1 isoforms, nov. Haematologica. 103:e549–e552., Number 11: Ferrata Storti Foundation Abstract
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Sequeira, A, Lourenco A, Ferreira LM, Branco PS, Mendes Z, Lourenco NMT, Figueiredo M, Carvalho LCR.  2018.  A Different Approach to the EGFR Inhibitor Gefitinib Involving Solid-Phase Synthesis, JUN. SYNLETT. 29:1346-1350., Number 10 Abstract
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Vinhas, R, Lourenco A, Santos S, Ribeiro P, Silva M, de Sousa AB, Baptista PV, Fernandes AR.  2018.  A double Philadelphia chromosome-positive chronic myeloid leukemia patient, co-expressing P210(BCR-ABL1) and P195(BCR-ABL1) isoforms, 2018. Haematologica. 103(11):e549-e552. AbstractWebsite
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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
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. The Journal of Supercritical Fluids. 135:98-104. AbstractWebsite
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Marcelo, G, Ferreira IC, Viveiros R, Casimiro T.  2018.  Development of itaconic acid-based molecular imprinted polymers using supercritical fluid technology for pH-triggered drug delivery. International Journal of Pharmaceutics. 542:125-131., Number 1 AbstractWebsite
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2017
Coelho, {BJ}, Veigas B, Águas H, Fortunato E, Martins R, Baptista {PV}, Igreja R.  2017.  A digital microfluidics platform for loop-mediated isothermal amplification detection, nov. Sensors. 17, Number 11: MDPI - Multidisciplinary Digital Publishing Institute Abstract

Digital microfluidics (DMF) arises as the next step in the fast-evolving field of operation platforms for molecular diagnostics. Moreover, isothermal schemes, such as loop-mediated isothermal amplification (LAMP), allow for further simplification of amplification protocols. Integrating DMF with LAMP will be at the core of a new generation of detection devices for effective molecular diagnostics at point-of-care (POC), providing simple, fast, and automated nucleic acid amplification with exceptional integration capabilities. Here, we demonstrate for the first time the role of coupling DMF and LAMP, in a dedicated device that allows straightforward mixing of LAMP reagents and target DNA, as well as optimum temperature control (reaction droplets undergo a temperature variation of just 0.3°C, for 65°C at the bottom plate). This device is produced using low-temperature and low-cost production processes, adaptable to disposable and flexible substrates. DMF-LAMP is performed with enhanced sensitivity without compromising reaction efficacy or losing reliability and efficiency, by LAMP-amplifying 0.5 ng/µL of target DNA in just 45 min. Moreover, on-chip LAMP was performed in 1.5 µL, a considerably lower volume than standard bench-top reactions.

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.

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