Chiral separation of catechin by capillary electrophoresis using mono-, di-, tri-succinyl-beta-cyclodextrin as chiral selectors.

The chiral separation of (+/-)-catechin was investigated by capillary electrophoresis using characterized succinyl-beta-cyclodextrins (Suc-beta-CDs) with one to three degree of substitution values. The effects of nature and concentration of Suc-beta-CDs and running buffer pH on the migration time and resolution of (+/-)-catechin are discussed. All three kinds of Suc-beta-CDs show a clear baseline separation of (+/-)-catechin in capillary electrophoresis. Mono-Suc-beta-CD effectively separated (+/-)-catechin, and additional substituted CDs (di- and tri-Suc-beta-CD) were capable of chiral separation at a broad pH range. The optimum running conditions were found to be 100 mM borate buffer (pH 9.8) containing 5 mM mono-Suc-beta-CD with no methanol organic modifier.