THERMODYNAMICS OF THE MIXING PROCESS OF SEVERAL SODIUM SULFONAMIDES IN ETHANOL + WATER COSOLVENT MIXTURES

Sodium sulfonamides have been extensively used for the treatment of certain infections caused by several types of microorganisms. Although sulfonamides are still widely used in therapeutics, the physicochemical information about their aqueous solutions has not been completed. In this context, the th...

Description complète

Enregistré dans:
Détails bibliographiques
Auteurs principaux: Daniel R. DELGADO, Edgar F. VARGAS, Fleming MARTÍNEZ
Format: article
Langue:EN
Publié: Universidad de Antioquia 2011
Sujets:
Accès en ligne:https://doaj.org/article/f4b32150a0e34b73a2a6210e7b0a0843
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
Description
Résumé:Sodium sulfonamides have been extensively used for the treatment of certain infections caused by several types of microorganisms. Although sulfonamides are still widely used in therapeutics, the physicochemical information about their aqueous solutions has not been completed. In this context, the thermodynamic functions of mixing three structurally related sodium sulfonamides were evaluated: Gibbs energy, enthalpy, and entropy. The quantities of mixing were calculated based on the fusion calorimetric values obtained from differential scanning calorimetry measurements and equilibrium solubility values reported in the literature for all the drugs with ethanol + water mixtures. By means of an enthalpy-entropy compensation analysis, non-linear ΔH0mix vs. ΔG0mix plots with negative slopes from neat ethanol to a 0.60 ethanol mass fraction, and positive slopes from the latter composition to neat water were obtained. From these results, it was concluded that the dissolution process of these drugs in ethanol-rich mixtures was entropy-driven; whereas, in water-rich mixtures the process was enthalpy-driven. Nevertheless, the molecular and ionic events involved in the dissolution of these drugs in this cosolvent system remain unclear.