Evaluation of hydrophilic interaction liquid chromatography stationary phases for analysis of opium alkaloids.

•The separation and purification of five natural opioids were tested on five different HILIC stationary phases.•The mechanism of separation on different HILIC media based on water layer on HILIC stationary phases and are discussed.•The diol stationary phase was found to be more is suitable for analytical chromatography.•Bare silica and zwitterionic stationary phases are appropriate for preparative purposes.