title: Formation of composites comprised of calcium deficient HAp and cross-linked gelatin.
abstract: Cross-linked gelatin/calcium deficient hydroxyapatite (CDHAp) composites were prepared at or near physiologic temperature. alpha-tricalcium phosphate (alpha-TCP) or a mixture of tetracalcium phosphate and dicalcium phosphate were used as CDHAp precursors. Glutaraldehyde was used to cross-link the gelatin fibers. CDHAp formation reached completion in the presence of cross-linked gelatin fibers. Effects of cross-linking concentrations, proportions of gelatin fiber, molecular weight of gelatin and the temperature of the hydration reaction on the formation of CDHAp were studied. Cross-linked gelatin acts as a nucleating agent for CDHAp formation. The pH variations during CDHAp formation are lower at the onset of the reactions in the presence of cross-linked gelatin fibers. Although cross-linked gelatin fibers enhance CDHAp formation their composites have low mechanical strengths. Swelling of gelatin appears to be a major factor that limits the strengths of the CDHAp/cross-linked gelatin composites.
authors.affiliation: Department of Materials Science and Engineering, Penn State University, Room 136 Materials Research Laboratory, University Park, PA 16802, USA.
authors.forename: Ahmed H
authors.initials: AH
authors.lastname: Touny
authors.forename: Cato
authors.initials: C
authors.lastname: Laurencin
authors.forename: Lakshmi
authors.initials: L
authors.lastname: Nair
authors.forename: Harry
authors.initials: H
authors.lastname: Allcock
authors.forename: Paul W
authors.initials: PW
authors.lastname: Brown
mesh_terms: D001672:Biocompatible Materials / Q000138:chemical synthesis* / Q000737:chemistry; D002118:Calcium / Q000737:chemistry*; D002151:Calorimetry; D019245:Compressive Strength; D003432:Cross-Linking Reagents / Q000737:chemistry*; D017886:Durapatite / Q000138:chemical synthesis* / Q000737:chemistry; D005780:Gelatin / Q000737:chemistry*; D005976:Glutaral / Q000737:chemistry; D008970:Molecular Weight; D012996:Solutions
chemical_list: D001672:Biocompatible Materials; D003432:Cross-Linking Reagents; D012996:Solutions; D005780:Gelatin; D017886:Durapatite; D002118:Calcium; D005976:Glutaral