Flow electrochemical determination of ascorbic acid in real samples using a glassy carbon electrode modified with a cellulose acetate film bearing 2,6-dichlorophenolindophenol

被引:82
作者
Florou, AB [1 ]
Prodromidis, MI [1 ]
Karayannis, MI [1 ]
Tzouwara-Karayanni, SM [1 ]
机构
[1] Univ Ioannina, Dept Chem, GR-45110 Ioannina, Greece
关键词
electrochemical determination of ascorbic acid; controlled porosity cellulose acetate film; beverages; pharmaceuticals; flow injection analysis; 2,6-dichlorophenolindophenol;
D O I
10.1016/S0003-2670(00)00709-1
中图分类号
O65 [分析化学];
学科分类号
070302 ; 081704 ;
摘要
An ascorbate sensor based on a glassy carbon electrode modified with a cellulose acetate polymeric film bearing 2,6-dichlorophenolindophenol (CA/DCPI-CME) was constructed. The overall reaction obeys a catalytic regeneration mechanism (EC mechanism) and the electrochemical rate constant kf for the electrocatalytic oxidation of ascorbic acid was evaluated. The modified electrodes were mounted in a flow injection (FI) manifold, poised at +100 mV versus Ag/AgCl/3 M KCl at pH 6.5 and utilized for the determination of ascorbic acid in beverages and pharmaceuticals. Good correlation with a reference method was attained. Interferents of various molecular sizes were tested. Calibration graphs were linear over the range 0.02-1 and 0.1-6 mM ascorbic acid for CA/DCPI sensors hydrolyzed in KOH and ZnCl2 solution, respectively. The throughput was 25 samples per hour and the CV was for a 0.4 mM ascorbic acid solution 0.75 (n=14) and 1.2% (n=10) for CA/DCPI sensors hydrolyzed in KOH and ZnCl2 solution, respectively. The recovery was 92-110%. The sensors showed very good repeatability and operational stability. (C) 2000 Elsevier Science B.V. All rights reserved.
引用
收藏
页码:113 / 121
页数:9
相关论文
共 29 条
  • [1] ANDRIEUX CP, 1978, J ELECTROANAL CHEM, V93, P163, DOI 10.1016/S0022-0728(78)80230-7
  • [2] ARMSTRONG JM, 1964, BIOCHIM BIOPHYS ACTA, V86, P194
  • [3] Determination of copper by zeolite molecular sieve modified electrode
    Chen, B
    Goh, NK
    Chia, LS
    [J]. ELECTROCHIMICA ACTA, 1997, 42 (04) : 595 - 604
  • [4] CUNNIFF P, 1998, OFFICIAL METHODS ANA, V2, P16
  • [5] Donf S., 1989, ELECTROANAL, V1, P99
  • [6] Florou AB, 1998, ELECTROANAL, V10, P1261, DOI 10.1002/(SICI)1521-4109(199812)10:18<1261::AID-ELAN1261>3.3.CO
  • [7] 2-D
  • [8] FLOROU AB, IN PRESS ELECTROANAL
  • [9] FOX BA, 1989, FOOD SCI NUTR HLTH, P261
  • [10] HAFNEY MK, 1978, ANAL CHEM, V50, P116