Doped tricalcium phosphate bone tissue engineering scaffolds using sucrose as template and microwave sintering: enhancement of mechanical and biological properties

- Random porous TCP scaffolds are prepared by thermal decomposition of sucrose.
- Additives prevents crack formation and enhances osteoinductivity of TCP in vitro.
- Microwave sintering decreases open interconnected porosity of porous TCP scaffolds.
- PCL improves toughness and osteoblastic differentiation of porous TCP scaffolds.

β-tricalcium phosphate (β-TCP) is a widely used biocompatible ceramic in orthopedic and dental applications. However, its osteoinductivity and mechanical properties still require improvements. In this study, porous β-TCP and MgO/ZnO-TCP scaffolds were prepared by the thermal decomposition of sucrose. Crack-free cylindrical scaffolds could only be prepared with the addition of MgO and ZnO due to their stabilization effects. Porous MgO/ZnO-TCP scaffolds with a density of 61.39 ± 0.66%, an estimated pore size of 200 μm and a compressive strength of 24.96 ± 3.07 MPa were prepared by using 25 wt% sucrose after conventional sintering at 1250 °C. Microwave sintering further increased the compressive strength to 37.94 ± 6.70 MPa, but it decreased the open interconnected porosity to 8.74 ± 1.38%. In addition, the incorporation of polycaprolactone (PCL) increased 22.36 ± 3.22% of toughness while maintaining its compressive strength at 25.45 ± 2.21 MPa. Human osteoblast cell line was seeded on scaffolds to evaluate the effects of MgO/ZnO and PCL on the biological property of β-TCP in vitro. Both MgO/ZnO and PCL improved osteoinductivity of β-TCP. PCL also decreased osteoblastic apoptosis due to its particular surface chemistry. This novel porous MgO/ZnO-TCP scaffold with PCL shows improved mechanical and biological properties, which has great potential in bone tissue engineering applications.