Determination of ascorbic acid based on the combination of capillary electrophoresis and chemiluminescence
YANG Weiping1， ZHENG Xingwang2
(1 School of Ethnic Education， Shaanxi Normal University, Xi′an 710062, Shaanxi, China; 2 School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi′an 710119, Shaanxi, China)
Abstract:
A sensitive method for the determination of ascorbic acid based on the combination of electrophoresis separation and chemiluminescence was developed.The method was based on the reduction of Cr(Ⅵ) to Cr(Ⅲ) with ascorbic acid occurring inside the capillary and the light emission produced by luminol oxidation by hydrogen peroxide in basic aqueous solution catalyzed by Cr(Ⅲ).Running buffer was composed of 0.02 mol/L HAc-NaAc (pH 4.7) with 1×10-3mol/L EDTA,and parameters affecting CE-CL separation and detection were optimized.The limit of detection for ascorbic acid (3σ) was 6×10-11 mol/L.This method offered potential advantages of simplicity, sensitivity, selectivity and applicability to the determination of ascorbic acid in blood samples.
KeyWords:
capillary electrophoresis； chemiluminescence； ascorbic acid； in-capillary reaction
