Iodine determination milk, infant

Iodine and Se speciation in breast milk provides an example of the use of CE in hyphenated systems with ICP-MS detection. By employing CE, Michalke and colleagues determined selenoaminocids and identified two chemical forms of iodine, I- and thyroxine, which were present in comparable amounts in milk [115-117]. Other authors used SEC and IEC for I speciation in various types of milk and infant formulae (see Table 8.3) and found I- as the main species, with the exception of breast milk and formulae. The latter were found to contain less I than commercial and human milk, and mostly as an unidentified macromolecular compound. 

Sanandez and Szpunar (1999) determined iodine species in milk and infant formulas using SEC-ICP-MS. Iodine species were quantitatively eluted with 30 mM Tris buffer within 40 minutes and detected by ICP MS with a detection limit of 1 rg/l (as I). A systematic study of iodine speciation in milk samples of different animals (cow, goat), humans of different geographic origin (several European... 

Approximately 80% of iodine in human milk is present as L, while, mainly, another six high molecular weight iodine containing molecules (Braetter et al., 1998) account for the remaining 20%. European breast milk samples have been determined to contain 95 + 60 pg/l total iodine. The total iodine content varied depending on the lactation state, and iodine was associated with fat at approximately 30% and 70% of the low molecular weight fraction (Michalke, 2006). A study of iodine species in milk samples obtained from humans from several different European countries and in infant formulas from different manufacturers was carried out by Femandez-Sanchez and Szpunar (Fernandez-Sanchez Szpunar, 1999). The authors also developed a method to determine iodine in human milk and infant formulas using ICP-MS. In the human milk the values found were between 144 + 93.2 pg/ kg, whereas in the infant formulas the values were 53.3 + 19.5 (Fernandez-Sanchez et al., 2007). 

Determination Of Iodine In Human Milk And Infant Formulas. Journal of Trace Elements in Medicine and Biology, Vol.21, Supp.l, pp 10-13, ISSN 0946-672X Fischer, P.W.F., Labbe, M. R. Giroux, A. (1986). Colorimetric determination of total iodine in foods by iodide-catalyzed reduction of Ce+4. J. Assoc. Off. Anal. Chem., Vol.69, No.4, pp 687 - 689, ISSN 0004-5756... 

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