title: Heme Iron Release from Alginate Beads at In Vitro Simulated Gastrointestinal Conditions.
abstract: Heme iron (Fe) release from alginate beads at in vitro simulated gastrointestinal conditions for potential use as oral heme Fe supplement was studied. Five beads at different ratios of sodium alginate (SA)-to-spray-dried bovine blood cells (SDBC) with weight ratios of 1:1.25, 1:2.5, 1:5, 1:10, and 1:15 (w/w) were prepared. Release characteristics of these beads were investigated at in vitro simulated gastrointestinal conditions. Release media pH strongly influenced the controlled Fe release from the beads. The heme Fe-beads in simulated gastric fluid (pH 2) remained in a shrinkage state and Fe release was low: 25.8, 21.1, 11.6, 12.1, and 12.0 % for 1:1.25, 1:2.5, 1:5, 1:10, and 1:15 ratios, respectively. Proportion and amount of Fe released by 1:1.25 and 1:2.5 ratios was higher than the other ratios. The heme Fe-beads swelled and dissociated in simulated intestinal fluid (pH 6), releasing three-fourths of the Fe in 200 min. The morphology studies showed that Fe release followed formation of pores in the alginate matrix, generating erosion of the beads and complete disintegration after 75 and 200 min of gastric and intestinal incubation, respectively. These results indicate that heme Fe-beads may be useful for oral delivery of heme Fe supplement.
authors.affiliation: Faculty of Veterinary and Animal Sciences, University of Chile, Santa Rosa, 11.735, La Pintana, Santiago, Chile. cvalenzuelav@u.uchile.cl.
authors.forename: Carolina
authors.initials: C
authors.lastname: Valenzuela
authors.affiliation: Faculty of Veterinary and Animal Sciences, University of Chile, Santa Rosa, 11.735, La Pintana, Santiago, Chile.
authors.forename: Valesca
authors.initials: V
authors.lastname: Hernández
authors.affiliation: Faculty of Veterinary and Animal Sciences, University of Chile, Santa Rosa, 11.735, La Pintana, Santiago, Chile.
authors.forename: María Sol
authors.initials: MS
authors.lastname: Morales
authors.affiliation: Micronutrients Laboratory, Institute of Nutrition and Food Technology (INTA), University of Chile, Avda. El Libano, 5524, Santiago, Chile.
authors.forename: Fernando
authors.initials: F
authors.lastname: Pizarro
mesh_terms: D000464:Alginates / Q000737:chemistry*; D000818:Animals; D001773:Blood Cells; D002417:Cattle; D005750:Gastric Juice / Q000737:chemistry* / Q000378:metabolism; D020723:Glucuronic Acid / Q000737:chemistry; D006418:Heme / Q000032:analysis* / Q000737:chemistry*; D006603:Hexuronic Acids / Q000737:chemistry; D066298:In Vitro Techniques; D007501:Iron / Q000032:analysis* / Q000737:chemistry*; D008863:Microspheres
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D006418:Heme; D020723:Glucuronic Acid; D007501:Iron
keywords: Alginate beads; Gastrointestinal conditions; Heme iron; Release