A novel biomimetic approach to synthesize intergrown nanoengineered biphasic calcium phosphate with tunable nHAP/β-TCP composition

Biphasic calcium phosphate (BCP) possesses characteristic beneficial properties of both the Hydroxyapatite (HAP) and β-Tricalcium Phosphate (β-TCP) and demonstrated promising clinical outcomes in the field of bone tissue engineering. Moreover, synthesis of BCP through the mechanical mixing of HAP and β-TCP may leads to the BCP with nonuniform microarchitecture, poor phase integration, inhomogeneous resorption etc. Thus, methods with the ability to control the phase ratio with integrated intimate contact remain a challenge. To overcome the current challenges, we propose a one-pot synthesis for BCP through the generation of amorphous calcium phosphate (ACP) like precursor followed by calcination to generate BCP with a tunable ratio of HAP and β-TCP. This method leverages Ca 2+ ion chelating biopolymers such as casein protein and microwave assistance to facilitate homogeneous nucleation and the formation of micelles saturated with ACP. The synthesized ACP transformed to BCP through calcination at 800 ° C. The HAP/β-TCP ratio, particle size (nanoscale), and bioactivity can be precisely controlled by adjusting the synthesis parameters. The synthesized bioceramics exhibit varying particle sizes, morphologies and bioactivities. Moreover, morphological analysis of HAP, β-TCP and BCP revealed particle sizes of ∼265 nm, ∼560 nm and 228 - 340 nm, respectively. XRD (X-ray diffraction) analysis confirmed BCP formation through incorporation of casein protein (0.25–10%) facilitating BCP with tunable HAP and β-TCP biphasic ratios. The materials demonstrated optimal biocompatibility and effectively promoted the osteogenic differentiation of mesenchymal stem cells. The one-pot synthesized BCP with tuneable HAP/β-TCP ratios and nanoscale particle sizes demonstrated controlled bioactivity and degradation. This streamlined strategy enables controlled biphasic properties and offers improved osteogenic potential for advanced bone tissue regeneration.