Determination of 10 phenolic compounds in extract from Bidens bipinnata by HPCE / 中草药

ABSTRACT

Objective: To develop a novel method using high-performance capillary electrophoresis coupled with DAD (HPCE-DAD) for the simultaneous determination of 10 phenolic compounds (luteolin-7-O-glucoside, rutin, quercetin-3-glucoside, quercetin-3- rhamnoside, salicylic acid, luteolin, kaemferol, quercetin, gallic acid, and protocatechuic acid) in Bidens bipinnata. The extraction efficiency of above mentioned compounds was compared using six different ethanol/water solutions. Methods: The effects of pH value and concentration of buffer, applied voltage, and temperature on the separation were researched. The 10 compounds were baseline separated within 16 min in a 60 cm length capillary at a separation voltage of 25 kV with a running buffer consisting of 25 mmol/L borate (pH 9.5) at wavelength of 214 nm. Results: Excellent linearities of luteolin-7-O-glucoside, rutin, quercetin-3-glucoside, quercetin-3-rhamnoside, salicylic acid, luteolin, kaemferol, quercetin, gallic acid, and protocatechuic acid were observed at 5.0-120, 5.0-120, 5.0-120, 5.0-120, 1.0-120, 2.5-120, 5.0-120, 2.5-120, 2.5-120, and 2.5-120 mg/L, respectively. The detection limits were at 2.5, 2.5, 2.5, 2.5, 0.5, 1.0, 2.5, 1.0, 1.0, and 1.0 mg/L, respectively. The relative standard deviations (RSD) of precision were below 5.17% (n = 6). The mean recoveries for 10 phenolic compounds in B. bipinnata ranged from 94.4% to 105.8%, with RSD values of 0.32%-4.33%. Conclusion: The contents of luteolin-7-O-glucoside, rutin, quercetin-3- glucoside, quercetin-3-rhamnoside, salicylic acid, luteolin, kaemferol, quercetin, gallic acid, and protocatechuic acid in B. bipinnata are 95.04-105.84, 78.03-110.45, 96.45-177.96, 178.78-300.00, 62.06-66.54, 71.08-72.85, 77.39-95.30, 68.27-77.43, 68.47- 88.47, and 107.24-142.43 μg/g, respectively.