Solubility of sulphadiazine in some {Carbitol® (1) + water (2)} mixtures: determination, correlation, and preferential solvation

ABSTRACT

The mole fraction solubility of sulphadiazine (SD) in {Carbitol® (1) + water (2)} binary solvent mixtures at different temperatures from (278.15 to 313.15) K was determined. Solubility values were correlated with the combined nearly ideal binary solvent/Redlich-Kister, modified Wilson and Jouyban-Acree models. Preferential solvation parameters of SD by Carbitol® (δx_1,3) were derived from their thermodynamic solution properties using the inverse Kirkwood-Buff integrals method. δx_1,3 values are negative in water-rich mixtures but positive in Carbitol® mole fractions higher than 0.12. In the former case is conjecturable that hydrophobic hydration around non-polar groups of SD plays a relevant role in drug solvation.

KEYWORDS:

• Sulphadiazine
• Carbitol®
• solubility
• Jouyban-Acree model
• preferential solvation

Acknowledgements

We thank the Department of Pharmacy of the National University of Colombia for facilitating the equipment and laboratories used.

Disclosure statement

No potential conflict of interest was reported by the authors.