Influence of the Structure of the Amine Modifiers on the Mechanism of the Separation of Basic Compounds by Reversed-Phase High-Performance Liquid Chromatography

Abstract

Peak shapes and chromatographic retention for a couple of basic compounds (tabers; nine and methoxy -tabersonine) in reversed-phase high.-performance li -quid chromatography have been studied by the addition of different amine Modifiers to the eluent. A discus -sion on the chromatographic mechanism is presented. It is suggested that the amine modifiers adhere to the hydrocarbon ligands of the bonded phase, thus promoting the mass transfer process of basic solutes between the stationary and liquid phases. A change of the initial hydrophobicity of the octyl ligands occurs, influencing the retention times. The mechanism advanced as being responsible for the unusual variation of elution times was confirmed by the chromatographic behaviour of twelve basic compounds.