Reversed-phase liquid chromatography using monoalkylammonium compounds in the mobile phase: Effects of monoalkylammonium chain length on the efficiency, selectivity and separation of xanthine and uric acid derivatives

A systematic analysis of the influence of several chromatographic parameters on the adsorption of monoalkylammonium modifiers on a chemically bonded phase in reversed-phase high performance liquid chromatography is presented. The most important variables are the alkyl chain length, the concentration of the monoalkylammonium modifiers and the acetonitrile content in the mobile phase. The results can be applied to the separation and structure determination of xanthine and uric acid derivatives and to the study of retention mechanisms.