It is of significance to further improve the bioactivity of existing calcium phosphate (Ca–P) biomaterials to satisfy the needs of regenerative medicine. Due to its compositional similarity to natural bone mineral, calcium-deficient hydroxyapatite (CDHA) is supposed to possess excellent bioactivity. However, it is difficult to fabricate Ca–P ceramics with a high amount of CDHA, as CDHA is easy to decompose during the sintering process. The present study introduced an effective approach to stabilize CDHA in biphasic calcium phosphate (BCP) ceramics by adding alginate, and investigated the roles of CDHA in their biological performances. The characterization of the phase composition, crystal structure, and functional group demonstrated that the addition of alginate could obviously inhibit CDHA decomposition to attain novel BCP ceramics with a high CDHA content (BCP-A), which could better mimic the inorganic composition of natural bones as compared with the conventional BCP ones (BCP-C). In vitro studies suggested BCP-A showed better bioactivity and osteoinductive capacity than BCP-C, as evidenced by the increased serum protein adsorption, better bone-like apatite formation and cell spreading, and promoted osteogenic differentiation. In vivo intramuscular implantation further confirmed that BCP-A could induce more ectopic bone formation than BCP-C, suggesting BCP-A had a stronger osteoinductivity. Altogether, this study demonstrates that the stabilization of CDHA in BCP ceramics by adding alginate offers a promising principle for designing regenerative biomaterials to process superior biological performances.

中文翻译：

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通过添加藻酸盐以增强其生物学性能来稳定双相磷酸钙陶瓷中钙缺乏的羟基磷灰石†

进一步提高现有磷酸钙（Ca–P）生物材料的生物活性，以满足再生医学的需求，具有重要意义。由于其与天然骨矿物质的组成相似性，缺钙羟基磷灰石（CDHA）被认为具有出色的生物活性。但是，很难制造出具有大量CDHA的Ca-P陶瓷，因为CDHA在烧结过程中很容易分解。本研究介绍了一种通过添加藻酸盐来稳定双相磷酸钙（BCP）陶瓷中CDHA的有效方法，并研究了CDHA在其生物学性能中的作用。相组成，晶体结构，体外研究表明，BCP-A具有比BCP-C更好的生物活性和骨诱导能力，这可以通过增加血清蛋白吸附，更好的骨样磷灰石形成和细胞扩散以及促进成骨分化来证明。体内肌肉内植入进一步证实，BCP-A比BCP-C可以诱导更多的异位骨形成，表明BCP-A具有更强的骨诱导能力。总之，这项研究表明，通过添加藻酸盐来稳定BCP陶瓷中CDHA的含量为设计可再生生物材料以处理优异的生物学性能提供了有希望的原则。