Synthesis, Bioavailability, and Cytotoxicity Studies

Funding Information: This work was supported by Portuguese funds from FCT/MCTES through the Associate Laboratory for Green Chemistry—LAQV (UIDB/50006/2020 and UIDP/50006/2020) and the project numbers PTDC/QUI-QOR/32406/2017 and PTDC/EAM-AMB/2023/2021. Ana R. Jesus and Ana Rita C. Duarte acknowledge the European Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation Programme, under grant agreement No ERC-2016-CoG 725034. Publisher Copyright: © 2023 by the authors.Thyroid diseases affect a considerable portion of the population, with hypothyroidism being one of the most commonly reported thyroid diseases. Levothyroxine (T4) is clinically used to treat hypothyroidism and suppress thyroid stimulating hormone secretion in other thyroid diseases. In this work, an attempt to improve T4 solubility is made through the synthesis of ionic liquids (ILs) based on this drug. In this context, [Na][T4] was combined with choline [Ch]+ and 1-(2-hydroxyethyl)-3-methylimidazolium [C2OHMiM]+ cations in order to prepare the desired T4-ILs. All compounds were characterized by NMR, ATR-FTIR, elemental analysis, and DSC, aiming to check their chemical structure, purities, and thermal properties. The serum, water, and PBS solubilities of the T4-ILs were compared to [Na][T4], as well as the permeability assays. It is important to note an improved adsorption capacity, in which no significant cytotoxicity was observed against L929 cells. [C2OHMiM][T4] seems to be a good alternative to the commercial levothyroxine sodium salt with promising bioavailability.publishersversionpublishe

A bio-based alginate aerogel as an ionic liquid support for the efficient synthesis of cyclic carbonates from co2 and epoxides

Funding Information: This work was supported by Ministerio de Ciencia y Universidades (project RTI2018-097456-B-I00) and Funda??o para a Ci?ncia e Tecnologia FCT/MCTES (project PTDC/EQU-EPQ/31926/2017), UIDB/50006/2020 of the Associate Laboratory for Green Chemistry?LAQV and UIDB/00100/2020 of Centro de Qu?mica Estrutural. This work was also supported by a Short Term Scientific Mission of the CMST COST Action CM1206. A.B. Paninho is thankful to FCT for the doctoral fellowship PD/BD/52497/2014 and pos-doctoral fellowship PTDC/EQU-EPQ/31926/2017. The authors also thanks to the project ?SunStorage-Harvesting and storage of solar energy?, with reference POCI-01-0145-FEDER-016387, funded by European Regional Development Fund (ERDF), through COMPETE 2020-Operational Program. The NMR spectrometers at FCT NOVA are part of Rede Nacional de RMN (PTNMR), supported by FCT/MCTES through ROTEIRO/0031/2013? PINFRA/22161/2016 and co-financed by FEDER through COMPETE 2020, POCI, and PORL and FCT/MCTES through PIDDAC.In this work, the ionic liquid [Aliquat][Cl] was supported into alginate and silica aerogel matrices and applied as a catalyst in the cycloaddition reaction between CO2 and a bio-based epoxide (limonene oxide). The efficiency of the alginate aerogel system is much higher than that of the silica one. The method of wet impregnation was used for the impregnation of the aerogel with [Aliquat][Cl] and a zinc complex. The procedure originated a well-defined thin solvent film on the surface of support materials. Final materials were characterised by Fourier Transform Infrared Spectroscopy, N2 Adsorption–Desorption Analysis, X-ray diffraction, atomic absorption and Field Emission Scanning Microscopy. Several catalytic tests were performed in a high-pressure apparatus at 353.2 K and 4 MPa of CO2.publishersversionpublishe

High pressure phase behavior of the binary system (ethyl lactate + carbon dioxide)

In this work the phase behavior of the binary system (ethyl lactate + CO2) was studied in the pressure range 0.4–17 MPa and at temperatures of 313.2, 333.2, 353.2, 373.2 and 393.2 K. Experiments were performed using the static synthetic method in a high pressure variable–volume view cell. Equilibrium data were correlated with the Peng–Robinson equation of state combined with the Mathias–Klotz–Prausnitz mixing rule. Additionally, density-based correlations, namely Chrastil's and Fornari's equations were used in order to correlate solubilities in both liquid and vapor phases

