Study on the genotoxicity of HA/ZrO2 composite particles in vitro.

To evaluate the genotoxicity of the HA/ZrO2 composite particles by using the micronucleus test (MNT) in vitro. HA/ZrO2 composite particles prepared by sintering at high temperature and pressure, that used powder of HA and ZrO2 of different proportions, were compared with pure HA particles and pure ZrO2 particles. The effect of the composite particles on cell proliferation of rabbit mesenchymal stem cells, and its the genotoxicity to rabbit mesenchymal stem cells were detected by MNT method. The MTT test showed that both pure HA particles and composite particles which contained HA promoted cell proliferation of rabbit mesenchymal stem cells, while pure ZrO2 particles did not, and there was a significant difference (P<0.05). The MNT test showed no significant difference between the HA group and the negative control group (P>0.05), but a significant difference between the HA group and the positive control group (P<0.05). The difference between the ZrO2 group and the negative control group was significant (P<0.01), while the difference between the ZrO2 group and the positive control group was insignificant (P>0.05). The genotoxicity of the HA/ZrO2 composite particle increased with a higher proportion of ZrO2 and an increase in the concentration of the composite, and the 30 wt.% HA/70% ZrO2 composite with 200 μg/mL concentration showed significant genotoxicity (P<0.01). Crown