Flow-injection determination of iodide ion in nuclear emergency tablets, using boron-doped diamond thin film electrode

• Main Authors: Chailapakul O., Amatatongchai M., Wilairat P., Grudpan K., Nacapricha D.
• Format: Conference or Workshop Item
• Language: English
• Published: 2014
• Online Access: http://www.scopus.com/inward/record.url?eid=2-s2.0-7044229330&partnerID=40&md5=0acb42f38da2d9470a356b709d71daa5; http://cmuir.cmu.ac.th/handle/6653943832/6233
• Institution: Chiang Mai University

The electrochemical determination of iodide was studied at boron-doped diamond thin film electrodes (BDD) using cyclic voltammetry (CV) and flow-injection (FI) analysis, with amperometric detection. Cyclic voltammetry of iodide was conducted in a phosphate buffer pH 5. Experiments were performed using glassy carbon (GC) electrode as a comparison. Well-defined oxidation waves of the quasi-reversible cyclic voltammograms were observed at both electrodes. Voltammetric signal-to-background ratios (S/B) were comparable. However, the GC electrode gives much greater in the background current as usual. The potential sweep rate dependence exhibited that the peak current of iodide oxidation at 1 mM varied linearly (r2 = 0.998) with the square root of the scan rate, from 0.01 to 0.30 V s-1. This result indicates that the reaction is a diffusion-controlled process with negligible adsorption on BDD surface, at this iodide concentration. Results of the flow-injection analysis show a highly reproducible amperometric response. The linear working range was observed up to 200 μM (r2 = 0.999). The detection limit, as low as 0.01 μM (3σ of blank), was obtained. This method was successfully applied for quantification of iodide contents in nuclear emergency tablets. © 2004 Elsevier B.V. All rights reserved.