The most commonly requested method for oligonucleotide purification is high performance liquid chromatography (HPLC). Anion exchange (AX) HPLC, which separates on the basis of charge to mass, is best for removing shorter fragments and oxygenated species from phosphorothioate oligonucleotides. Therefore, this is our preferred method for manufacturing large scale phosphorothioate oligonucleotides.
We can also purify by AX-HPLC for RNA oligonucleotides, 15 µmole starting synthesis scale and greater. Although our preferred method for syntheses under 15 µmoles is PAGE, it is more cost effective and efficient to purify RNA oligonucleotides by AX-HPLC. Related Article(s)When is my Oligonucleotide Pure Enough?