37 documents found, page 1 of 4
Using Molecular Conformers in COSMO-RS to Predict Drug Solubility in Mixed Solv...
Cordova, Isabella Weber; Teixeira, Gabriel; Ribeiro-Claro, Paulo J.A.; Abranches, Dinis O.; Pinho, Simão; Ferreira, Olga; Coutinho, João A.P.This work explores the impact of solute conformers on the conductor-like screening model for real solvents (COSMO-RS) solubility predictions of vanillin and ethyl vanillin in water, short alcohols, and their mixed solvents. Two major conformers of these solutes and changes with solvent polarity were experimentally established by Raman spectroscopy and further confirmed by density functional theory calculations....
Designing type V deep eutectic solvents with antimalarial pharmaceutical ingred...
Teixeira, Gabriel; Brandão, Paula; Ferreira, Ana I.M.C. Lobo; Abranches, Dinis O.; Santos, L.uís M.N.B.F.; Ferreira, Olga; Coutinho, João A.P.This work studies the formation of deep eutectic solvents formed by one active pharmaceutical ingredient (quinine, pyrimethamine, or 2-phenylimidazopyridine) and a second component potentially acting as an excipient (betaine, choline chloride, tetramethylammonium chloride, thymol, menthol, gallic acid, vanillin, acetovanillone, 4-hydroxybenzaldehyde, syringaldehyde, propyl gallate, propylparaben, or butylated h...
What is better to enhance the solubility of hydrophobic compounds in aqueous so...
Ferreira, Olga; Silva, Liliana P.; Almeida, Heloísa H.S.; Benfica, Jordana; Abranches, Dinis O.; Pinho, Simão; Coutinho, João A.P.The solubilities of benzoic acid, (S)-hesperetin, and L-tryptophan in aqueous solutions of ionic liquids (choline glycolate and choline malonate) and the analogous eutectic solvents (choline chloride:glycolic acid and choline chloride:malonic acid) were studied. It is shown that while ionic liquids (IL) and eutectic solvents (ES) were able to increase the solubility of all compounds studied in aqueous solution,...
Good vibrations: understanding deep eutectic solvents through the lens of vibra...
Araújo, Catarina F.; Abranches, Dinis O.; Coutinho, João A. P.; Vaz, Pedro D.; Ribeiro-Claro, Paulo; Nolasco, Mariela M.This review highlights the variety of ways in which vibrational spectroscopy can be of use in understanding why deep eutectic solvents (DESs) behave the way they do. Throughout six themed sub-sections, selected studies are showcased to illustrate the kind of information that can be garnered using different vibrational spectroscopy techniques, warn against common pitfalls, and advise on best practices. More than...
Tetraalkylammonium Chlorides as Melting Point Depressants of Ionic Liquids
Martins, Mónia A. R.; Abranches, Dinis O.; Silva, Liliana P.; Pinho, Simão; Coutinho, João A.P.With the (re)advent of eutectic mixtures within the field of deep eutectic solvents, special attention has been given to the measurement of solid–liquid equilibrium (SLE) phase diagrams, supported by the relevant information they can provide on the molecular interactions and melting temperature depression of any given system. As such, this work investigates the SLE phase diagrams of mixtures between ionic liqui...
Estimating the melting temperatures of type V deep eutectic solvents
Teixeira, Gabriel; Abranches, Dinis O.; Ferreira, Olga; Coutinho, João A.P.The recently proposed category of type V deep eutectic solvents (DESs), composed only of non-ionic species, has attracted great interest in the literature. However, despite their importance in solvent design, measuring the solid−liquid equilibrium (SLE) diagrams of all possible type V DES precursor combinations is unfeasible. Therefore, a reliable computational tool must be found to estimate SLE phase diagrams ...
Modeling the solubility of monoterpenoids with hybrid and predictive thermodyna...
Vilas-Boas, Sérgio M.; Cordova, Isabella Weber; Abranches, Dinis O.; Coutinho, João A.P.; Ferreira, Olga; Pinho, SimãoThe Abraham and NRTL-SAC semipredictive models were employed to represent the solubility of (-)-borneol, (1R)-(+)-camphor, L-(-)-menthol, and thymol in water and organic solvents, using data measured in this work and collected from the literature. A reduced set of solubility data was used to estimate the model parameters of the solutes, and global average relative deviations (ARDs) of 27% for the Abraham model ...
Liquefying flavonoids with terpenoids through deep eutectic solvent formation
Teixeira, Gabriel; Abranches, Dinis O.; Silva, Liliana P.; Vilas-Boas, Sérgio M.; Pinho, Simão; Ferreira, Ana I.M.C. Lobo; Santos, Luís M.N.B.F.The formation of deep eutectic solvents (DES) is tied to negative deviations to ideality caused by the establishment of stronger interactions in the mixture than in the pure DES precursors. This work tested thymol and menthol as hydrogen bond donors when combined with different flavonoids. Negative deviations from ideality were observed upon mixing thymol with either flavone or flavanone, two parent flavonoids ...
Selection of hydrotropes for enhancing the solubility of artemisinin in aqueous...
Sales, Isabela; Abranches, Dinis O.; Sintra, Tânia E.; Mattedi, Silvana; Freire, Mara G.; Coutinho, João A.P.; Pinho, SimãoArtemisinin is an antimalarial substance very sparingly soluble in water. In the attempt to identify environmental-friendly and non-toxic aqueous-based solvents to extract it from Artemisia annua L., the solubility of artemisinin in aqueous solutions of different hydrotropes was measured at 303.2 K, for hydrotrope concentrations up to 5 M. The ability of the studied hydrotropes for enhancing the artemisinin sol...
Insights into the chloride versus bromide effecton the formation of urea quater...
Martins, Mónia A.R.; Abranches, Dinis O.; Silva, Liliana P.; Pinho, Simão; Coutinho, João A.P.The intermolecular interactions of urea and quaternary ammonium salts relevant to their thermodynamic nonideality were here investigated by measuring the solid-liquid equilibria of their binary mixtures. The experimental data revealed that the anion transfer between the quaternary ammonium salt and urea increases with increasing alkyl chain lengths, leading to negative deviations from ideality in the urea-rich ...