Resolution of 1-Benzyl-4-[(5, 6-dimethoxy-1-indanon)-2-yl] Methylpiperidine Hydrochloride Enantiomers in Plasma by High-Performance Liquid Chromatography with Direct Injection Into Avidin-Conjugated Column

A high-performance liquid chromatographic method for the chiral separation of 1-benzyl-4 -[((5, 6-dimethoxy-1-indanon)-2-y1] methylpiperidine hydrochloride (E2020) and its plausible metabolites in plasma has been developed using an avidin column. The hydrophobicity (alkyl chain length) of a spacer, combining avidin to the silica support, affected significantly the retention and separation of E2020 enantiomers. A new column-switching technique using avidin columns for pretreatment and chiral separation enabled the direct injection analysis of plasma samples and the enrichment of E2020, which gave high-sensitivity. This occurs because plasma proteins are excluded from the avidin column, while E2020 enantiomers are retained on the column. This column-switching technique and Liquid chromatography-mass spectrometry were used to separate E2020 enantiomers from its plausible metabolites in plasma. This system enables to determine the level of E2020 enantiomers in plasma with high-selectivity and high-sensitivity without any pretreatments.