US EPA

1351158 

Journal Article 

Spectrophotometric determination of urinary iodine by flow injection analysis with on-line catalytic digestion 

Zhang, YP; Yuan, DX; Chen, JX; Lan, TS; Chen, HQ 

1996 

Yes 

Clinical Chemistry
ISSN: 0009-9147
EISSN: 1530-8561 

42 

12 

2021-2027 

English 

8969643 

WOS:A1996VX38200021 

http://www.clinchem.org/content/42/12/2021.short
Exit
 

A flow-injection technique involving on-line catalytic digestion and spectrophotometric detection has been developed for the determination of iodine in urine. After urine samples are digested by KMnO4-K2Cr2O7-H2SO4 solution, the iodine in the urine catalyzes the reaction of As(III) with Ce(IV). The remaining Ce(IV) is then reacted with brucine and the product is detected with a spectrophotometer at 480 nm. With this technique, we obtained a detection limit for urinary iodine of 0.039 mumol/L, and the linear range was 0.039-7.88 mumol/L with a CV < 3%. Analytical recovery ranged between 92% and 104% (mean 99%). The sampling frequency of the flow-injection technique was 70/h. We applied the method to measure the iodine concentration in a freeze-dried urine reference sample and in collected urine samples, and compared the results with those obtained by the accepted alkaline ashing technique. The proposed technique has the advantages of being simple, rapid, precise, accurate, and sensitive. It can be used to assess iodine-deficient populations as well as those receiving treatment. 

brucine; iodine deficiency; monitoring therapy; urine; arsenic; cesium