abstract
The solubilities of gallic, protocatechuic, gentisic or alpha-resorcylic acids were measured in nine pure solvents (water, methanol, ethanol, 1-propanol, 2-propanol, 2-butanone, ethyl acetate, acetonitrile and dimethylformamide) at 298.15 K and 313.15 K, using the analytical isothermal shake-flask method. Additionally, solid phase studies of the selected phenolic acids were carried out using differential scanning calorimetry (DSC) and X-ray diffraction (XRD), giving access to important data on melting properties as well as on the structure of the solid phase before and after the dissolution. The NRTL-SAC model coupled to the reference solvent approach (RSA) were applied to correlate the solubility data in a set of seven solvents and, after used to predict the solubility in 1-propanol and dimethylformamide. Average relative deviations (ARD) between 28 and 40% for the correlation and between 16 and 59% for the predictions were obtained. These values are within the order of magnitude usually found for such type of semipredictive models, using a limited set of data. (C) 2018 Elsevier B.V. All rights reserved.
keywords
ACTIVITY-COEFFICIENT MODEL; DRUG MOLECULE SOLUBILITY; MEDIUM-SIZED CHEMICALS; GALLIC ACID; PLUS WATER; PROTOCATECHUIC ACID; AQUEOUS SOLUBILITY; SYSTEM SELECTION; SALICYLIC-ACID; VANILLIC ACID
subject category
Chemistry; Physics
authors
Vilas-Boas, SM; Brandao, P; Martins, MAR; Silva, LP; Schreiner, TB; Fernandes, L; Ferreira, O; Pinho, SP
our authors
Liliana Patrocínio da Silva
Collaborator
Paula Cristina Ferreira da Silva Brandão
Assistant ResearcherProjects
acknowledgements
This work is supported by: Project "AlProcMat@N2020 - Advanced Industrial Processes and Materials for a Sustainable Northern Region of Portugal 2020", supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (ERDF); Project POCI-01-0145-FEDER-006984 - Associate Laboratory LSRE-LCM funded by ERDF through COMPETE2020 - Programa Operacional Competitividade e Internacionalizacao (POCI); Project POCI-01-0145-FEDER-030463 financed by COMPETE and Portugal2020 and national funds through FCT - Fundacao para a Ciencia e a Tecnologia. We also acknowledge the support of CICECO - Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (Ref. FCT UID/CTM/50011/2013).