Comparison of Two Methods for the Detection of Urinary Iodine Used in Epidemiological Studies
-
Christian Wuethrich
Abstract
Two methods for the determination of iodine in urine or serum based on the Sandell-Kolthoff reaction were compared. The first was an autoanalyser method (AAII, Technicon) where the mineralisation takes place in a continuous flow manner. This procedure was used at the Department of Clinical Chemistry of the University Hospital of Berne (Switzerland) from 1968 until 1993. The second method was evaluated and adapted in our own laboratory. Each sample and the iodate-standards are mineralised in a Pyrex glass tube and the decolorisation reaction takes place in a 96-well-microtiter plate which was read by a PC-controlled photometer at 405 nm. This method, with a detection limit of 0.1 μmol/l showed good analytical recovery (90 to 110%) and a low imprecision (intra-assay coefficient of variation (CV) of 5% and an inter-assay CV of 7.5%). In contrast to the autoanalyser method, the microtiter plate-method is suitable both for series up to 24 samples (3-fold) and for single samples. A comparison of 87 samples in the range of 0.1 to 60 μmol/l which were measured with both Sandell-Kolthoff based methods showed no obvious discrepancy.
These two methods showed a good agreement for the determination of urinary iodine. This guarantees that the results of earlier epidemiological studies can be compared with recent studies performed in our and many other laboratories.
Copyright (c) 2000 by Walter de Gruyter GmbH & Co. KG
Articles in the same Issue
- Genetic Polymorphisms and Activity of Cholesterol Ester Transfer Protein (CETP): Should We Be Measuring Them?
- Detection of Haemoglobins with Abnormal Oxygen Affinity by Single Blood Gas Analysis and 2,3-Diphosphoglycerate Measurement
- Effect of Acute Phase Response on Cumulative Troponin T Release
- Measurement of Water Turnover Using Deuterium Dilution: Impact of Periodically Varying Turnover Rates on Precision and Accuracy
- Personal Experience with the Application of Carbohydrate-Deficient Transferrin (CDT) Assays to the Detection of Congenital Disorders of Glycosylation
- The Efficacy of Hormone Assays in the Differential Diagnosis of Amenorrhea and Menopause
- Screening for Proteinuria in Japanese Schoolchildren: a New Approach
- Determination of a Redox Compensation Index and Its Relationships to Glycaemic Control in Type 2 Diabetes Mellitus
- Clinical Experiences with a New Semi-Quantitative Solid Phase Immunoassay for Rapid Measurement of Procalcitonin
- Inter-Method Differences and Commutability of Control Materials for HbA2 Measurement
- High Sensitivity C-Reactive Protein: Biological Variations and Reference Limits
- A Model for a Multicentre Approach to the Derivation of Reference Intervals for Thyroid Hormones and Testosterone for Laboratories Using Identical Analysers
- Evaluating Agreement between Two Analytical Methods in Clinical Chemistry
- Comparison of Two Methods for the Detection of Urinary Iodine Used in Epidemiological Studies
- Evaluation of Two Automated Enzyme Immunoassays for Detection of Antinuclear Antibodies
- Performance Evaluation of Nine Hormone Assays on the Immulite 2000®Immunoassay System
- Evaluation of the Clinical Chemistry Analyser Olympus AU400
- Effects of Vitamin E and Selenium on Lipid Peroxidation and Antioxidant Enzymes in Colon of Methylazoxymethanol Treated Rats
- C-Reactive Protein as Cardiovascular Risk Factor A Discovery by ECAT
- Usefulness of EC4 Essential Criteria for Quality Systems of Medical Laboratories as Guideline to the ISO 15189 and ISO 17025 Documents
- Recommendations for Measurement of and Conventions for Reporting Sodium and Potassium by Ion-Selective Electrodes in Undiluted Serum, Plasma or Whole Blood
- IFCC News
- Atlas of Clinical Haematology, by H. Löffler and J. Rastetter
- Introduction to Clinical Nutrition, by Vishwanath M. Sardesai
- Biochemical Composition and Electrolyte Balance of Unstimulated Whole Human Saliva
Articles in the same Issue
- Genetic Polymorphisms and Activity of Cholesterol Ester Transfer Protein (CETP): Should We Be Measuring Them?
- Detection of Haemoglobins with Abnormal Oxygen Affinity by Single Blood Gas Analysis and 2,3-Diphosphoglycerate Measurement
- Effect of Acute Phase Response on Cumulative Troponin T Release
- Measurement of Water Turnover Using Deuterium Dilution: Impact of Periodically Varying Turnover Rates on Precision and Accuracy
- Personal Experience with the Application of Carbohydrate-Deficient Transferrin (CDT) Assays to the Detection of Congenital Disorders of Glycosylation
- The Efficacy of Hormone Assays in the Differential Diagnosis of Amenorrhea and Menopause
- Screening for Proteinuria in Japanese Schoolchildren: a New Approach
- Determination of a Redox Compensation Index and Its Relationships to Glycaemic Control in Type 2 Diabetes Mellitus
- Clinical Experiences with a New Semi-Quantitative Solid Phase Immunoassay for Rapid Measurement of Procalcitonin
- Inter-Method Differences and Commutability of Control Materials for HbA2 Measurement
- High Sensitivity C-Reactive Protein: Biological Variations and Reference Limits
- A Model for a Multicentre Approach to the Derivation of Reference Intervals for Thyroid Hormones and Testosterone for Laboratories Using Identical Analysers
- Evaluating Agreement between Two Analytical Methods in Clinical Chemistry
- Comparison of Two Methods for the Detection of Urinary Iodine Used in Epidemiological Studies
- Evaluation of Two Automated Enzyme Immunoassays for Detection of Antinuclear Antibodies
- Performance Evaluation of Nine Hormone Assays on the Immulite 2000®Immunoassay System
- Evaluation of the Clinical Chemistry Analyser Olympus AU400
- Effects of Vitamin E and Selenium on Lipid Peroxidation and Antioxidant Enzymes in Colon of Methylazoxymethanol Treated Rats
- C-Reactive Protein as Cardiovascular Risk Factor A Discovery by ECAT
- Usefulness of EC4 Essential Criteria for Quality Systems of Medical Laboratories as Guideline to the ISO 15189 and ISO 17025 Documents
- Recommendations for Measurement of and Conventions for Reporting Sodium and Potassium by Ion-Selective Electrodes in Undiluted Serum, Plasma or Whole Blood
- IFCC News
- Atlas of Clinical Haematology, by H. Löffler and J. Rastetter
- Introduction to Clinical Nutrition, by Vishwanath M. Sardesai
- Biochemical Composition and Electrolyte Balance of Unstimulated Whole Human Saliva
