Scale of synthesis	0.02 µmol	0.05 µmol	0.20 µmol	1.0 µmol	10 µmol
Length restriction	N/A	12-140	6-140	6-140	6-140
Minimum yield 20 nucleotides	N/A	2-5 OD	5-15 OD	15-40 OD	150-200

 

Reverse-phase HPLC operates on the same principle as the RPC. The basis of the separation is the difference in hydrophobicity between full-length product (which contains a 5'-DMT) and truncated sequences (without DMT groups). The hydrophobic DMT group is removed after the purification.The capacity and resolving properties of HPLC columns are more powerful than obtained by RPC. The typical yield is a product of 90-97% purity.  

Fig. 3 Crude oligo in purification process. The large peak is collected. This peak contains only full-length product. The residual, containing truncated failure sequences, is wasted.