Determination pk a Values of Six Phenolic Acids by Pressure-Assisted Capillary Electrophoresis and Simultaneous Determination of These Six Phenolic Acids in Euphorbiae Lathyris L. By Capillary Zone Electrophoresis with Heptapkis (2,6-di-o-Methyl)-β-Cyclodextrin as Modifier
24 Pages Posted: 14 Jan 2022
Abstract
The purpose of this study was to determine the pΚa values of six phenolic acids (Chlorogenic acid, Ferulic acid, p-Coumaric acid, Vanillic acid, Caffeic acid and Gallic acid) by pressure-assisted capillary electrophoresis and develop a capillary zone electrophoresis method (CZE) for simultaneous separation and determination of these six phenolic acids in Euphorbiae Lathyris L. The measured pΚa values for the six phenolic acids were Chlorogenic acid (3.96), Ferulic acid (4.57), p-Coumaric acid (4.65), Vanillic acid (4.56), Caffeic acid (4.63) and Gallic acid (4.40), respectively. These six analytes were baseline separated within 15 minutes with a running buffer consisting of 35 mM sodium tetraborate and 3.0 mM Heptapkis (2,6-di-o-Methyl)-β-cyclodextrin (DM-β-CD) in water-methanol (95:5, v/v) (pH=9.18). The applied voltage, capillary temperature and detection wavelength were 12.5 kV, 25°C and 260 nm, respectively. Under the optimum conditions, good linearities were achieved with correlation coefficients from 0.9925 to 0.9990. The detection limits and the quantitation limits ranged from 0.08 to 0.65 μg/mL and from 0.30 to 1.95 μg/mL, respectively. Excellent accuracy and precision were obtained. Recoveries of the analytes varied from 98.2% to 104.9%. This established method was novel, simple, rapid, and it was successfully used in the analysis of these phenolic acids in Euphorbiae Lathyris L. with relatively simple extraction procedures, the assay results were satisfactory.
Keywords: Euphorbiae Lathyris L., acid-base dissociation constants, pressure-assisted capillary electrophoresis, Heptapkis (2, 6-di-o-Methyl)-β-cyclodextrin
Suggested Citation: Suggested Citation