Effect of the pH and the ionic strength on overloaded band profiles of weak bases onto neutral and charged surface hybrid stationary phases in reversed-phase liquid chromatography

► The adsorption behavior of weak bases on BEH-C18 is heterogeneous at all pH. ► The EML model accounts poorly for changes in this behavior at increasing ionic strength. ► The adsorption behavior of weak bases on CSH-C18 is heterogeneous at pH > 5. ► This behavior is practically homogeneous at pH < 3.