ABSTRACT
The separation and characterization of oligonucleotides and their synthesis side-and by-products pose several challenges for analytical method development. Traditionally, such separations have been done using reversed phase high-performance liquid chromatography (RP-HPLC) owing to the versatility of that analytical technique. Because oligonucleotides are typically highly charged anions in solution, ion-pairing reagents can be added to the RP-HPLC mobile phase to improve resolution. Alternatively, separations based on ion-exchange mechanisms, such as anion-exchange chromatography (AEX-HPLC), have also been popular and useful approaches for the separation of oligonucleotides. Both RP-HPLC and AEX-HPLC are the subject of other chapters in this handbook, and the interested reader is referred there for additional details.
