EFFECTS ON ANALYTE PEAK PERFORMANCE BY SEPARATED SYSTEM PEAKS IN ION-PAIR ADSORPTION CHROMATOGRAPHY

Organic ionic components added to the eluent in ion-pair chromatography often have retention volumes similar to the analytes. The performance of analyte peaks may be influenced by the system peaks derived from such mobile phase components. Earlier work has mainly dealt with situations in which the retention times of analyte and system peaks are close. However, distortions of analyte peaks (peak deformation and peak compression) can be caused by large system peaks even when the two different kinds of peaks are separated. In this work, systematic investigations of this situation were performed. It was found that the analyte peaks were more easily deformed by counter-ion system peaks than by co-ion system peaks. In addition, guidelines are given for the design of general ion-pair chromatographic systems which do not suffer from peak distortion effects.