A Comparative Study Between Feed Iodine And Urine Iodine In Iodine Deficiency Of Rat Models

Objective: To analyze the differences between the various methods of low iodine diet and iodine deficiency rat urine iodine content determination, combined with the uncertainty of quantitative chemical analysis, assessment to determine the appropriate method of feed, measured urinary iodine iodine deficiency in rats modeling.Methods: A Comparative Analysis of iodine content determination method detection limit of the standard curve between GB Meal(feed) iodine, urinary iodine determination method and other methods of the same sample(feed, urine) correlation, recovery, precision / accuracy recoveries, the wavelength difference between the measured. Combining different methods of quantitative chemical analysis to determine the feed Uncertainty iodine, urinary iodine measurement requirements and test methods at suitable conditions were analyzed.Results:1. Feed iodine iodine deficiency in rats modeling(1) Detection limit: arsenic cerium catalytic spectrophotometry and iron thiocyanate colorimetry reduction of sodium nitrite mean were 1.7μg / L of iodine and 1.1μg /L iodine.(2) Standard curve: sodium nitrite reduction ironthiocyanate colorimetric standard concentration was 0~100μg/L, | r | = 0.9997. Arsenic cerium catalytic spectrophotometry was 0~300μg/L, | r | = 0.9994.(3) Precision and Recovery: arsenic cerium catalytic spectrophotometry reproducible precision of 0.10,95% confidence level of the maximum permissible error of 0.28, the measured recovery was 111.8%. Sodium nitrite reduction assay precision of 0.05, the error is 0.14, the measured recovery was 96.8%.(4) Measurement of wavelength: arsenic cerium catalytic spectrophotometric measurement were wavelength 510 nm, 460 nm wavelength colorimetry sodium nitrite reduction when there is a better assay sensitivity and linear range of determination of iodine.2. Modeling urinary iodine iodine deficiency in rats(1) Detection limit: GB method detection limit and ammonium sulfate were 1.6μg/L of iodine and 2.9μg / L iodine.(2) Standard curve Dependency: ammonium persulfate concentration method was 0~300μg / L while the correlation coefficient r = 0.9993~0.9997 and average r = 0.9994. National standard method the correlation coefficient r = 0.9992~0.9998 and average r = 0.9995.(3) Recovery and 95% confidence limits range: GB method recoveries for 95.6%~98.5% ammonium persulfate 108.4%~114.6% law.(4) Precision/Accuracy: urine test concentration select 50~100μg/L, after the standard solution to take maximum concentration of 0.9 times were calculated, 0.7 GB method precision was better than ammonium persulfate law 1.4. GB maximum permissible error of law was also significantly less than the 2.1ammonium persulfate law 4.0.(5) Recoveries: GB had an average recovery rate 97.8%, ammonium persulfate method 112.3%.(6) Measurement of wavelength: 405 nm measurement wavelength national standard method, ammonium persulfate law 420 nm wavelength when you can get a better assay sensitivity and linear range of determination of iodine.(7) Uncertainty: Uncertainty of the national standard method for 1.82μg/L, later expanded uncertainty 4.55μg/L. Uncertainty of ammonium persulfate 1.98μg/L, later extended uncertainty 5.65μg/L.Conclusion:1. Feed iodine iodine deficiency in rats modeling(1) Detection limit: sodium nitrite reduction colorimetric detection limit of greater than arsenic cerium spectroscopy.(2) Standard curve Dependency: nitrite and arsenic reduction colorimetric cerium spectroscopy have good linear correlation.(3) Recovery and 95% confidence limit of the range: the measured nitrite reduction to meet the expectations of recovery, interference factors and standard deviation of arsenic cerium spectroscopy.(4) Precision/Accuracy: urine test concentration select 50~100μg/L, after the standard solution to take maximum concentration of 0.9 times the whole program detects nitrite method precision and the maximum error is better than arsenic cerium spectroscopy.(5) Recoveries: nitrous percent recovery method is relatively high.2. Modeling urinary iodine iodine deficiency in rats(1) Detection limit: the national standard method detection range bigger.(2) Standard curve Dependency: ammonium persulfate law and national standard method is similar as well as there is a good linear relationship.(3) Recovery and 95% confidence limits range: Found recoveries national standard method to meet the expected range of 95%~105% ammonium persulfate law because of the presence of confounding factors and standard deviation range exceeded expectations is worth.(4) Precision/accuracy: urine test concentration select 50 ~100μg/L, after the standard solution to take maximum concentration of 0.9 times the whole program detects precision GB method is better, the maximum error value is small.(5) Recoveries: average percent recovery of the national standard method is high.(6) Uncertainty: Uncertainty is less than the national standard ammonium persulfate method, To find the accurate measurement, we recommend that ammonium persulfate some technical measures to use the law in the determination process.