Analysis of flavonoids by capillary zone electrophoresis with electrokinetic supercharging

摘要: On-line concentration via Electrokinetic Supercharging (EKS) was used to enhance the sensitivity of capillary electrophoretic separation four flavonoids naringenin, hesperetin, naringin and hesperidin. Separation conditions, including background electrolyte pH concentration, length choice terminator electrokinetic injection time were optimized. The optimum conditions were: a 30 mM sodium tetraborate (pH 9.5) containing 5% (v/v) methanol, sample (130 s, −10 kV) followed by hydrodynamic injecting 100 2-(cyclohexylamino)ethanesulfonic acid (CHES) (17 0.5 psi) as terminator, with −20 kV. Under these could be separated sample-to-sample 15 min detection limits from 2.0 6.8 ng mL−1. When compared conventional enhanced between 824 1515 times which is 7.6-16 higher than other CE methods for on-line flavonoids. applicability developed method demonstrated in an aqueous extract Clematis hexapetala pall.