@article {INOCENCIO2021110541, title = {Ibuprofen incorporated into unmodified and modified mesoporous silica: From matrix synthesis to drug release}, journal = {Microporous and Mesoporous Materials}, volume = {310}, year = {2021}, note = {n/a}, pages = {110541}, abstract = {

Aiming to rationalize the release profile of an incorporated pharmaceutical drug in terms of its mobility, driven by guest-host interactions, the poorly water-soluble ibuprofen drug was loaded in a mesoporous inorganic silica matrix with unmodified (MCM-41) and modified surface (MCM-41sil) by post-synthesis silylation, both having pore sizes~~~3~nm. The single calorimetric detection of a broad glass transition step for both ibuprofen composites indicates full drug amorphization, confirmed by the only appearance of an amorphous halo in the powder XRD patterns. Moreover, a gradient profile is disclosed by the heat flux derivative plot in the glass transition, in coherence with the thermogravimetric profile that shows a multi-step decomposition trace for confined ibuprofen in these matrixes. While identical guest dynamics, as probed by dielectric relaxation spectroscopy, were found in both dehydrated composites, a significant molecular population with faster relaxation exists in the hydrated state for the drug inside the unmodified matrix. This was rationalized as the concurrence of true confinement effects, which manifest under nanometer dimensions, and greater water affinity of the unmodified matrix, forcing the drug molecules to be placed mostly in the pore core. Finite size effects are also felt in both dehydrated composites, however guest-host interactions give origin to a dominant population with slowed down mobility that governs the overall guest dynamics. In spite of an inferior number of active sites for drug adsorption in the silylated matrix, a faster ibuprofen delivery in phosphate buffer (pH~=~6.8) was observed when the drug is released from unmodified MCM-41 in the hydrated state. Therefore, our results suggest that a relevant role is played by water molecules, which impair a strong guest adsorption in the host surface more efficiently than the limited surface modification, influence the higher ratio of a faster population in the pore core and facilitate the diffusion of the aqueous releasing media inside pores.

}, keywords = {Amorphous materials, Confinement, Dielectric spectroscopy, Drug delivery, Magic angle spinning nuclear magnetic spectroscopy}, issn = {1387-1811}, doi = {https://doi.org/10.1016/j.micromeso.2020.110541}, url = {http://www.sciencedirect.com/science/article/pii/S1387181120305412}, author = {Sara Inoc{\^e}ncio and Cordeiro, Teresa and Matos, In{\^e}s and Florence Dan{\`e}de, and Sotomayor, Jo{\~a}o C. and Fonseca, Isabel M. and Nat{\'a}lia T. Correia and Corvo, Marta C. and Madalena Dion{\'\i}sio} } @article {GODINOOJER202064, title = {Acidic porous carbons involved in the green and selective synthesis of benzodiazepines}, journal = {Catalysis Today}, volume = {357}, year = {2020}, note = {

SI: CarboCat{\textendash}VIII

}, pages = {64 - 73}, abstract = {

Eco-sustainable and recyclable porous carbons are reported as metal-free catalysts for the synthesis of benzodiazepines for the first time. The porous carbons were able to efficiently catalyse the synthesis of benzodiazepine 1 from o-phenylendiamine 2 and acetone 3 under mild conditions. Both acidic functions and the porosity of the catalysts were determinant features. High conversion values were obtained when using HNO3 oxidized carbons. The highest selectivity to benzodiazepine 1 was obtained in the presence of the most microporous catalyst N-N, which is indicative of the great influence of porous properties. Stronger acid sites and high microporosity of the carbon treated with H2SO4 yield benzodiazepine 1 with total selectivity.

}, keywords = {activated carbons, benzodiazepines, Heterocyclic chemistry, Heterogeneous catalytic systems}, issn = {0920-5861}, doi = {https://doi.org/10.1016/j.cattod.2019.11.027}, url = {http://www.sciencedirect.com/science/article/pii/S0920586118312938}, author = {M. Godino-Ojer and Matos, I. and M. Bernardo and Carvalho, R. and Ol{\'\i}via Salom{\'e} {G.P. Soares} and C. Dur{\'a}n-Valle and I. M. Fonseca and E. P{\'e}rez Mayoral} } @article {10.7717/peerj.9488, title = {Assessment of potato peel and agro-forestry biochars supplementation on in vitro ruminal fermentation}, journal = {PeerJ}, volume = {8}, year = {2020}, note = {n/a}, pages = {e9488}, abstract = {

