Copper-Doped Barium Titanate Coating: A Piezoelectric Match to Natural Bone for Enhanced Osteogenesis

Qiang Wu; Hongyu Chen; Biaohong Huang; Weijin Hu; Yi Wang; Shujun Li; Yushun Tao; Xu Jiang; Kerong Dai; Yilai Jiao; Liao Wang

doi:10.1021/acsami.5c04997

Copper-Doped Barium Titanate Coating: A Piezoelectric Match to Natural Bone for Enhanced Osteogenesis

ACS Appl Mater Interfaces. 2025 Jun 16. doi: 10.1021/acsami.5c04997. Online ahead of print.

Authors

Qiang Wu¹, Hongyu Chen¹, Biaohong Huang², Weijin Hu^{2

3}, Yi Wang⁴, Shujun Li², Yushun Tao¹, Xu Jiang¹, Kerong Dai¹, Yilai Jiao², Liao Wang¹

Affiliations

¹ Shanghai Key Laboratory of Orthopedic Implants, Clinical and Translational Research Center for 3D Printing Technology, Shanghai Frontiers Science Center of Degeneration and Regeneration in Skeletal System, Department of Orthopedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 639 Zhizaoju Road, Shanghai 200011, China.
² Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang, 110016, China.
³ School of Materials Science and Engineering, University of Science and Technology of China, Shenyang 110016, China.
⁴ Department of Orthopaedics, The First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, 210029, China.

PMID: 40523110
DOI: 10.1021/acsami.5c04997

Abstract

Barium titanate (BaTiO₃) is a conventional piezoelectric material, but its biocompatibility is limited. Besides, its piezoelectric property is significantly different from that of natural bone tissue. To address this, we have developed an innovative coating material that mimics the piezoelectric characteristics of natural bone with a d₃₃ coefficient of 7.8 pm/V. The material was fabricated by replacing titanium (Ti) in the BaTiO₃ crystal lattice with copper (Cu), a strategy that not only augments the piezoelectric response but also harnesses the osteogenic potential of Cu. BaCu_xTi_1-xO₃ reveals an enhanced piezoelectric performance and actively promotes the adhesion, proliferation, and differentiation of MC3T3-E1 cells. Moreover, doped Cu modulates osteogenic differentiation through the upregulation of the Wnt4/β-catenin/SP7/Osterix signaling pathway. The synergistical effect caused by piezoelectricity and the biological activity of Cu contributed to promoting bone regeneration in vivo; in particular, H-BaCu_xTi_1-xO₃ led to a 15.6% increase of the bone volume percentage compared to BaTiO₃. Furthermore, H-BaCu_xTi_1-xO₃ promoted the accumulation of bone extracellular matrix components including Osteopontin (OPN) and Collagen Type I (COL-1), which, respectively, increased by 62.12 and 155%. The synergistic interplay between the piezoelectric property of BaCu_xTi_1-xO₃ and the osteogenic influence of Cu has significantly improved the repairing process of bone defects, offering a promising advancement in the field of orthopedic implant coatings.

Keywords: BaTiO3; bone regeneration; copper; piezoelectric effect; synergistic effects.