Design and construction of a microporous CO32− -containing HA/β-TCP biphasic ceramic as a novel bone graft material

Abstract Biphasic calcium phosphate (BCP) ceramics, viewed as the first-line therapeutic materials in clinical practice, are still confronted with challenges such as undesirable biocompatibility and bioactivity given their structural and chemical deficiency. In this study, we designed a novel microporous CO 3 2 − -containing BCP ceramic from Salmo salar bone in a CO 2 atmosphere via two-step high-temperature sintering, and its physicochemical properties and biocompatibility were explored. A without CO 3 2 − - BCP bioceramic material prepared in a single gas atmosphere was used as a comparison. The two scaffolds were characterized by x-ray diffraction (XRD), fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM) , measured the size of its porosity and specific surface area by an instrument and in vitro cell experiment was used to test its biocompatibility. Such synthetic strategy endowed the BCP products with increased β -tricalcium phosphate ( β -TCP) percentage from 37.18wt% to 45.3wt% (compared to BCP without CO 3 2 − ), with the CO 3 2 − content calculated to be 1.98wt%, which is close to that in human bone tissue. The amount of CO 3 2 − incorporation, the a-axes of the lattice parameters have decreased significantly from 9.4845 nm to 9.2942 nm by Rietveld structure refinement. Especially, the novel CO 3 2 − containing BCP exhibits a lower degree of crystallinity than that without CO3 2- . In addition, the natural microporosity remarkably increased from 49.6% for BCP without CO 3 2 − to 64.06% for CO 3