Abolghasem Jouyban
1,2, Fleming Martínez
3*1 Pharmaceutical Analysis Research Center and Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran.
2 Kimia Idea Pardaz Azarbayjan (KIPA) Science Based Company, Tabriz University of Medical Sciences, Tabriz, Iran.
3 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.
Abstract
Background: Recently Haq et
al. reported the equilibrium solubility in {2-propanol (1) + water (2)}
mixtures at several temperatures with some numerical correlation analysis.
Nevertheless, no attempt was made to evaluate the preferential solvation of
this compound by the solvents.
Methods: Preferential solvation of ferulic acid in the
saturated mixtures at 298.15 K was analyzed based on the inverse Kirkwood-Buff
integrals as described in the literature.
Results: Ferulic acid is preferentially solvated by water in
water-rich mixtures (0.00 < x1
< 0.19) but preferentially solvated by 2-propanol in mixtures with
composition 0.19 < x1
< 1.00.
Conclusion: These results could be interpreted as a consequence
of hydrophobic hydration around the non-polar groups of the solute in the
former case (0.00 < x1
< 0.19). Moreover, in the last case (0.19 < x1 < 1.00), the observed trend could be a consequence
of the acid behavior of ferulic acid in front to 2-propanol molecules because
this cosolvent is more basic than water as described by the respective
solvatochromic parameters.