Background The awareness of environmental and socio-economic impacts caused by greenhouse gas emissions from the livestock sector leverages the adoption of strategies to counteract it. Feed supplements can play an important role in the reduction of the main greenhouse gas produced by ruminants{\textemdash}methane (CH\textsubscript{4}). In this context, this study aims to assess the effect of two biochar sources and inclusion levels on rumen fermentation parameters \textit{in vitro}. Methods Two sources of biochar (agro-forestry residues, AFB, and potato peel, PPB) were added at two levels (5 and 10\%, dry matter (DM) basis) to two basal substrates (haylage and corn silage) and incubated 24-h with rumen inocula to assess the effects on CH\textsubscript{4} production and main rumen fermentation parameters \textit{in vitro}. Results AFB and PPB were obtained at different carbonization conditions resulting in different apparent surface areas, ash content, pH at the point of zero charge (pHpzc), and elemental analysis. Relative to control (0\% biochar), biochar supplementation kept unaffected total gas production and yield (mL and mL/g DM, \textit{p}~=~0.140 and \textit{p}~=~0.240, respectively) and fermentation pH (\textit{p}~=~0.666), increased CH\textsubscript{4}production and yield (mL and mL/g DM, respectively, \textit{p}~=~0.001) and ammonia-N (NH\textsubscript{3}-N, \textit{p}~=~0.040), and decreased total volatile fatty acids (VFA) production (\textit{p}~\<~0.001) and H\textsubscript{2} generated and consumed (\textit{p}~<=~0.001). Biochar sources and inclusion levels had no negative effect on most of the fermentation parameters and efficiency. Acetic:propionic acid ratio (\textit{p}~=~0.048) and H\textsubscript{2} consumed (\textit{p}~=~0.019) were lower with AFB inclusion when compared to PPB. Biochar inclusion at 10\% reduced H\textsubscript{2} consumed (\textit{p}~\<~0.001) and tended to reduce total gas production (\textit{p}~=~0.055). Total VFA production (\textit{p}~=~0.019), acetic acid proportion (\textit{p}~=~0.011) and H\textsubscript{2} generated (\textit{p}~=~0.048) were the lowest with AFB supplemented at 10\%, no differences being observed among the other treatments. The basal substrate affected most fermentation parameters independently of biochar source and level used. Discussion Biochar supplementation increased NH\textsubscript{3}-N content, \textit{iso}-butyric, \textit{iso}-valeric and valeric acid proportions, and decreased VFA production suggesting a reduced energy supply for microbial growth, higher proteolysis and deamination of substrate N, and a decrease of NH\textsubscript{3}-N incorporation into microbial protein. No interaction was found between substrate and biochar source or level on any of the parameters measured. Although AFB and PPB had different textural and compositional characteristics, their effects on the rumen fermentation parameters were similar, the only observed effects being due to AFB included at 10\%. Biochar supplementation promoted CH\textsubscript{4} production regardless of the source and inclusion level, suggesting that there may be other effects beyond biomass and temperature of production of biochar, highlighting the need to consider other characteristics to better identify the mechanism by which biochar may influence CH\textsubscript{4} production.

}, keywords = {Agro-forestry biochar, Enteric methane, Potato peel biochar, Rumen fermentation, Supplementation level}, issn = {2167-8359}, doi = {10.7717/peerj.9488}, url = {https://doi.org/10.7717/peerj.9488}, author = {Rodrigues, Ana R.F. and Maia, Margarida R.G. and Cabrita, Ana R.J. and Oliveira, Hugo M. and Bernardo, Maria and Nuno Lapa and Fonseca, Isabel and Trindade, Henrique and Pereira, Jos{\'e} L. and Fonseca, Ant{\'o}nio J.M.} } @article {CORDEIRO2020121973, title = {Biocompatible locust bean gum as mesoporous carriers for naproxen delivery}, journal = {Materials Chemistry and Physics}, volume = {239}, year = {2020}, note = {n/a}, pages = {121973}, abstract = {

The work reports the impregnation of naproxen into locust bean gum mesoporous matrixes with different textural properties. The matrixes were prepared through the dissolution of the biopolymer in water and in two ionic liquids (ILs): [bmim][Cl] and [C2OHmim][Cl] and dried with scCO2. The poor water-soluble pharmaceutical drug naproxen was loaded into the matrixes and the composites were characterized by attenuated total reflectance-Fourier transform infrared spectroscopy and by differential scanning calorimetry; the results were compared with neat ILs and drug. The naproxen release from the matrixes was attempted at pH 7.4. Sustained release of naproxen in the different composites occurs, and consequently the naproxen release has lower rates compared with neat crystalline naproxen dissolution. Nevertheless, it was possible to observe small differences on release profiles for the studied composites. The higher release rate was observed for the composite where [bmim][Cl] was used as solvent, for which the calorimetric analysis revealed full amorphization of the incorporated drug. Cytotoxicity assays reveal that cellular viability in Caco-2 cells is preserved. This fact allied with the biocompatibility of locust bean gum allow for the composites potential application as naproxen controlled/sustained delivery systems with higher drug bioavailability achieved through naproxen amorphization.

