Synthesis of Biocompatible Silver-Doped Carbonate Hydroxyapatite Nanoparticles Using Microwave-Assisted Precipitation and In Vitro Studies for the Prevention of Peri-Implantitis.

A carbonate-hydroxyapatite-based antibacterial implant material with low cytotoxicity was synthesized. The silver ion (Ag) was incorporated into CHA material, resulting in silver-doped carbonate hydroxyapatite (CHA-Ag). The microwave-assisted precipitation method was used to synthesize the CHA-Ag material. The amount of Ag was varied at 0.005, 0.010, and 0.015 mol fractions (χAg). The XRD results showed that the diffractograms corresponded with hydroxyapatite (ICSD 98-05-1414), without any additional phase. The presence of carbonate ions was indicated by vibrations at wavenumber of 871, 1411, and 1466 cm in the infrared spectra. The CHA-Ag materials were agglomerates of nanosized particles with low crystallinity. The particle size and crystallinity of the materials decreased due to the incorporation of CO and Ag. The incorporated Ag successfully inhibited peri-implant-associated bacterial growth. The antibacterial ability increased alongside the increase in the Ag amount. The pre-osteoblast MC3T3E1 cell could grow up to >70% in the MTT assay, despite the use of Ag as a dopant. The cell viability was higher in the CHA-Ag-containing media than in the CHA-containing media. The MTT assay also revealed that the CHA-Ag cytotoxicity decreased even though the Ag amount increased. The CHA-Ag-15 had the lowest cytotoxicity and highest antibacterial activity. Therefore, the optimal amount of Ag in the CHA-Ag formulation was χAg = 0.015.