Screening and analysis of permeable compounds in Radix Angelica Sinensis with immobilized liposome chromatography

Immobilized liposome chromatography (ILC) was used to screen and analyze permeable compounds in traditional Chinese medicines (TCMs), testing extracts from Radix Angelica Sinensis. More than 10 peaks were resolved based on their interactions with the ILC stationary phase, a system which mimics biomembranes; this means that more than 10 components in Radix Angelica Sinensis extract have significant retention on an ILC column. Two of them, ligustilide and ferulic acid, were identified from their MS spectrum and with standard samples. A possible molecular structure of another component retained on ILC was also preliminarily identified as 3-butylidene-4,5-dihydro-2(1,3H)-1-isobenzofuranoI according to its MS spectrum, hydrophobicity and H-1 NMR spectrum. Of all detected components, ligustilide had the best penetration ability through the biomembrane. The effects of pH, column temperature, and ionic strength on the chromatography of methanolic extracts of Radix Angelica Sinensis were also investigated. It was found that the separation selectivity on ILC is strongly affected by the eluent pH, but only slightly by the column temperature and ionic strength. (C) 2002 Elsevier Science B.V. All rights reserved.