Characterization of Solution Properties of Four Iron Sources in Model Systems by Solubility Studies and IR/VIS Reflectance Spectrophotometry

摘要

ABSTRACTThe hydrolysis of iron and the effect of aging on the resolubilization of iron hydroxides under simulated gastric pH conditions were measured and spectroscopy was evaluated as a predictor of these changes. Model systems of ferrous sulfate (FeZSO4), ferric sulfate (Fe2(SO4)3), ferric chloride (FeCl3) and hydrogen‐reduced elemental iron (HRFe), with and without ascorbic acid, were analyzed at intervals over 10 wk storage for both soluble iron and iron resolubilized from insoluble iron hydroxide polymers. Irreversible hydrolysis, resulting in polymers with ordered structures, occurred in the FeSO4and HRFe systems. Spectra of air‐dried precipitates correlated with solution behavior of iron providing a possible predictive technique. Added ascorbic acid increased the levels of soluble iron in all syst