A “three-in-one” strategy for enhancing osteogenic, angiogenic and antibacterial properties of titanium implants

A three-in-one porous coating was fabricated on an orthopedic Ti surface. • The coating integrated osteogenic, angiogenic, and antibacterial activities. • Simvastatin and Cu 2+ were sustainedly released from the coating. • The coating modulated osteoblast and endothelial cell growth behaviors. • The coating inhibited bacterial adhesion by over 98.53%. To enhance the bioactivity and antimicrobial properties of orthopedic Ti implants, a “three-in-one” coating was well designed and fabricated. A bone-mimicking porous nanofibrous mesh structure (Ti-OH) was first constructed via alkali-heat treatment, followed by sequential biofunctional modifications involving Cu 2+ chelation via phase-transited lysozyme (PTL) (OH-PC) and simvastatin (SV) loading mediated by carboxymethyl-β-cyclodextrin (CM-β-CD) (OH-PCβS). A comprehensive analysis of the as-prepared coatings was conducted using SEM, EDS, XPS, ATR-FTIR, and contact angle measurements. The released concentrations of Cu 2+ and SV were measured with an inductively coupled plasma optical emission spectrometer and a microplate reader, respectively. The angiogenic, osteogenic, and antimicrobial potentials of the coatings were evaluated through cell growth behaviors and antibacterial assays. These results demonstrate that the bone-mimicking porous nanofibrous structure was successfully functionalized with PTL, Cu 2+ , CM-β-CD, and SV. Benefiting from the porous structure and the sustained release of Cu 2+ and SV, the OH-PCβS coating facilitated initial adhesion and proliferation of endothelial cells and osteoblasts, upregulated the expression levels of vascular endothelial growth factor (VEGF), alkaline phosphatase (ALP), osteocalcin (OCN) and runt-related transcription factor 2 (RUNX2), and accelerated biomineralization in osteoblasts. The OH-PCβS coating was demonstrated to possess excellent pro-angiogenic and pro-osteogenic bioactivity. Additionally, the OH-PCβS coating exhibited remarkable antibacterial properties toward S. aureus and E. coli (99.31% and 98.53% inhibition, respectively), owing to the release of Cu 2+ . The OH-PCβS coating developed in this study provides a “three-in-one” strategy for improving the long-term survival of orthopedic Ti implants by integrating angiogenic, osteogenic, and antibacterial functions. Download: Download high-res image (115KB) Download: Download full-size image