}, keywords = {Amorphous state, Drug loading, Drug release, DSC, Locust bean gum mesoporous matrixes}, issn = {0254-0584}, doi = {https://doi.org/10.1016/j.matchemphys.2019.121973}, url = {http://www.sciencedirect.com/science/article/pii/S0254058419307722}, author = {Cordeiro, Teresa and Ana B. Paninho and Bernardo, Maria and Matos, In{\^e}s and Carolina V. Pereira and Ana Teresa Serra and Matias, Ana and M{\'a}rcia G. Ventura} } @article {CASTANHEIRO202076, title = {Glycerol conversion into biofuel additives by acetalization with pentanal over heteropolyacids immobilized on zeolites}, journal = {Catalysis Today}, volume = {346}, year = {2020}, note = {

The Green Catalytic Processes Special Issue on the 6th International Congress on Green Process Engineering

}, pages = {76 - 80}, abstract = {

Dodecamolydbophosphoric acid (HPMo) immobilized on USY zeolite was used as a catalyst for the acetalization of glycerol with pentanal at 70 {\textdegree}C. Catalysts were prepared with different amounts of heteropolyacid, and the most active sample was the HPMo2@Y catalyst (1.1 wt.\%). The products of glycerol acetalization with pentanal were (2-butyl-1,3-dioxolan-4-yl)methanol, a five-member ring compound, and 2-butyl-1,3-dioxan-5-ol, a six-member ring compound. Good values of selectivity for the five-member ring compound (80{\textendash}85\%) were obtained with all materials. The reaction conditions were optimized using HPMo2@Y as a catalyst. The optimal conditions were determined to be 70 {\textdegree}C reaction temperature with 0.3 g catalyst and a 1:2.5 M ratio of glycerol to pentanal. The catalytic stability of HPMo2@Y was studied. The acetalization of glycerol with pentanal was performed using the same sample. High catalytic activity for HPMo2@Y was observed.

}, keywords = {Acetalization, Glycerol, Green processes, Heterogeneous catalysis, Heteropolyacids}, issn = {0920-5861}, doi = {https://doi.org/10.1016/j.cattod.2019.04.048}, url = {http://www.sciencedirect.com/science/article/pii/S0920586118312409}, author = {Castanheiro, J. E. and Vital, J. and I. M. Fonseca and A. M. Ramos} } @article {BERNARDO2020170, title = {Porous carbons derived from hydrothermally treated biogas digestate}, journal = {Waste Management}, volume = {105}, year = {2020}, note = {n/a}, pages = {170 - 179}, abstract = {

Porous carbons from digestate-derived hydrochar were produced, characterized and their performance to reclaim phosphate from water was evaluated as a preliminary approach to demonstrate their practical application. In a first step, the digestate was converted into hydrochars through hydrothermal carbonization by using two different pH conditions: 8.3 (native conditions) and 3.0 (addition of H2SO4). The resulting hydrochars did not present significant differences. Consecutively, the hydrochars were activated with KOH to produce activated carbons with enhanced textural properties. The resulting porous carbons presented marked differences: the AC native presented a lower ash content (20.3~wt\%) and a higher surface area (SBET~=~1106~m2/g) when compared with the AC-H2SO4 (ash content~=~43.7~wt\% SBET~=~503~m2/g). Phosphorus, as phosphate, is a resource present in significative amount in wastewater, causing serious problems of eutrophication. Therefore, the performance of the porous carbons samples to recover phosphate {\textendash} P(PO43-) {\textendash} from water was evaluated through exploitation assays that included kinetic studies. The lumped model presented a good fitting to the kinetic data and the obtained uptake capacities were the same for both carbons, 12~mg P(PO43-)/g carbon. Despite the poorer textural properties of AC-H2SO4, this carbon was richer in Ca, Al, Fe, K, and Mg cations which promoted the formation of mineral complexes with phosphate anions. The results obtained in this work are promising for the future development of P(PO43-) enriched carbons that can be used thereafter as biofertilizers in soil amendment applications.

}, keywords = {Biogas production, Biomass digestate, Hydrothermal carbonization, Nanoporous carbons, Phosphate recovery from water}, issn = {0956-053X}, doi = {https://doi.org/10.1016/j.wasman.2020.02.011}, url = {http://www.sciencedirect.com/science/article/pii/S0956053X20300696}, author = {Bernardo, Maria and Catalina Rodriguez Correa and Yvonne Ringelspacher and Gero C. Becker and Nuno Lapa and Fonseca, Isabel and Isabel A.A.C. Esteves and Andrea Kruse} } @article {AGOSTINHO2020123290, title = {Properties of κ-carrageenan aerogels prepared by using different dissolution media and its application as drug delivery systems}, journal = {Materials Chemistry and Physics}, volume = {253}, year = {2020}, note = {n/a}, pages = {123290}, abstract = {

This work reports the synthesis of kappa-carrageenan aerogels using different dissolution and crosslinking media in order to evaluate its effects on the textural properties of the matrixes and further on the drug loading and release performance. The different aerogel samples were produced through the dissolution of the biopolymer in water with addition of potassium salts as crosslinking agents and, in two different ionic liquids (ILs) derived from imidazolium ion, being further dried with supercritical CO2. The samples were characterized by Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR), Scanning Electron Microscopy (SEM), Nitrogen Adsorption-Desorption Analysis, Thermogravimetry (TGA) and Differential Scanning Calorimetry (DSC). The synthesized samples presented surface areas similar to the carrageenan aerogels being their structure constituted mainly by meso and macropores. The absence of ionic liquid in samples was demonstrated by DSC analysis and was corroborated by the cytotoxicity assays which revealed that cellular viability in Caco-2~cells was preserved. Tetracycline was used as a model drug and loaded in two of the prepared aerogels samples. The release experiments were performed with the composites to test in vitro drug release at physiologic pH. With a higher macroporosity, the kappa-carrageenan aerogel prepared by dissolution into ionic liquid showed a higher loading capacity than the one prepared by dissolution into water and a slightly higher release rate. The matrixes were considered to present a good potential to be used as biocompatible carriers on drug controlled delivery.

