Purification of a HEX BHQ oligonucleotide probe on an ARION® Plus C18, 5.0 µm column (100 mm × 4.6 mm, ARI-5720-LI46). Gradient elution with (A) 50 mM TEAA and (B) MeOH : acetonitrile (1 : 1 v/v), injection 50 µl, ambient temperature, DAD and FLD detection at 534 nm (Ex) / 556 nm (Em); the flow rate is proprietary. The ARION® column delivers a sharp, symmetrical product peak, while the competitor BDS and BDS-clone columns give broad, partly unresolved peaks under the same conditions.