Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/34791
標題: Flow injection analysis of ascorbic acid in real samples using a highly stable chemically modified screen-printed electrode
作者: Zen, J.M.
曾志明
Tsai, D.M.
Kumar, A.S.
關鍵字: ascorbic acid
sol-gel
Tosflex
screen-printed electrode
amperometric determination
carbon electrodes
reaction rates
期刊/報告no:: Electroanalysis, Volume 15, Issue 14, Page(s) 1171-1176.
摘要: A silica sol-gel glass-coated ferricyanide-doped Tosflex-modified screen-printed electrode (designated as SG/FeCN-Ts/SPE) was used for the mediated oxidation of ascorbic acid in neutral pH. The sol-gel overlayer was found to stabilize the Fe(CN)(6)(3-)-Tosflex system without any foul-off and deterioration behavior through chemical interaction between the hydrophilic sites of Tosflex and oxy- and/or -hydroxy surface functional groups of silicate. The electrochemical mediation of ascorbic acid was found to follow the Michaelis-Menten kinetic pathway. The SG/FeCN-Ts/SPE was very stable for repetitive measurements by flow injection analysis at 0.3 V (vs. Ag/AgCl). A linear calibration plot was obtained for ascorbic acid determination up to 300 muM with sensitivity and detection limit (S/N = 3) of 2.85 nA/muM and 46 nM, respectively. The system also showed tolerable interference to uric acid, urea and carbohydrates and was used for the determination of ascorbic acid in human urine, clinical tablet and apple juice.
URI: http://hdl.handle.net/11455/34791
ISSN: 1040-0397
Appears in Collections:化學系所

文件中的檔案:

取得全文請前往華藝線上圖書館



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.