Document Type : Regular Article
Pharmaceutical Analysis Research Center and Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
Grupo de Investigaciones Farmacéutico-Fisicoquímicas, Departamento de Farmacia, Facultad de Ciencias, Universidad Nacional de Colombia-Sede Bogotá, Cra. 30 No. 45-03, Bogotá, D.C., Colombia
Pharmaceutical Analysis Research Center and Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran. Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, 5165665811, Tabriz, Iran
Pharmaceutical Analysis Research Center and Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran. Faculty of Pharmacy, Near East University, PO BOX: 99138 Nicosia, North Cyprus, Mersin 10, Turkey
In the current study, the solubility of nicotinamide in all fractions (with 0.1 intervals) of acetonitrile and ethanol mixtures was gravimetrically determined. The results show that maximum solubility was obtained in ethanol mass fraction of 0.8 (xm=8.52×10-2) at 313.2 K and the minimum solubility in the pure acetonitrile (xm=7.33×10-3) at 293.2 K. In the next step, all data are fitted/back-calculated by several mathematical cosolvency equations. Deviation amount of back-calculated data from experimental values (<5.0%) shows the applicability of the models for the prediction of solubility. Also, density data for saturated systems are determined and fitted to the adopted form of the Jouyban-Acree model which obtained a back-calculated MRD% of 0.7%. Furthermore, the thermodynamic behavior of nicotinamide in investigated mixtures was investigated using the calculation of the Gibbs energy, enthalpy, and entropy at Thm. Further, inverse Kirkwood-Buff integrals calculations demonstrated preferential solvation of nicotinamide by acetonitrile in acetonitrile-rich solutions.