Speciation of iron in breast milk and infant formulas whey by size exclusion chromatography-high performance liquid chromatography and electrothermal atomic absorption spectrometry

摘要

Speciation of iron in milk was carried out by high performance liquid chromatography (HPLC) and electrothermal atomic absorption spectrometry (ETAAS).Milk whey was obtained and low molecular weight protein separation was performed by size exclusion chromatography (SEC) with a TSK Gel SW glass guard (Waters)pre-column and a TSK-Gel G2000 glass (Toso Haas) column.After studying wate as a possible mobile phase,this mobile phase was carefully selected in order to afvoid alterations of the sample and to make subsequent iron determination in the protein frafctions easier by ETAAS.The proposed method is sensitive (limit of detection [LOD]and LOQ 1.4 and 4.7#mu#g 1~(-1),respectively)and precise (relative standard deviation [RSD]<10%).Iron is principally found in the proteins of 3 and 76 kDa in breast milk,and it is irregularly distibuted in infaf tnormulas.