Synthesis and cytotoxicity analysis of porous β-TCP/starch bioceramics

The production of porous ceramics for biomedical applications is widely available in the Ceramics industry. In bioceramic applications, interconnected pores are pertinent to increase osteoconductivity and cell proliferation. However, an increase in pore size and the pore amount decrease the mechanical properties. For this reason, pore properties must be precisely controlled. In this study, the effect of a natural pore-forming agent, corn starch addition, and sintering conditions on mechanical properties and biocompatibility was investigated. During mixing, four different starch amounts (1, 3, 5, and 10 wt%) were added to pure beta-tricalcium phosphate (β-TCP) ceramic powders and pressed. Pressed pellets were sintered at 1000, 1100, 1200, and 1300 °C. A scanning electron microscope (SEM) is used to investigate microstructure, texture, pore size, and cell adhesion. The mechanical properties of the β-TCP ceramic parts were further characterized by measuring the density and compressive strength. Cytotoxicity tests were carried out with MTT assays. The optimum mechanical properties were obtained at 1100 °C sintered biocomposites. Although starch starts to burn around 410 °C and analytical results show no presence of starch after the sintering process, biocomposites initially containing 10% starch showed improved cell proliferation. However, a reduction of 59% in compressive strength and a 16% reduction in the density were also recorded. It was observed that 10 wt% starch addition increases cell proliferation by 10% in sintered β-TCP samples. Starch powder additions can be used to increase the cell viability of the material by facilitating the creation of pores, as a low-cost pore-forming agent for porous bone graft and non-load-bearing material in both orthopaedics and maxillofacial applications. Graphical abstract: [Figure not available: see fulltext.]