Improved measurement of iodine in food samples using inductively coupled plasma isotope dilution mass spectrometry

• Published in: Analyst (London) Vol. 125; no. 11; pp. 1977 - 1982
• Main Authors: HALDIMANN, Max, EASTGATE, Alan, ZIMMERLI, Bernhard
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 01.01.2000
• Subjects: Analytical chemistry; Biological and medical sciences; Chemistry; Exact sciences and technology; Food Analysis - methods; Food industries; Fundamental and applied biological sciences. Psychology; General aspects; Iodine - analysis; Mass Spectrometry - methods; Methods of analysis, processing and quality control, regulation, standards; Spectrometric and optical methods; Chemical analysis; Coupled method; Isotope dilution; Foodstuff; Inductive coupling plasma spectrometry; Certified reference material; Sample preparation; Mineralization; Food industry; Quality control; Acid digestion; Mass spectrometry; Quantitative analysis; Iodine
• ISSN: 0003-2654; 1364-5528
• DOI: 10.1039/b005879n

A new ICP-MS method for the determination of iodine in food samples is presented. The method makes use of a new miniature cyclonic spray chamber and a concentric glass nebulizer that is designed for low sample uptakes and is operated in a self-aspirating mode. As a consequence the wash-out was accelerated over conventional systems. This configuration allows the direct determination of iodine in mineralized solutions following digestion with nitric acid only. No strong oxidizing reagents such as perchloric acid or lengthy sample preparation were necessary to alter the chemical form of potentially volatile species. The isotope dilution technique using the long-lived isotope 129I was applied to obtain freedom from matrix effects. The present study reports on results for total iodine in selected nutritional and biological reference materials and makes a comparison with instrumental neutron activation analysis.