Development and characterization of carbonate apatite/β-tricalcium phosphate biphasic cement

- We could make a biphasic CO3Ap/β-TCP cement by using carbonated α-TCP/β-TCP powder.
- Biphasic CO3Ap/β-TCP cement had a self-setting ability.
- Diametral tensile strength of the cement decreased with the carbonation period.
- The mechanical property and composition ratio of CO3Ap could be changed by the treatment time of carbonation.

Biphasic calcium phosphate consisting of carbonate apatite and β-tricalcium phosphate (β-TCP) is an excellent bone substitute with controllable bioresorbability. Fabrication of biphasic calcium phosphate with self-setting ability is expected to enhance the potential of applicability as bone substitute. In this study, mixtures of α-TCP/β-TCP powder after carbonation period 1, 3, and 5 h with 1.0 M NaHCO3 were prepared. These powders were mixed with 0.25 M Na2HPO4 at a P/L ratio of 2, and then hardened at 37 °C and 100% RH up to 24 h. XRD patterns and FT-IR spectrum showed that the resulting hardened cement consisted of biphasic carbonate apatite and β-TCP. Diametral tensile strength of the cement decreased with the carbonation period.