Clinical Chemistry Link to Randox Laboratories Web Site
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Clinical Chemistry 49: 186-188, 2003; 10.1373/49.1.186
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Submit an electronic Letter to
the Editor about this paper
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via ISI Web of Science (5)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Gnat, D.
Right arrow Articles by Dunn, J. T.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Gnat, D.
Right arrow Articles by Dunn, J. T.
Related Collections
Right arrow General Clinical Chemistry
Right arrow Pediatric Clinical Chemistry
Right arrow Nutrition
Right arrow Endocrinology and Metabolism
Right arrow Automation and Analytical Techniques
(Clinical Chemistry. 2003;49:186-188.)
© 2003 American Association for Clinical Chemistry, Inc.

Technical Briefs

Fast Colorimetric Method for Measuring Urinary Iodine

Daniella Gnat1, Ann D. Dunn2, Samar Chaker1, Francois Delange1,3, Francoise Vertongen1 and John T. Dunn2,3a

1 Centre Hospitalier Universitaire St. Pierre, Free University of Brussels, 1000 Brussels, Belgium

2 Division of Endocrinology, Department of Medicine, University of Virginia, Charlottesville, VA 22908

3 International Council for the Control of Iodine Deficiency Disorders, Box 801416, University of Virginia Health System, Charlottesville, VA 22908

aauthor for correspondence: fax 434-243-9195, e-mail jtd@virginia.edu

The first 300 words of the full text of this article appear below.

International groups recommend the following median urinary iodine concentration as the best single indicator of iodine nutrition in populations: severe deficiency, 0–0.15 µmol/L (0–19 µg/L); moderate deficiency, 0.16–0.38 µmol/L (20–49 µg/L); mild deficiency, 0.40–0.78 µmol/L (50–99 µg/L); optimal iodine nutrition, 0.79–1.56 µmol/L (100–199 µg/L); more than adequate iodine intake, 1.57–2.36 µmol/L (200–299 µg/L); and excessive iodine intake, >=2.37 µmol/L (>=300 µg/L) (1). The range in which the median falls is more important than the precise number (2)(3).

Many methods for assessing urinary iodine exist (3)(4)(5)(6)(7)(8), most based on the Sandell–Kolthoff reaction (9), in which iodide catalyzes the reduction of ceric ammonium sulfate (yellow) to the colorless cerous form in the presence of arsenious acid. Although iodide is the chemical form for both the catalytic reaction and in urine, some preliminary treatment is needed to rid urine of impurities, most commonly by acid digestion (3)(5). We have extended previous approaches (5)(6)(10) with improved conditions and here present a new method ("Fast B") that is rapid, inexpensive, reliable, and flexible.

The equipment required for the Fast B method includes a heating block, Pyrex test tubes (13 x 100 mm), two fixed-volume pipettes (0.5 mL and 1.0 mL), one adjustable pipette (0–200 µL), and a multipet (Eppendorf) for quick reagent volume additions of 0.125 and 0.1 mL. The basic chemicals used are potassium iodate, arsenic trioxide, ammonium persulfate, ammonium cerium(IV) sulfate dihydrate, sodium chloride, ferroine, and sulfuric acid.

The solutions used in the assay are as follows:






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2003 by the American Association for Clinical Chemistry.