Selectivity limits of and opportunities for ion pair chromatographic separation of oligonucleotides

Here it was investigated how oligonucleotide retention and selectivity factors are affected by electrostatic non-electrostatic interactions in ion pair chromatography. A framework derived describing depends on the potential generated ion-pair reagent concentration, co-solvent volume fraction, charge difference between analytes, temperature. Isocratic experiments verified that, separation problems concerning oligonucleotides of different charges, increases with increasing surface analyte decreasing fraction For analytes same charge, for example, diastereomers phosphorothioated oligonucleotides, can be increased or temperature has only a minor dependency ion-pairing concentration. An important observation is that driven predominantly interaction adsorption reagent. We therefore compared classical gradient elution which over time versus constant but concentration time. Both modes decrease potential. Oligonucleotide found to increase The two were finally applied model antisense problems, shown non-charge–based while maintaining charge-difference–based selectivity.