Figure 1.

RPLC separation of oligoribonucleotides under different solvent conditions. The oligoribonucleotide mixture, Dynamarker small RNA kit containing 5-, 8-, 9-, 10-, 20-, 30-, 40-, 50- and 100-nucleotide oligoribonucleotides, was applied to a capillary Develosil C₃₀ column (2.1 mm × 150 mm) and eluted by a 60-min gradient of different mobile phase solvents. The concentration of organic solvent required to elute each oligonucleotide was plotted against the nucleotide length (UV detection at 260 nm). The mobile phase solvents used were TEA–acetate (pH 7.0) in acetonitrile/water (solid line with open triangles); DMBA–acetate (pH 7.0) in acetonitrile/water (solid line with open circles); HFIP–TEA–acetate (pH 7.0) in methanol/water (dotted line with closed triangles); HFIP–DMBA–acetate (pH 7.0) in methanol/water (dotted line with closed circles); TEA–acetate (pH 7.0) in methanol/water (bold line with open triangles); DMBA–acetate (pH 7.0) in methanol/water (bold line with open circles).