}, keywords = {biocompatibility, Drug release, Kappa-carrageenan aerogels, Tetracycline}, issn = {0254-0584}, doi = {https://doi.org/10.1016/j.matchemphys.2020.123290}, url = {http://www.sciencedirect.com/science/article/pii/S025405842030660X}, author = {Daniela A.S. Agostinho and Paninho, Ana I. and Cordeiro, Teresa and Nunes, Ana V. M. and Fonseca, Isabel M. and Carolina Pereira and Matias, Ana and M{\'a}rcia G. Ventura} } @article {FERNANDES2019121973, title = {Evaluation of the adsorption potential of biochars prepared from forest and agri-food wastes for the removal of fluoxetine}, journal = {Bioresource Technology}, volume = {292}, year = {2019}, note = {n/a}, pages = {121973}, abstract = {

Twelve biochars from forest and agri-food wastes (pruning of Quercus ilex, Eucalyptus grandis, Pinus pinaster, Quercus suber, Malus pumila, Prunus spinosa, Cydonia oblonga, Eriobotrya japonica, Juglans regia, Actinidia deliciosa, Citrus sinensis and Vitis vinifera) were investigated as potential low-cost and renewable adsorbents for removal of a commonly used pharmaceutical, fluoxetine. Preliminary adsorption experiments allowed to select the most promising adsorbents, Quercus ilex, Cydonia oblonga, Eucalyptus, Juglans regia and Vitis vinifera pruning material. They were characterized by proximate, elemental and mineral analysis, thermogravimetric analysis, Fourier transform infrared spectroscopy, determination of specific surface area and pH at the point of zero charge. Batch and equilibrium studies were performed, and the influence of pH was evaluated. The equilibrium was reached in less than 15 min in all systems. The maximum adsorption capacity obtained was 6.41 mg/g for the Eucalyptus biochar, which also demonstrated a good behavior in continuous mode (packed column).

}, keywords = {Anti-depressant pharmaceutical, Biochar, Column experiments, Kinetics and equilibrium, Waste valorization}, issn = {0960-8524}, doi = {https://doi.org/10.1016/j.biortech.2019.121973}, url = {http://www.sciencedirect.com/science/article/pii/S0960852419312039}, author = {Maria Jo{\~a}o Fernandes and Manuela M. Moreira and Paula Pa{\'\i}ga and Diogo Dias and Bernardo, Maria and Manuela Carvalho and Nuno Lapa and Fonseca, Isabel and Simone Morais and S{\'o}nia Figueiredo and Cristina Delerue-Matos} } @article {CASTANHEIRO2019, title = {Glycerol conversion into biofuel additives by acetalization with pentanal over heteropolyacids immobilized on zeolites}, journal = {Catalysis Today}, year = {2019}, note = {n/a}, abstract = {

Dodecamolydbophosphoric acid (HPMo) immobilized on USY zeolite was used as a catalyst for the acetalization of glycerol with pentanal at 70 {\textdegree}C. Catalysts were prepared with different amounts of heteropolyacid, and the most active sample was the HPMo2@Y catalyst (1.1 wt.\%). The products of glycerol acetalization with pentanal were (2-butyl-1,3-dioxolan-4-yl)methanol, a five-member ring compound, and 2-butyl-1,3-dioxan-5-ol, a six-member ring compound. Good values of selectivity for the five-member ring compound (80{\textendash}85\%) were obtained with all materials. The reaction conditions were optimized using HPMo2@Y as a catalyst. The optimal conditions were determined to be 70 {\textdegree}C reaction temperature with 0.3 g catalyst and a 1:2.5 M ratio of glycerol to pentanal. The catalytic stability of HPMo2@Y was studied. The acetalization of glycerol with pentanal was performed using the same sample. High catalytic activity for HPMo2@Y was observed.

