title: The effect of change in pH on the solubility of iron bis-glycinate chelate and other iron compounds.
abstract: The effect of a pH change from 2 to 6 was tested on the solubility of ferrous sulfate, ferrous fumarate, iron bis-glycine chelate (Ferrochel) and sodium-iron ethylenediaminetetraacetic acid (NaFeEDTA). It was found that at pH 2 ferrous sulfate, Ferrochel and NaFeEDTA were completely soluble and only 75% of iron from ferrous fumarate was soluble. When pH was raised to 6, iron from amino acid chelate and NaFeEDTA remained completely soluble while solubility from ferrous sulfate and ferrous fumarate decreased 64 and 74%, respectively compared to the amount of iron initially soluble at pH 2. These results suggest that iron solubility from iron bis-glycine chelate and NaFeEDTA is not affected by pH changes within the ranges tested, probably because iron remained associated to the respective compounds.
authors.affiliation: Instituto Venezolano de Investigaciones Científicas (IVIC), Centro de Medicina Experimental, Laboratorio de Fisiopatología-Caracas, Venezuela.
authors.forename: M N
authors.initials: MN
authors.lastname: García-Casal
authors.forename: M
authors.initials: M
authors.lastname: Layrisse
mesh_terms: D004492:Edetic Acid / Q000737:chemistry; D005290:Ferric Compounds / Q000737:chemistry; D005296:Ferrous Compounds / Q000737:chemistry; D005527:Food, Fortified; D005650:Fumarates / Q000737:chemistry; D005998:Glycine / Q000031:analogs & derivatives* / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007502:Iron Chelating Agents / Q000737:chemistry; D058085:Iron Compounds / Q000737:chemistry*; D012995:Solubility
chemical_list: D005290:Ferric Compounds; D005296:Ferrous Compounds; D005650:Fumarates; D007502:Iron Chelating Agents; D058085:Iron Compounds; C073588:bis-glycino iron II; C020748:ferrous sulfate; D004492:Edetic Acid; C019179:Fe(III)-EDTA; D005998:Glycine