Degradable biocomposite of nano calcium-deficient hydroxyapatite-multi(amino acid) copolymer

Abstract

Background and methods

A nano calcium-deficient hydroxyapatite (n-CDHA)-multi(amino acid) copolymer (MAC) composite bone substitute biomaterial was prepared using an in situ polymerization method. The composition, structure, and compressive strength of the composite was characterized, and the in vitro degradability in phosphate-buffered solution and preliminary cell responses to the composite were investigated.

Results

The composite comprised n-CDHA and an amide linkage copolymer. The compressive strength of the composite was in the range of 88–129 MPa, varying with the amount of n-CDHA in the MAC (ranging from 10 wt% to 50 wt%). Weight loss from the composite increased (from 32.2 wt% to 44.3 wt%) with increasing n-CDHA content (from 10 wt% to 40 wt%) in the MAC after the composite was soaked in phosphate-buffered solution for 12 weeks. The pH of the soaking medium varied from 6.9 to 7.5. MG-63 cells with an osteogenic phenotype were well adhered and spread on the composite surface. Viability and differentiation increased with time, indicating that the composite had no negative effects on MG-63 cells.

Conclusion

The n-CDHA-MAC composite had good cytocompatibility and has potential to be used as a bone substitute.

Keywords:

• calcium deficient hydroxyapatite
• multi(amino acid) copolymer
• biocomposite
• degradability
• cytocompatibility

Acknowledgments

The authors are grateful for the financial support of the National Natural Science Foundation of China (31070834), the Key Medical Program of Science and Technology Development of Shanghai (09411954900), and the Nano special program of Science and Technology Development of Shanghai (1052nm06600).

Disclosure

The authors report no conflicts of interest in this work.