Ultra-trace silver-doped hydroxyapatite with non-cytotoxicity and effective antibacterial activity.

Hydroxyapatite (HAp) nanocrystals as the main inorganic component in hard tissue have been extensively studied for bone regeneration and dental implant treatment. However, failure of surgical reconstruction often occurs owing to the lack of effective antibacterial ability of HAp. It is still a challenge to develop artificial HAp with both efficient antibacterial ability and proper biological properties. Herein, a series of ultra-trace Ag-doped HAp nanocrystals have been elaborately prepared with the optimal doping concentration from 0.27 ppm to 2.2 ppm, which present non-cytotoxicity while possess effective bacteria reduction ability. Ultra-trace Ag-doped HAp nanocrystals possess higher protein adsorption than pure HAp nanocrystals due to the trace doping-induced less negative surface potential. The ultra-trace Ag-doped HAp nanocrystals showed effectively antibacterial ability, non-cytotoxicity and enhanced adsorbability that made them ideal materials for various biocompatible and antibacterial applications.