title: Fabrication of hydroxyapatite sponges by dextran sulphate/amino acid templating.
abstract: We report a new template-directed method for the fabrication of hydroxyapatite (HAp) sponges by using amino-acid-coated HAp nanoparticles dispersed within a viscous polysaccharide (dextran sulfate) matrix, and describe the use of these materials for the viability and proliferation of human bone marrow stromal cells. The nanoparticles were prepared in the presence of excess amounts of aspartic acid, alanine or arginine, and subsequently organised into macroporous frameworks with typical pore sizes of 100-200 microm during thermal degradation of the dextran matrix. The sponge macrostructure was influenced by changes in the heating rate and sintering time, as well as the use of different amino acids or variations in dextran functional groups. Biocompatibility testing showed retention of cell viability, production of extracellular matrix and alkaline phosphatase expression, suggesting that it should be possible to exploit this novel fabrication method for potential applications in cartilage or soft tissue engineering.
authors.affiliation: Centre for Organized Matter Chemistry, School of Chemistry, University of Bristol, Bristol BS8 1TS, UK. r.gonzalez-mcquire@bris.ac.uk
authors.forename: Rosanna
authors.initials: R
authors.lastname: Gonzalez-McQuire
authors.forename: David
authors.initials: D
authors.lastname: Green
authors.forename: Dominic
authors.initials: D
authors.lastname: Walsh
authors.forename: Simon
authors.initials: S
authors.lastname: Hall
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Chane-Ching
authors.forename: Richard O C
authors.initials: RO
authors.lastname: Oreffo
authors.forename: Stephen
authors.initials: S
authors.lastname: Mann
mesh_terms: D000409:Alanine / Q000737:chemistry; D000469:Alkaline Phosphatase / Q000737:chemistry; D000596:Amino Acids / Q000737:chemistry; D001120:Arginine / Q000737:chemistry; D001224:Aspartic Acid / Q000737:chemistry; D001672:Biocompatible Materials / Q000737:chemistry*; D001854:Bone Marrow Cells / Q000166:cytology*; D002130:Calcium Phosphates / Q000737:chemistry; D018929:Cell Culture Techniques / Q000379:methods; D002460:Cell Line; D002470:Cell Survival; D002478:Cells, Cultured; D003094:Collagen / Q000737:chemistry; D016264:Dextran Sulfate / Q000737:chemistry*; D003911:Dextrans / Q000737:chemistry; D017886:Durapatite / Q000737:chemistry*; D005109:Extracellular Matrix / Q000378:metabolism; D006358:Hot Temperature; D006801:Humans; D008855:Microscopy, Electron, Scanning; D049329:Nanostructures / Q000737:chemistry*; D011134:Polysaccharides / Q000737:chemistry; D013997:Time Factors; D023822:Tissue Engineering / Q000379:methods
chemical_list: D000596:Amino Acids; D001672:Biocompatible Materials; D002130:Calcium Phosphates; D003911:Dextrans; D011134:Polysaccharides; D001224:Aspartic Acid; D003094:Collagen; D016264:Dextran Sulfate; D017886:Durapatite; D001120:Arginine; C020243:calcium phosphate; D000469:Alkaline Phosphatase; D000409:Alanine