Estudo da adsorção de brometo de etídeo em resina XAD-7 Study of ethidium bromide adsorption on XAD-7 resin

Abstract

The adsorption of ethidium bromide on XAD-7 resin was studied. The Freundlich model was the most representative isotherm model to describe the sorption behavior. A solid-liquid equilibrium model was proposed to explain the resin mass influence on the sorption. The equilibrium constant value estimated was 2.31. The results showed an ethidium bromide ion-pair physical adsorption, with adsorption enthalpy equals to -19.33 kJ/mol. A pK2 value equals to 4.69 ± 0.01 was estimated by two distinct methods. The results will be applied to the ethidium bromide preconcentration aiming its decomposition.

Keywords

• ethidium bromide
• XAD-7 resin
• adsorption isotherm