A B S T R A C T : The interaction of montmorillonite with sotalol hydrochloride (4-(1-hydroxy-Nisopropylaminoethyl) methane sulfanilide) was studied by means of adsorption isotherms, XRD and IR spectroscopy. The amount of sotalol adsorbed depended on pH, the maximum amount adsorbed (0.56 mEq g-l) being considerably less than the exchange capacity of the mineral (0.80 mEq g-l). XRD and IR data revealed that the sotalol is adsorbed into the interlayer space, forming a monolayer complex with a do01 spacing of 17.7 A, and that the mechanisms involved are cation exchange and ion-dipole interactions. Experiments on the in vitro desorption of the drug from the sotalol-montmorillonite complex indicated that desorption is affected by pH, by the salt concentration of the electrolyte, and by the elimination rate of the desorbed organic cations.

Sotalol hydrochloride adsorbed on montmorillonite forms a monolayer complex, with desorption influenced by pH, electrolyte salt concentration, and organic cation elimination rate.

Adsorption-Desorption of Sotalol Hydrochloride by Na-Montmorillonite

Key Takeaway: Sotalol hydrochloride adsorbed on montmorillonite forms a monolayer complex, with desorption influenced by pH, electrolyte salt concentration, and organic cation elimination rate.