In most cases the average level of accuracy and precision in a HILIC analysis for example is less than typical values obtained by Reversed Phase RP HPLC. Reversed Phase methods are not usually effective for polar compounds. It is believed that the accuracy and precision of a HILIC analysis is strongly influenced by the equilibration time if a gradient method is used.
Aqueous Normal Phase ANP may be more suitable than HILIC in terms of accuracy and precision for your polar compound separations. The reason for this is that in HILIC methods, the slow equilibration of the “water monolayers” that are found in HILIC columns is thought to be primarily responsible for retention and is also sometimes variable from run to run. The equilibration in ANP methods is much faster because columns that can produce ANP methods do not have monolayers of water and do not rely on it for retention or separation.