}, keywords = {Acetalization, Glycerol, Green processes, Heterogeneous catalysis, Heteropolyacids}, issn = {0920-5861}, doi = {https://doi.org/10.1016/j.cattod.2019.04.048}, url = {http://www.sciencedirect.com/science/article/pii/S0920586118312409}, author = {Castanheiro, J. E. and Vital, J. and I. M. Fonseca and A. M. Ramos} } @article {Bernardo2017, title = {Study of the removal mechanism of aquatic emergent pollutants by new bio-based chars}, journal = {Environmental Science and Pollution Research}, volume = {24}, number = {28}, year = {2017}, note = {n/a}, month = {Oct}, pages = {22698{\textendash}22708}, abstract = {

This work is dedicated to study the potential application of char byproducts obtained in the gasification of rice husk (RG char) and rice husk blended with corn cob (RCG char) as removal agents of two emergent aquatic contaminants: tetracycline and caffeine. The chars presented high ash contents (59.5{\textendash}81.5{\%}), being their mineral content mainly composed of silicon (as silica) and potassium. The samples presented a strong basic character, which was related to its higher mineral oxides content. RCG char presented better textural properties with a higher apparent surface area (144~m2~g-1) and higher micropore content (V micro~=~0.05~cm3~g-1). The alkaline character of both chars promoted high ecotoxicity levels on their aqueous eluates; however, the ecotoxic behaviour was eliminated after pH correction. Adsorption experiments showed that RG char presented higher uptake capacity for both tetracycline (12.9~mg~g-1) and caffeine (8.0~mg~g-1), indicating that textural properties did not play a major role in the adsorption process. For tetracycline, the underlying adsorption mechanism was complexation or ion exchange reactions with the mineral elements of chars. The higher affinity of RG char to caffeine was associated with the higher alkaline character presented by this char.

}, issn = {1614-7499}, doi = {10.1007/s11356-017-9938-9}, url = {https://doi.org/10.1007/s11356-017-9938-9}, author = {Bernardo, Maria Manuel Serrano and Madeira, Catarina Alexandra Catanas and dos Santos Nunes, Nuno Carlos Lapa and Dias, Diogo Andr{\'e} Costa Messias and Godinho, Delfina Maria Barbosa and de Jesus Pinto, Maria Filomena and do Nascimento Matos, In{\^e}s Alexandra Morgado and Carvalho, Ana Paula Batista and de Figueiredo Ligeiro Fonseca, Isabel Maria} } @article {RODRIGUEZCORREA2017461, title = {Evaluation of hydrothermal carbonization as a preliminary step for the production of functional materials from biogas digestate}, journal = {Journal of Analytical and Applied Pyrolysis}, volume = {124}, year = {2017}, note = {n/a}, pages = {461 - 474}, abstract = {

Digestate from a biogas plant that uses solely biomass for biogas production was used as precursor material for the production of activated carbon as an alternative to increase its added value. The digestate was converted into hydrochar by hydrothermal carbonization varying the temperature (190{\textendash}250{\textdegree}C), residence time (3 and 6h), and pH (5 and 7). Temperature followed by residence time had the strongest influence on the chemical composition and thermal stability of the hydrochars. A significant effect of the pH was not observed. The hydrochars were chemically activated to enhance the surface area and use them as activated carbon. As a consequence, the surface areas increased from 8 to 14m2/g (hydrochars) to 930{\textendash}1351m2/g (activated carbons). Furthermore, large micropore volumes were measured (0.35{\textendash}0.50cm3/g). The activated carbons were studied as adsorbents in gas phase applications, showing that the product of digestate is a very effective adsorbent for carbon dioxide (CO2). Especially the activated carbon obtained from the hydrochar produced at 250{\textdegree}C for 6h, which adsorbed 8.80mol CO2/kg at 30{\textdegree}C and 14.8bar. Additionally, the activated carbons showed a stronger affinity towards CO2 compared to methane (CH4), which makes this material suitable for the upgrading of raw biogas to biomethane.

}, keywords = {Biogas, Carbon adsorbent materials, Digestate, Gas separation by adsorption, Hydrothermal carbonization}, issn = {0165-2370}, doi = {https://doi.org/10.1016/j.jaap.2017.02.014}, url = {http://www.sciencedirect.com/science/article/pii/S0165237016307586}, author = {Catalina Rodriguez Correa and Bernardo, Maria and Rui P.P.L. Ribeiro and Isabel A.A.C. Esteves and Andrea Kruse} } @article {CONCEICAO2017203, title = {Photochemical insights of TiO2 decorated mesoporous SBA-15 materials and their influence on the photodegradation of organic contaminants}, journal = {Microporous and Mesoporous Materials}, volume = {253}, year = {2017}, note = {n/a}, pages = {203 - 214}, abstract = {

Mesoporous silica, SBA-15, decorated with different amounts of TiO2 (anatase) were prepared by a sol-gel method followed by hydrothermal treatment and calcination, in the presence of a soft template, copolymer Pluronic 123. Tetraethyl orthosilicate (TEOS) was used as the SiO2 precursor and commercially available TiO2 anatase nanoparticles as the supported photocatalyst. The materials were characterized by transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDS), N2 adsorption-desorption isotherms, raman spectroscopy, ground state diffuse reflectance (GSDR), laser induced luminescence (LIL) and X-ray photoelectron spectroscopy (XPS). The zeta potentials of the pure SBA-15, TiO2/SBA-15 substrate and the commercial anatase sample were monitored through a complete range of pH values. All the nanomaterials developed in this work were studied in terms of their photoactivity in the UV range and in the visible range, separately. In the first case, hydroxyl radicals (OH) were confirmed to be the key active oxidizers in the photodegradation of the pesticide amicarbazone in aqueous medium. On the other hand, in the visible range, and following a dye sensitization process via a fluorescent rhodamine-like dye, two different mechanisms could be identified for the formation of the superoxide radical anion, O2-.

