Enhanced bone regeneration with curcumin incorporated and Sr-substituted biphasic calcium phosphate ceramics: Synthesis, characterisation and biomedical applications

Biphasic calcium phosphate (BCP) ceramics are prevalent bone substitutes owing to their potential to accelerate bone development. However, improving the degradation ability and the osteoinductive properties of implantable bone filler BCP ceramics is technically challenging. The incorporation of strontium (Sr) into BCP can substantially improve the regeneration process, due to the distinct mode of action displayed by Sr, which concurrently enhances osteoblastogenesiswhile inhibiting osteoclastogenesis. The Sr-incorporated BCP samples were synthesised by aqueous precipitation process and the produced specimen was dip coated with curcumin to enhance the bactericidal impact of the composite. The specimens were characterised physically and biologically to evaluate their phase composition, wettability, biodegradation as well as responses towards biocompatibility, osteogenicity and antibacterial characteristics. According to the XRD data, the hydroxyapatite (HA)-crystals of Sr-doped BCP were partly converted to the β-tricalcium phosphate (β-TCP) phase after sintering at high temperatures. This came about as the Sr²⁺ partially substituted the Ca²⁺ , and as a result, Ca-deficient HA was synthesised. Antibacterial assay of the synthesized composites demonstrated inhibitory action against S. Aureus bacteria, whereas cell culture using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide) assay exhibited enhanced cell proliferation.