Dual-functional titanium implants via polydopamine-mediated lithium and copper co-incorporation: synergistic enhancement of osseointegration and antibacterial efficacy

作者：Jun Li, Bo Jiang, Liu Yang, Pu Zhang, J. Wu, Yalan Yang, Yan Yang, Guiling Wang, Jie Chen, Ling Zhang, Shiqin Huang, Lingli Zhang, En Zhang · 发表于：Frontiers in Bioengineering and Biotechnology · 年份：2025 · DOI：10.3389/fbioe.2025.1593545 · 被引用次数：3 · 研究领域：Bone Tissue Engineering Materials、Polymer Surface Interaction Studies、Orthopaedic implants and arthroplasty

Introduction Orthopedic implant failure due to inadequate osseointegration and infection remains a critical challenge. To address this, we engineered a polydopamine (PDA)-mediated dual-functional platform for lithium (Li + ) and copper (Cu 2+ ) co-incorporation on titanium alloy (Ti6Al4V) implants, aiming to synergize osteogenic and antibacterial properties through a scalable surface modification strategy. Methods PDA coatings were polymerized onto polished Ti64 substrates, followed by sequential immersion in LiCl (800 μM) and CuCl 2 (10 μM) solutions to construct Li + /Cu 2+ co-doped surfaces (PDA@Li 800-Cu 10). In vitro assays assessed MC3T3-E1 pre-osteoblast proliferation (CCK-8), osteogenic differentiation (ALP activity, RT-PCR for ALP/Axin2 ), and antibacterial activity against S. aureus and E. coli (live/dead staining, CFU assays). In vivo efficacy was evaluated in a rat femoral defect model via micro-CT and histology. Results and discussion Li + -functionalized surfaces (PDA@Li 800) enhanced osteoblast proliferation and osteogenesis via Wnt/β-catenin activation. Cu 2+ -loaded coatings (PDA@Cu 10) eradicated >99% bacteria but moderately suppressed osteogenic markers. The dual-doped PDA@Li 800-Cu 10 surface resolved this bioactivity conflict, maintaining antibacterial efficacy comparable to PDA@Cu 10 while elevating the osteogenic capacity of Cu 2+ -only modified surfaces. In vivo, dual-modified implants eliminated bacterial colonization within 72 h and significan...