Evaluation of Elution Behavior of Silver Ions from Silver-Containing Carbonate Hydroxyapatite Composites

Takayuki Murakami; Iwao Noda; Junji Ikeda; Atsushi Nakahira

doi:10.4028/www.scientific.net/KEM.782.72

Paper Titles

Preparation of Calcium Phosphate Glasses Containing Nb₂O₅ and TiO₂
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Cotton-Wool-Like Resorbable Bone Void Fillers Containing β-TCP and Calcium Carbonate Particles
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Synthesis of Spherical Phosphorus-Containing Mesoporous Silica for Improving their Reaction Behavior in Simulated Body Fluid
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Apatite-Forming Ability of Hydrophobicized Cellulose Nanofiber Imparted by Combination with Apatite Nuclei
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Evaluation of Elution Behavior of Silver Ions from Silver-Containing Carbonate Hydroxyapatite Composites
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Bioactivity Assessment of Apatite Nuclei-PVDF Composite Thin Films
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Fabrication of Novel Hemostatic Film with Oxidized Cellulose and Sugar-Containing Hydroxyapatite
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Fabrication of Bioactive Polycaprolactone by Incorporation of Apatite Nuclei
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Fabrication of Hydroxyapatite/Cellulose Fiber Composite with Sheet-Like Structure
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HomeKey Engineering MaterialsKey Engineering Materials Vol. 782Evaluation of Elution Behavior of Silver Ions from...

Evaluation of Elution Behavior of Silver Ions from Silver-Containing Carbonate Hydroxyapatite Composites

Abstract:

Infection related to orthopedic implant surgeries is one of the significant postoperative complications. Recently, many studies have been conducted on silver-containing hydroxyapatite (AgHA) composites as antibacterial and osteoconductive biomaterials to prevent postoperative infection. In this study, we prepared 1 and 10 wt% Ag-containing carbonate hydroxyapatite composites (1AgCHA and 10AgCHA, respectively) by solid-phase reaction, and investigated the relation between the elution rate of Ag ions from the composites and the chemical or physical states of Ag in AgCHA. X-ray diffraction (XRD) and scanning electron microscopy (SEM) results indicated that metallic Ag particles disappeared in 1AgCHA heated at 800°C, whereas they were distributed in 10AgCHA heated at all temperatures. The amount of A-type CO₃^2- group in AgCHA structure drastically increased at 800°C, but decreased with increasing amount of Ag. The lattice constant (a-axis) of hydroxyapatite expanded drastically when heated at 800°C, and with increasing Ag content, the extent of expansion of a-axis decreased as well as amount of A-type CO₃^2- in CHA. Moreover, after the 48-h elution test, the concentration of Ag⁺ released from 10AgCHA heated at 800°C was less than 0.1% of total Ag amounts, while 1AgCHA heated at 800°C released over 0.8% of total Ag amounts. The results indicate that Ag⁺ and CO₃^2- were substituted competitively into the Ca²⁺ and OH^- sites of HA, respectively, after heating at 800°C, and that the elution rate of Ag⁺ from the sites of Ag⁺-substituted CHA was faster than that from metallic Ag particles. A better understating of the elution behavior of Ag from AgCHA is important for controlling the physical and chemical states of Ag in composites.