}, keywords = {Fluorescent dye, Mesoporous silica nanoparticles, Photocatalysis, Photochemistry, Titanium dioxide}, issn = {1387-1811}, doi = {https://doi.org/10.1016/j.micromeso.2017.07.013}, url = {http://www.sciencedirect.com/science/article/pii/S1387181117304857}, author = {D.S. Concei{\c c}{\~a}o and C.A.L. Gra{\c c}a and D.P. Ferreira and A.M. Ferraria and I. M. Fonseca and A.M. Botelho do Rego and A.C.S.C. Teixeira and Ferreira, L. F. Vieira} } @article {doi:10.1021/acs.molpharmaceut.7b00386, title = {Stabilizing Unstable Amorphous Menthol through Inclusion in Mesoporous Silica Hosts}, journal = {Molecular Pharmaceutics}, volume = {14}, number = {9}, year = {2017}, note = {

PMID: 28836790

}, pages = {3164-3177}, abstract = {n/a}, doi = {10.1021/acs.molpharmaceut.7b00386}, url = {https://doi.org/10.1021/acs.molpharmaceut.7b00386}, author = {Cordeiro, Teresa and Casti{\~n}eira, Carmem and Mendes, Davide and Florence Dan{\`e}de, and Jo{\~a}o Sotomayor and Fonseca, Isabel M. and Gomes da Silva, Marco and Alexandre Paiva and Barreiros, Susana and Cardoso, M Margarida and Viciosa, Maria T. and Nat{\'a}lia T. Correia and Dionisio, Madalena} } @article {CASTANHEIRO201716, title = {Tungstophosphoric acid immobilised in SBA-15 as an efficient heterogeneous acid catalyst for the conversion of terpenes and free fatty acids}, journal = {Microporous and Mesoporous Materials}, volume = {249}, year = {2017}, note = {n/a}, pages = {16 - 24}, abstract = {

Alkoxylation of α-pinene, β-pinene and limonene was performed in the presence of SBA-15-occluded tungstophosphoric acid (HPW). The HPW was immobilised in SBA-15 using the sol-gel method. The catalysts were characterised by N2 adsorption, FT-IR, Raman spectroscopy, X-Ray diffraction, ICP-AES and TEM. A series of catalysts with different heteropolyacid loadings ranging from 1.8 to 19.3~wt. \% were prepared. PW4-SBA-15 (with 10.8~wt. \%) exhibited the highest catalytic activity for the alkoxylation of α-pinene with ethanol. An approximately 53\% selectivity to α-terpinyl ethyl ether was observed over the PW-SBA-15 catalysts. PW4-SBA-15 was also used as a catalyst for the alkoxylation of other terpenes, including β-pinene and limonene. The PW4-SBA-15 catalyst exhibited high catalytic stability for the alkoxylation of α-pinene with ethanol. PW4-SBA-15 was also used as a catalyst for the esterification of free fatty acids (i.e., palmitic, stearic and oleic acids) with ethanol. Good catalytic activity was observed for the PW4-SBA-15 catalyst with the different substrates used in the esterifications.

}, keywords = {Fatty acids, Heteropolyacids, SBA-15, Terpenes}, issn = {1387-1811}, doi = {https://doi.org/10.1016/j.micromeso.2017.04.047}, url = {http://www.sciencedirect.com/science/article/pii/S1387181117302962}, author = {Castanheiro, J. E. and I. M. Fonseca and A. M. Ramos and Vital, J.} } @article {LOURENCO20171099, title = {Using a bacterial fucose-rich polysaccharide as encapsulation material of bioactive compounds}, journal = {International Journal of Biological Macromolecules}, volume = {104}, year = {2017}, note = {n/a}, pages = {1099 - 1106}, abstract = {

The potential of a bacterial exopolysaccharide named FucoPol, produced by the bacterium Enterobacter A47, as encapsulation matrix was explored. Spherical capsules with a smooth surface were produced by spray drying. The obtained microcapsules had average diameters ranging from 0.5 to 26.7μm and presented thin walls (thickness from 222 to 1094nm). The capsules were loaded with two bioactive compounds: gallic acid (GA) and oregano essential oil (OEO). Both bioactive materials were encapsulated in FucoPol particles, retaining their antioxidant activity after the drying process. Release studies showed that GA release in simulated gastric and intestinal fluids was faster than that of OEO, envisaging that the latter had established stronger interactions with the polymer matrix. These results suggest that FucoPol has a good potential for use as encapsulating material of bioactive compounds for application in several areas, including food, cosmetic or pharmaceutical products.

