title: [Preparation of sodium alginate-nanohydroxyapatite composite material for bone repair and its biocompatibility].
abstract: OBJECTIVE
  To prepare sodium alginate-nanohydroxyapatite composite material and to explore its feasibility as a bone repair material.
  
  
  METHODS
  Sodium alginate-nanohydroxyapatite composite material was prepared using chemical cross-linking and freeze-drying technology. The composite was characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM) and its porosity was measured by liquid displacement method. The fifth passage of bone marrow stromal stem cells (BMSCs) were incubated on the composite material and then growth was observed by inverted microscope and SEM. BMSCs were cultured with liquid extracts of the material, methyl thiazolyl tetrazolium (MTT) assay was used to calculate the relative growth rate (RGR) on 1, 3, 5 d and to evaluate the cytotoxicity. Fresh dog blood was added into the liquid extracts to conduct hemolysis test, the spectrophotometer was used to determine the optical density (OD) and to calculate the hemolysis rate.
  
  
  RESULTS
  Sodium alginate-nanohydroxyapatite composite material displayed porosity, the porous pore rate was (88.6 +/- 4.5)%. BMSCs showed full stretching and vigorous growth under inverted microscope and SEM. BMSCs cultured with liquid extracts of the material had good activities. The toxicity of composite material was graded as 1. Hemolysis test results showed that the hemolysis rate of the composite material was 1.28%, thus meeting the requirement of medical biomaterials.
  
  
  CONCLUSIONS
  The composite material fabricated in this study has high porosity and good biocompatibility.
authors.forename: Yanmei
authors.initials: Y
authors.lastname: Wang
authors.forename: Jiacai
authors.initials: J
authors.lastname: He
authors.forename: Quanli
authors.initials: Q
authors.lastname: Li
authors.forename: Jijia
authors.initials: J
authors.lastname: Shen
mesh_terms: D000464:Alginates; D001672:Biocompatible Materials; D002478:Cells, Cultured; D020723:Glucuronic Acid; D006603:Hexuronic Acids; D006801:Humans; D059630:Mesenchymal Stem Cells; D016062:Porosity; D023822:Tissue Engineering; D054457:Tissue Scaffolds
chemical_list: D000464:Alginates; D001672:Biocompatible Materials; D006603:Hexuronic Acids; D020723:Glucuronic Acid