An RP monolithic column coated with an amphoteric carboxybetaine type surfactant has been used with a combined triple eluent concentration, pH and flow gradient ion chromatography technique for the simultaneous separation of up to 18 nucleotides, nucleosides and nucleobases. The separation of up to eight precursors on a 1 cm long monolithic microcolumn using the combined gradient approach is also shown. The method was applied to the separation of the above nucleic acid precursors in perchloric acid extracts of yeastolates samples.

Up to ten individual reversed-phase monolithic LC columns were efficiently coupled to equal a total column length of 1 m. The column generated up to 90,000 theoretical plates under optimum conditions with a peak capacity under gradient conditions of 244 peaks h(-1) at a total column backpressure of just 140 bar, directly coupled to ESI-MS.