Influence of precursor deficiency sites for borate incorporation on the structural and biological properties of boronated hydroxyapatite

Gokcekaya O., Ergun C., Webster T. J., Nakano T.

Ceramics International, vol.49, no.5, pp.7506-7514, 2023 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 49 Issue: 5
  • Publication Date: 2023
  • Doi Number: 10.1016/j.ceramint.2022.10.232
  • Journal Name: Ceramics International
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, Chemical Abstracts Core, Communication Abstracts, INSPEC, Metadex, Civil Engineering Abstracts
  • Page Numbers: pp.7506-7514
  • Keywords: Hydroxyapatite, Chemical synthesis, Borate, Incorporation, Osteoblast adhesion, Osteoblast spreading
  • Istanbul Technical University Affiliated: Yes

Abstract

© 2022 The AuthorsThe biological properties of hydroxyapatite (HA) are significantly influenced by its compositional characteristics especially doping elements and/or Ca/P ratio, which can be altered by precursor chemistry. In this study, a group of boronated (B-incorporated) hydroxyapatite (BHA) was synthesized using a precipitation method by setting the Ca/P ratio to the stoichiometric value of HA (1.67), while altering the precursor chemistry by adjusting either (Ca + B)/P (Ca-deficient precursor, BC) or Ca/(P + B) (P-deficient precursor, BP). After heat-treatment, the partial decomposition of the BC was observed, forming tricalcium phosphate as the byproduct, however, the BP showed phase stability at all temperatures. The B-ionic species in the form of (BO2)− and (BO3)3− were incorporated into the HA structure at the (PO4)3− and (OH)− positions, respectively. The incorporation of the B species also facilitated the incorporation of (CO3)2− groups specifically in the BPs. This is the first finding on BHA reporting that preferential (CO3)2− incorporation depends on the precursor chemistry used. As a result, osteoblast adhesion was superior on the BPs compared to pure HA owing to the carbonated structure, increasing cell spreading area. As such, this in vitro study highlighted that the present P-deficient precursor approach for synthesizing BHA improved biocompatibility properties and should, thus, be further considered for the next-generation of improved orthopedic applications.