Silver and fluoride doped hydroxyapatites: Investigation by microstructure,mechanical and antibacterial properties

Hydroxyapatite co-doped with Ag⁺ and F^? ions was synthesized by the precipitation method and sintered at 1100 °C for 1 h. Samples were characterized by density, X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, and scanning electron microscopy to investigate their microstructure, phase formation and bonding characteristics. Moreover, samples were also characterized by microhardness and antibacterial tests. Small amount of dopings resulted in high densities and fine grain microstructures. In most of the samples, hydroxyapatite was the main phase with a minor amount of β-TCP. Presence of fluoride and small amount of TCP was verified with all characteristic FTIR bands of hydroxyapatite for most of the samples. Compared to the pure hydroxyapatites, much higher microhardness values were measured in samples co-doped with Ag⁺ and F^? ions. Antibacterial activity of the materials related to Escherichia coli was also observed in hydroxyapatite samples with high amount of Ag⁺ ions.