title: The effect of Ca/P concentration and temperature of simulated body fluid on the growth of hydroxyapatite coating on alkali-treated 316L stainless steel.
abstract: 316L-SS is one of the important materials both in orthopaedics and dentistry for bone screw/plate, intra-medullary rod, fixation wire, HIP joint, and knee joint. However, the biocompatibility and bone-bonding ability troubled researches for years. In the study, a simple chemical method was tried so as to establish and induce a bioactive HA layer on the surface of 316L stainless steel. When the metallic substrates treated with 10 M NaOH aqueous solution and subsequently heated at 600 degrees C, a thin sodium chromium oxide layer was formed on the surfaces as the linking layer for HA and 316L-SS. After 316L-SS treated with alkali solution, it would soak into a simulated body fluid with higher concentration of calcium and phosphorous ions to increase the possibility of nucleation of HA. However, the iron oxide and iron chromium oxides were formed on the surface when calcium and phosphorous ions increased. This resulted in loosening the HA layer. When the alkali-treated 316L-SS was soaked into SBF at a temperature of 80 degrees C, it could form a dense and uniform bone-like hydroxyapatite layer on the surface. In the research, the mechanism of the formation of sodium chromium oxide and HA would also be described by the analysis of X-ray diffractometer, scanning electron microscope, energy-dispersion spectrophotometer, and Fourier transformation infrared.
authors.affiliation: Institute of Biomedical Engineering, National Taiwan University, Taipei.
authors.forename: Feng-Huei
authors.initials: FH
authors.lastname: Lin
authors.forename: Yao-Shan
authors.initials: YS
authors.lastname: Hsu
authors.forename: Shih-Hsun
authors.initials: SH
authors.lastname: Lin
authors.forename: Jui-Sheng
authors.initials: JS
authors.lastname: Sun
mesh_terms: D000468:Alkalies / Q000494:pharmacology; D001672:Biocompatible Materials; D001769:Blood / Q000378:metabolism; D002118:Calcium / Q000737:chemistry*; D017608:Chromium Compounds / Q000737:chemistry; D017886:Durapatite / Q000737:chemistry*; D005290:Ferric Compounds / Q000737:chemistry; D006801:Humans; D007477:Ions; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D008956:Models, Chemical; D010758:Phosphorus / Q000737:chemistry*; D013053:Spectrophotometry; D017550:Spectroscopy, Fourier Transform Infrared; D013193:Stainless Steel; D013696:Temperature; D013997:Time Factors; D014961:X-Ray Diffraction
chemical_list: D000468:Alkalies; D001672:Biocompatible Materials; D017608:Chromium Compounds; D005290:Ferric Compounds; D007477:Ions; D013193:Stainless Steel; C000499:ferric oxide; D010758:Phosphorus; D017886:Durapatite; D002118:Calcium; C023600:chromic oxide