(Ethyl lactate)-gel high pressure CO2 extraction for the processing of mesoporous gelatine particles

(Ethyl lactate)-gel high pressure CO2 extraction was successfully used as final step for mesoporous gelatine particles preparation. Gelatine spherical microparticles were produced by the water in oil (W/O) emulsion method and further cross-linked with vanillin, to increase its biodegradation resistance. A multi-step solvent exchange of water by ethyl lactate was performed and the gel particles were dried using a semi-continuous high pressure CO2 extraction process. Ethyl lactate was used in this work as an alternative solvent due to high affinity to CO2 and its benign and green nature. The effect of different parameters, such as solvent exchange temperature and the CO2 extraction operating conditions were investigated. The (CO2 + ethyl lactate) binary mixture composition at the beginning of supercritical extraction process has proven to be an important parameter, considerably influencing textural properties of final dried microspheres. Surface areas of 10 to 300 cm2 g−1 and pore diameters from 10 to 17 nm were obtained as the quantity of CO2 in the mixture decreased. (Ethyl lactate)-gel high pressure CO2 drying revealed to be a feasible alternative, enabling a “supercritical-control” approach of gelatine microspheres textural properties

Application of Covalent Organic Frameworks (COFs) as Dyes and Additives for Dye-Sensitized Solar Cells (DSSCs)

Five Covalent Organic Frameworks (COFs) were synthesized and applied to Dye-Sensitized Solar Cells (DSSCs) as dyes and additives. These porous nanomaterials are based on cheap, abundant commercially available ionic dyes (thionin acetate RIO-43, Bismarck brown Y RIO-55 and pararosaniline hydrochloride RIO-70), and antibiotics (dapsone RIO-60) are used as building blocks. The reticular innovative organic framework RIO-60 is the most promising dye for DSSCs. It possesses a short-circuit current density (Jsc) of 1.00 mA/cm2, an open-circuit voltage (Voc) of 329 mV, a fill factor (FF) of 0.59, and a cell efficiency (η) of 0.19%. These values are higher than those previously reported for COFs in similar devices. This first approach using the RIO family provides a good perspective on its application in DSSCs as a dye or photoanode dye enhancer, helping to increase the cell’s lifespan

Styrene carbonate synthesis from CO2 using tetrabutylammonium bromide as a non-supported heterogeneous catalyst phase

The production of cyclic styrene carbonate from CO2 cycloaddition to styrene oxide, using tetrabutylammonium bromide (TBABr) as catalyst, was investigated. Two different reaction systems, a CO2-rich and an epoxide-rich were studied. Reactions were performed in a visual high pressure cell, at different temperatures (313.2, 333.2, and 353.2 K) and pressures (0.5-18 MPa). High pressure phase behaviour manipulation of the reaction system was explored to shift catalysis from homogeneous to heterogeneous, by changing operation conditions. Styrene carbonate formation was monitored quantitatively by using 1H-NMR spectroscopy

Solubility and phase behaviour of binary systems containing salts based on transitional metals

Tri(1-ethyl-3-methylimidazolium) gadolinium hexachloride ([emim]3[GdCl6]), tri(1-butyl-3-methylimidazolium) hexagadolinium chloride ([bmim]3[GdCl6]), di(tetramethylammonium) manganese tetrachloride ([TMA]2[MnCl4]) and cholinium tetrachloroferrate ([Chol][FeCl4]) were synthetized and their solubility in water, ethanol, 1-propanol and 1-butanol were determined as a funcion of temperature. Activity coefficients were calculated and their comparison with ideal solutions were discussed. The experimental data were correlated successfully by means of the semi-empirical Grant equation. In addition, melting point depression effect of high pressure carbon dioxide was studied

Biocompatible choline based ionic salts:solubility in short-chain alcohols

In this work we report data on solubility of choline chloride and choline acetate in shortchain linear alcohols (ethanol, 1-propanol and 1-butanol) at various temperatures. Furthermore, we synthetized two choline derivatives: hydrogen choline chloride glutarate ([CholGlut][Cl]) and hydrogen choline chloride succinate ([CholSucc][Cl]). Their characterization and solubility in short-chain alcohols as a function of temperature are also included. Activity coefficients were calculated and their comparisons with ideal solutions were discussed. The experimental data were correlated successfully by means of the semi-empirical Grant equation