Determination of ascorbic acid in vegetables by capillary zone electrophoresis

Capillary zone electrophoresis (CZE) was used for the determination of ascorbic acid (AsA) in vegetables. AsA was extracted from vegetables by homogenizing with 2% thiourea-10 mM hydrochloric acid and determined directly by CZE with a borate buffer. The limit of detection (LOD) for AsA was 0.35 mg/l (S/N=3). Relative standard deviations of peak area and migration time for AsA in vegetables were 8.7 and 0.3%, respectively. Recovery of AsA was 97-112%. AsA concentrations in various vegetables were determined by the method. The method was also used for the determination of AsA in vegetables that had been cultivated by using fermented blue mussels, to examine their usefulness as a fertilizer for vegetables.