Aim To investigate the interaction between drugs and ordered phospholipid membrane using immobilized artificial membrane
chromatography (IAMC). Methods IAMC was used to determine the interaction drugs with
phospholipid membrane, expressed as membrane affinity (lg k IAM ). An n octanol/buffer system was also employed as the reference hydrophobicity (lg D O/W,7 4 ). Results Within the range of used acetonitrile percentages (φ) 0～30% in mobile phase, retention index (lg k ′ IAM ) showed excellent correlation with φ. Intercepts of fitted straight lines between lg k ′ IAM and φ were comparable but slopes were much different for the three organic modifiers (acetonitrile, ethanol and methanol). Effects by adding CH 2 substituent on lipophilicity difference (Δlg k IAM and Δlg D O/W,7 4 ) were similar for p hydroxyl benzoic methyl ester to butyl ester, whereas different for p hydroxylbenzoic acid to methyl ester. Conclusion IAMC system is a convenient, efficient and rapid tool for determining membrane interaction.