title: Determination of Vitamin C (Ascorbic Acid) Using High Performance Liquid Chromatography Coupled with Electrochemical Detection.
abstract: Vitamin C (ascorbic acid, ascorbate, AA) is a water soluble organic compound that participates in many biological processes. The main aim of this paper was to utilize two electrochemical detectors (amperometric - Coulouchem III and coulometric - CoulArray) coupled with flow injection analysis for the detection of ascorbic acid. Primarily, we optimized the experimental conditions. The optimized conditions were as follows: detector potential 100 mV, temperature 25 °C, mobile phase 0.09% TFA:ACN, 3:97 (v/v) and flow rate 0.13 mL·min-1. The tangents of the calibration curves were 0.3788 for the coulometric method and 0.0136 for the amperometric one. The tangent of the calibration curve measured by the coulometric detector was almost 30 times higher than the tangent measured by the amperometric detector. Consequently, we coupled a CoulArray electrochemical detector with high performance liquid chromatography and estimated the detection limit for AA as 90 nM (450 fmol per 5 μL injection). The method was used for the determination of vitamin C in a pharmaceutical preparations (98 ± 2 mg per tablet), in oranges (Citrus aurantium) (varied from 30 to 56 mg/100 g fresh weight), in apples (Malus sp.) (varied from 11 to 19 mg/100 g fresh weight), and in human blood serum (varied from 38 to 78 μM). The recoveries were also determined.
authors.affiliation: Department of Breeding and Propagation of Horticultural Plants, Faculty of Horticulture, Valticka 337, CZ-691 44 Lednice, Faculty of Agronomy, Zemedelska 1, CZ-613 00 Brno, Mendel University of Agriculture and Forestry, Czech Republic.|Department of Agrochemistry, Soil Science, Microbiology and Plant Nutrition, Faculty of Agronomy, Zemedelska 1, CZ-613 00 Brno, Mendel University of Agriculture and Forestry, Czech Republic.
authors.forename: Zbynek
authors.initials: Z
authors.lastname: Gazdik
authors.affiliation: Department of Chemistry and Biochemistry, Faculty of Agronomy, Zemedelska 1, CZ-613 00 Brno, Mendel University of Agriculture and Forestry, Czech Republic.
authors.forename: Ondrej
authors.initials: O
authors.lastname: Zitka
authors.affiliation: Department of Chemistry and Biochemistry, Faculty of Agronomy, Zemedelska 1, CZ-613 00 Brno, Mendel University of Agriculture and Forestry, Czech Republic.
authors.forename: Jitka
authors.initials: J
authors.lastname: Petrlova
authors.affiliation: Department of Chemistry and Biochemistry, Faculty of Agronomy, Zemedelska 1, CZ-613 00 Brno, Mendel University of Agriculture and Forestry, Czech Republic.|Department of Animal Nutrition and Forage Production, Faculty of Agronomy, Zemedelska 1, CZ- 613 00 Brno, Mendel University of Agriculture and Forestry, Czech Republic.
authors.forename: Vojtech
authors.initials: V
authors.lastname: Adam
authors.affiliation: Department of Chemistry and Biochemistry, Faculty of Agronomy, Zemedelska 1, CZ-613 00 Brno, Mendel University of Agriculture and Forestry, Czech Republic.
authors.forename: Josef
authors.initials: J
authors.lastname: Zehnalek
authors.affiliation: Tomas Bata University, T.G. Masaryka 275, CZ-762 72 Zlin, Czech Republic.
authors.forename: Ales
authors.initials: A
authors.lastname: Horna
authors.affiliation: Department of Breeding and Propagation of Horticultural Plants, Faculty of Horticulture, Valticka 337, CZ-691 44 Lednice, Faculty of Agronomy, Zemedelska 1, CZ-613 00 Brno, Mendel University of Agriculture and Forestry, Czech Republic.
authors.forename: Vojtech
authors.initials: V
authors.lastname: Reznicek
authors.affiliation: Department of Veterinary Ecology and Environmental Protection, Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences, Palackeho 1-3, CZ-612 42 Brno, Czech Republic.
authors.forename: Miroslava
authors.initials: M
authors.lastname: Beklova
authors.affiliation: Department of Breeding and Propagation of Horticultural Plants, Faculty of Horticulture, Valticka 337, CZ-691 44 Lednice, Faculty of Agronomy, Zemedelska 1, CZ-613 00 Brno, Mendel University of Agriculture and Forestry, Czech Republic. kizek@sci.muni.cz.
authors.forename: Rene
authors.initials: R
authors.lastname: Kizek
keywords: Ascorbic Acid; Electrochemical Detection; Flow Injection Analysis; Fruits; High Performance Liquid Chromatography; Human Blood Serum; Pharmaceutical Preparation