HILIC is a particularly useful separation mode for polar organic compounds. These compounds cannot be retained without HILIC HPLC columns. Retention of these polar compounds using the reversed phase methods is often difficult because of co-elutions with the solvent front or elutions within the chromatographic region where ion suppression is the greatest.
HILIC HPLC/UHPLC columns draw and retain a water-enriched layer onto the surface of the silica, which facilitates the interaction of polar compounds with the stationary phase for increased retention.