The unique combination of hydrophobic and hydrophilic functions in the Acclaim Mixed-Mode HILIC-1 column enable it to perform in both reversed-phase and normal-phase modes, simply by changing the organic/aqueous ratio in the mobile phase. Here, chromatography of a nonionic detergent is used to demonstrate the transition between modes. Below 75% acetonitrile, the column is in reversed-phase mode and retention increases with decreasing organic modifier. Above 90%, the column separates in normal-phase mode and retention increases with increasing acetonitrile content.