Synthesis and Antimicrobial Activity of Silver-Doped Hydroxyapatite Nanoparticles

Abstract

The synthesis of nanosized particles of Ag-doped hydroxyapatite with antibacterial properties is of great interest for the development of new biomedical applications. The aim of this study was the evaluation of Ca10−xAgx(PO4)6(OH)2 nanoparticles (Ag:HAp-NPs) for their antibacterial and antifungal activity. Resistance to antimicrobial agents by pathogenic bacteria has emerged in the recent years and became a major health problem. Here, we report a method for synthesizing Ag doped nanocrystalline hydroxyapatite. A silver-doped nanocrystalline hydroxyapatite was synthesized at 100°C in deionised water. Also, in this paper Ag:HAp-NPs are evaluated for their antimicrobial activity against Gram-positive and Gram-negative bacteria and fungal strains. The specific antimicrobial activity revealed by the qualitative assay is demonstrating that our compounds are interacting differently with the microbial targets, probably due to the differences in the microbial wall structures.

Substituted hydroxyapatites for biomedical applications: A review

“…Moreover, silver-doped calcium phosphate ceramics has an antimicrobial activity comparable to that of an antibiotic treatment [240]. In recent studies reported by Ciobanu et al [241,242], Ag-HA nanoparticles showed great promise as antibacterial agents against both gram-positive and gram-negative bacteria.…”

Cationic and Anionic Substitutions in Hydroxyapatite

“…By FT-IR and XRD analyses, it was demonstrated that Ag + ions substitute for Ca 2+ ions within the apatite lattice [141,161,181,186,187,189,199,[204][205][206]. Indeed, the effective Ag + incorporation within apatite lattice was testified by the identification of CaO, whose formation was ascribed to the oxidation of the free Ca 2+ ions, available in consequence of Ag + substitution for Ca 2+ within apatite lattice, during the thermal treatments [141].…”

“…It has been verified that Ag-HAps show antibacterial action towards bacteria, viruses, and fungi, playing a more efficient bactericidal role on gram-negative bacteria rather than gram-positive bacteria, owing to the different structures of their cell walls [181,186,193,205]. Moreover, Ag-calcium phosphates have shown an antimicrobial activity comparable to that of an antibiotic treatment [204].…”

In vitro evaluation of the biological compatibility and antibacterial activity of a bone substitute material consisting of silver‐doped hydroxyapatite and Bio‐Oss®

“…17,18 In accordance with x 5 0.5 in the chemical DAP) (Aladdin Reagent, China) was dissolved in deionized water; ammonia (Aladdin Reagent, China) was used to regulate the pH of the DAP solution at 10. Then, the DAP solution was titrated into solution 1 at room temperature, after which the sediment was washed repeatedly with deionized water until the pH decreased to 7.…”