title: Photodegradable iron(III) cross-linked alginate gels.
abstract: Biocompatible photoresponsive materials are of interest for targeted drug delivery, tissue engineering, 2D and 3D protein patterning, and other biomedical applications. We prepared light degradable hydrogels using a natural alginate polysaccharide cross-linked with iron(III) cations. The "hard" iron(III) cations used to cross-link the alginate hydrogel were found to undergo facile photoreduction to "soft" iron(II) cations in the presence of millimolar concentrations of sodium lactate. The "soft" iron(II) cations have a decreased ability to cross-link the alginate which results in dissolution of the hydrogel and the formation of a homogeneous solution. The photodegradation is done using long wave UV or visible light at neutral pH. The very mild conditions required for the photodegradation and the high rate at which it occurs suggest applications for iron(III) cross-linked alginate hydrogels as light-controlled biocompatible scaffolds.
authors: Department of Chemistry and Biomolecular Science, Clarkson University, Potsdam, New York 13699-5810, United States.
authors: Remya P
authors: RP
authors: Narayanan
authors: Galina
authors: G
authors: Melman
authors: Nicolas J
authors: NJ
authors: Letourneau
authors: Nicole L
authors: NL
authors: Mendelson
authors: Artem
authors: A
authors: Melman
mesh_terms: D000464:Alginates / Q000737:chemistry*; D001672:Biocompatible Materials / Q000138:chemical synthesis* / Q000737:chemistry / Q000528:radiation effects; D002264:Carboxylic Acids / Q000737:chemistry / Q000528:radiation effects; D002712:Chlorides / Q000737:chemistry*; D003102:Colloids; D056831:Coordination Complexes / Q000138:chemical synthesis* / Q000737:chemistry / Q000528:radiation effects; D005290:Ferric Compounds / Q000737:chemistry*; D005296:Ferrous Compounds / Q000737:chemistry; D020723:Glucuronic Acid / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D020100:Hydrogels / Q000138:chemical synthesis* / Q000737:chemistry / Q000528:radiation effects; D053768:Metal Nanoparticles / Q000737:chemistry; D010084:Oxidation-Reduction; D010782:Photolysis; D019354:Sodium Lactate / Q000737:chemistry; D012996:Solutions; D054457:Tissue Scaffolds; D014466:Ultraviolet Rays
chemical_list: D000464:Alginates; D001672:Biocompatible Materials; D002264:Carboxylic Acids; D002712:Chlorides; D003102:Colloids; D056831:Coordination Complexes; D005290:Ferric Compounds; D005296:Ferrous Compounds; D006603:Hexuronic Acids; D020100:Hydrogels; D012996:Solutions; D006046:Gold; D020723:Glucuronic Acid; C029451:ferrous chloride; D019354:Sodium Lactate; C024555:ferric chloride