Charged For Action: The Hidden Secrets Of AEX Oligonucleotide Analysis

Precision in oligonucleotide analysis relies heavily on understanding the molecule’s inherent physical properties. In this second chapter of our nine-part series, we explore how Anion Exchange Chromatography (AEX) leverages the negatively charged phosphate backbone for high-resolution separation. Because an oligonucleotide’s charge scales directly with its length, AEX becomes the ideal method for distinguishing full-length products from truncated n-1 or n-2 impurities.

The process hinges on a delicate balance between the charged stationary phase and salt gradients in the mobile phase. By fine-tuning these ionic interactions during the elution step, laboratories can achieve the linearity and predictability required to validate complex therapeutics. Access the full analysis to review the five-step AEX procedure and learn how to better control elution strength for sharper peaks and dependable results.