}, keywords = {FucoPol, Gallic acid, Microencapsulation, Oregano essential oil, Spray drying}, issn = {0141-8130}, doi = {https://doi.org/10.1016/j.ijbiomac.2017.07.023}, url = {http://www.sciencedirect.com/science/article/pii/S0141813017305883}, author = {Sofia C. Louren{\c c}o and Torres, Cristiana A. V. and Nunes, Daniela and Paulo Duarte and Freitas, Filomena and Reis, Maria A M and Elvira Fortunato and Margarida Mold{\~a}o-Martins and Lu{\'\i}sa Beir{\~a}o da Costa and V{\'\i}tor D. Alves} } @article {Silva2016, title = {Enhancing the biodiesel manufacturing process by use of glycerin to produce hyacinth fragrance}, journal = {Clean Technologies and Environmental Policy}, volume = {18}, number = {5}, year = {2016}, note = {n/a}, month = {Jun}, pages = {1551{\textendash}1563}, abstract = {

Oxidized and sulfonated-activated carbons (AC) were tested in the catalytic conversion of glycerol by acetalization reactions. The solids were treated with concentrated nitric acid and/or fuming sulfuric acid (AC, AC-N, AC-S, and AC-NS). The presence of sulfur and an increase in the acidity of the solids demonstrate the suitability of the oxidation as well as the sulfonation process, especially in the sample treated with concentrated nitric acid and fuming sulfuric acid (AC-NS). The best catalyst for the reaction of glycerol acetalization with phenylacetaldehyde was AC-NS, with a phenylacetaldehyde conversion of 95~{\%} after 90~min at 383~K and selectivity of 88 and 12~{\%}, respectively, to dioxolane and dioxane. These products can be used as hyacinth fragrance flavoring compounds. Furthermore, a contribution of homogeneous catalysis in these systems was not identified. Thus, we identified a possibility of glycerol conversion, a biodiesel by-product, into value-added products by suitable catalysts produced from activated carbons.

}, issn = {1618-9558}, doi = {10.1007/s10098-016-1136-9}, url = {https://doi.org/10.1007/s10098-016-1136-9}, author = {Silva, Cau{\^e} A. C. and Figueiredo, Fl{\'a}via C. A. and Rodrigues, Raphael and Sairre, Mirela I. and Gon{\c c}alves, Maraisa and Matos, Ines and Fonseca, Isabel M. and Mandelli, Dalmo and Carvalho, Wagner A.} } @article {Bernardo2016, title = {High efficacy on diclofenac removal by activated carbon produced from potato peel waste}, journal = {International Journal of Environmental Science and Technology}, volume = {13}, number = {8}, year = {2016}, note = {n/a}, month = {Aug}, pages = {1989{\textendash}2000}, abstract = {

In the present study, a novel porous carbon obtained by K2CO3 activation of potato peel waste under optimized conditions was applied for the first time as liquid-phase adsorbent of sodium diclofenac in parallel with a commercial activated carbon. The biomass-activated carbon presented an apparent surface area of 866~m2~g-1 and well-developed microporous structure with a large amount of ultramicropores. The obtained carbon presented leaching and ecotoxicological properties compatible with its safe application to aqueous medium. Kinetic data of laboratory-made and commercial sample were best fitted by the pseudo-second-order model. The commercial carbon presented higher uptake of diclofenac, but the biomass carbon presented the higher adsorption rate which was associated with its higher hydrophilic nature which favoured external mass transfer. Both adsorbents presented adsorption isotherms that were best fitted by Langmuir model. The biomass carbon and the commercial carbon presented adsorption monolayer capacities of 69 and 146~mg~g-1, and Langmuir constants of 0.38 and 1.02~L~mg-1, respectively. The better performance of the commercial sample was related to its slightly higher micropore volume, but the most remarkable effect was the competition of water molecules in the biomass carbon.

}, issn = {1735-2630}, doi = {10.1007/s13762-016-1030-3}, url = {https://doi.org/10.1007/s13762-016-1030-3}, author = {M. Bernardo and Rodrigues, S. and N. Lapa and Matos, I. and F. Lemos and Batista, M. K. S. and Carvalho, A. P. and I. Fonseca} } @article {doi:10.1021/acs.jpcc.6b04078, title = {Accessing the Physical State and Molecular Mobility of Naproxen Confined to Nanoporous Silica Matrixes}, journal = {The Journal of Physical Chemistry C}, volume = {120}, number = {26}, year = {2016}, note = {n/a}, pages = {14390-14401}, abstract = {

