title: Biomineralization of nanoscale single crystal hydroxyapatite.
abstract: The chemical and physical characteristics of nanocrystalline hydroxyapatite particles which formed during the subcutaneous implantation of crab shell in Sprague-Dawley rats were studied using selected area electron diffraction (SAED) and high resolution transmission electron microscopy (HRTEM). The initial SAED characterization evidence indicated the presence of an amorphous calcium phosphate phase. The electron dense nanophase particles which formed in the wound healing zone displayed broad diffuse rings which usually indicate a low crystalline order or amorphous phase. High resolution transmission electron microscopy (HRTEM) revealed that these mineralized regions contained discrete single crystal particles less than 5nm in size. Micrographs taken at successively higher magnifications revealed very small nanoparticles with a hexagonal arrangement of ion channels with characteristic spacing of 0.54nm and 0.23nm. This study revealed that single crystal hydroxyapatite nanoparticles consisting of only a few unit cells formed via a biomineralization directed process.
authors.affiliation: Catholic University of America, BONE/CRAB Lab, Department of Biomedical Engineering, Washington, DC 20064, United States.
authors.forename: Tiffany
authors.initials: T
authors.lastname: Omokanwaye
authors.affiliation: Catholic University of America, BONE/CRAB Lab, Department of Biomedical Engineering, Washington, DC 20064, United States. Electronic address: wilsono@cua.edu.
authors.forename: Otto C
authors.initials: OC
authors.lastname: Wilson
authors.affiliation: Howard University, Department of Biology, Washington, DC, United States.
authors.forename: Ayelle
authors.initials: A
authors.lastname: Gugssa
authors.affiliation: Howard University, Department of Biology, Washington, DC, United States.
authors.forename: Winston
authors.initials: W
authors.lastname: Anderson
mesh_terms: D000818:Animals; D018786:Bone Substitutes / Q000737:chemistry*; D002113:Calcification, Physiologic / Q000187:drug effects*; D002130:Calcium Phosphates / Q000737:chemistry; D003460:Crystallization / Q000379:methods; D017886:Durapatite / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission / Q000379:methods; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D019736:Prostheses and Implants; D051381:Rats; D017207:Rats, Sprague-Dawley; D014945:Wound Healing / Q000187:drug effects
chemical_list: D018786:Bone Substitutes; D002130:Calcium Phosphates; C519480:amorphous calcium phosphate; D017886:Durapatite
keywords: Biomineralization; High resolution transmission electron microscopy; Hydroxyapatite