Sensitive flow-injection amperometric detection of iodide using Mn3+ and As3+.
A rapid, selective, and sensitive kinetic flow-injection method for iodide content determination with amperometric detection on a platinum electrode was developed. The method is based on the catalytic effect of iodide on the Mn3+ reaction with As3+ in the presence of sulfuric acid. The calibration curve was linear in the concentration range from 5.0 x 10(-7) to 1.0 x 10(-4) mol/L iodide. The limit of detection (LOD) was found to be 5.0 x 10(-9) mol/L iodide. The relative standard deviations (RSD) were 1.68% and 3.03% for 1.0 x 10(-3) mol/L standard and 1.0 x 10(-6) mol/L iodide solution (n = 6), respectively. The method has been successfully applied for determination of iodide in waters, table salts, fodder, organic substances and human blood sera. The results were compared with those obtained by a standard AOAC (Association of Official Analytical Chemists) method, as well as with those obtained by a kinetic spectrophotometric procedure for determination of iodide.
Nikolic
Snezana D
SD
Department of Analytical Chemistry, Faculty of Chemistry, P O. Box 550, 11001 Belgrade, Serbia and Montenegro. snezananm@chem.bg.ac.yu
Mutic
Jelena J
JJ
Lolic
Aleksandar D
AD
Manojlovic
Dragan D
DD
D000821:Animal Feed / Q000032:analysis; D001151:Arsenic / Q000032:analysis* / Q000097:blood; D004563:Electrochemistry; D004566:Electrodes; D006801:Humans; D007202:Indicators and Reagents; D007454:Iodides / Q000032:analysis* / Q000097:blood; D008345:Manganese / Q000032:analysis* / Q000097:blood; D010091:Oximes / Q000032:analysis; D010984:Platinum; D012623:Seawater / Q000032:analysis; D013464:Sulfuric Acids; D014881:Water Supply
D007202:Indicators and Reagents; D007454:Iodides; D010091:Oximes; D013464:Sulfuric Acids; D008345:Manganese; D010984:Platinum; D001151:Arsenic