The pharmaceutical drug naproxen was loaded in three different silica hosts with pore diameters of 2.4 (MCM), 3.2 (MCM), and 5.9 nm (SBA), respectively: napMCM\_2.4 nm, napMCM\_3.2 nm, and napSBA\_5.9 nm. To access the guest physical state in the prepared composites, differential scanning calorimetry (DSC), X-ray diffraction (XRD), and attenuated total reflectance Fourier transform infrared spectroscopy were used. The different techniques provided complementary information on a molecular population that was revealed to be distributed among different environments, namely the pore core, the inner pore wall, and the outer surface. It was found that naproxen is semicrystalline in the higher pore size matrix being able to crystallize inside pores; after melting it undergoes full amorphization. In the case of the lower pore size matrix, naproxen crystallizes outside pores due to an excess of filling while most of the remaining fraction is incorporated inside the pores as amorphous. Crystallinity in these two composites was observed by the emergence of the Bragg peaks in the XRD analysis, whereas for napMCM\_3.2 nm only the amorphous halo was detected. The latter only exhibits the step due to the glass transition by DSC remaining stable as amorphous at least for 12 months. The glass transition in the three composites is abnormally broad, shifting to higher temperatures as the pore size decreases, coherent with the slowing down of molecular mobility as probed by dielectric relaxation spectroscopy. For napSBA\_5.9 nm the dielectric response was deconvoluted in two processes: a hindered surface (S-) process due to molecules interacting with the inner pore wall and a faster α-relaxation associated with the dynamic glass transition due to molecules relaxing in the pore core, which seems a manifestation of true confinement effects. The drug incorporation inside a nanoporous matrix, mainly in 3.2 nm pores, was revealed to be a suitable strategy to stabilize the highly crystallizable drug naproxen in the amorphous/supercooled state and to control its release from the silica matrix, allowing full delivery after 90 min in basic media.

}, doi = {10.1021/acs.jpcc.6b04078}, url = {https://doi.org/10.1021/acs.jpcc.6b04078}, author = {Cordeiro, Teresa and Santos, Andreia F. M. and Nunes, Guilherme and Cunha, Guilherme and Sotomayor, Jo{\~a}o C. and Fonseca, Isabel M. and Florence Dan{\`e}de, and C. J. Dias and Cardoso, M Margarida and Nat{\'a}lia T. Correia and M. Teresa Viciosa and Madalena Dion{\'\i}sio} } @article {C6RA09006K, title = {Biodiesel production waste as promising biomass precursor of reusable activated carbons for caffeine removal}, journal = {RSC Adv.}, volume = {6}, year = {2016}, note = {n/a}, pages = {45419-45427}, publisher = {The Royal Society of Chemistry}, abstract = {

Biodiesel production generates low particle size rapeseed waste (recovered from warehouse air filtration systems) that was herein explored as promising biomass precursor of chemically activated carbons. The influence of several experimental parameters on the porosity development was investigated. No benefit was observed when solution impregnation was made nor a significant dependence of the biomass : K2CO3 ratio was observed and{,} as expected{,} high porosity development was obtained only for treatments at 700 [degree]C. Microporous materials with apparent surface area around 1000 m2 g-1 were obtained comparing favorably with literature data regarding activated carbons from rapeseed processing by-products. A selected lab-made sample and two commercial carbons were tested as adsorbents of caffeine from aqueous solution. Although commercial materials present a quicker adsorption rate{,} regarding adsorption capacity the lab-made sample reaches the same value attained by a benchmark material. The regeneration tests made over the rapeseed derived carbon through heat treatments at 600 [degree]C for 1 hour under N2 flow proved that at least two exhaustion-regeneration cycles can be made since the material retains a caffeine adsorption capacity similar to that of the fresh carbon. Therefore{,} a waste management problem of biodiesel industry - rapeseed residue - can be transformed in a valuable material with promising properties for environmental remediation processes.

}, doi = {10.1039/C6RA09006K}, url = {http://dx.doi.org/10.1039/C6RA09006K}, author = {Batista, Mary K. S. and Ana S. Mestre and Matos, Ines and Fonseca, Isabel M. and Ana P. Carvalho} } @inbook {Lyubchik2016, title = {The Kinetic Parameters Evaluation for the Adsorption Processes at {\textquoteleft}{\textquoteleft}Liquid{\textendash}Solid{\textquoteright}{\textquoteright} Interface}, booktitle = {Electrokinetics Across Disciplines and Continents: New Strategies for Sustainable Development}, year = {2016}, note = {n/a}, pages = {81{\textendash}109}, publisher = {Springer International Publishing}, organization = {Springer International Publishing}, address = {Cham}, abstract = {

The kinetic parameters of the adsorption process at {\textquoteleft}{\textquoteleft}liquid{\textendash}solid{\textquoteright}{\textquoteright} interface have been evaluated through the sets of time-based experiments of the Cr(III) adsorption under varying temperature, initial metal concentration, and carbon loading for two sets of the commercially available activated carbons and their post-oxidized forms with different texture and surface functionality.

}, isbn = {978-3-319-20179-5}, doi = {10.1007/978-3-319-20179-5_5}, url = {https://doi.org/10.1007/978-3-319-20179-5_5}, author = {Lyubchik, Svetlana and Lygina, Elena and Lyubchyk, Andriy and Lyubchik, Sergiy and Loureiro, Jos{\'e} M. and Fonseca, Isabel M. and Ribeiro, Alexandra B. and Pinto, Margarida M. and Figueiredo, Agnes M. S{\'a}}, editor = {Ribeiro, Alexandra B. and Mateus, Eduardo P. and Couto, Nazar{\'e}} }