A core-shell structured VEGF-SiO₂@ZnO nanorod array for enhancing osteogenesis performance of Zn-based implants

Area of Science:

• Biomaterials Science
• Nanotechnology
• Orthopedic Implants

Background:

• Zn-based implants release excessive Zn2+ ions, causing cytotoxicity and hindering osteogenesis.
• Degradation of Zn-based implants is a significant challenge for their clinical application.

Purpose of the Study:

• To develop a core-shell nanorod array coating to mitigate Zn-based implant degradation.
• To enhance early osteogenesis and angiogenesis for improved biointegration of Zn-1Ca implants.

Main Methods:

• A hybrid process involving hydrothermal treatment, sol-gel, and impregnation was used.
• A core-shell nanorod array of ZnO (core) and VEGF-loaded mesoporous SiO2 (shell) was constructed on a Zn-1Ca substrate.
• In vitro cell studies with bone marrow stromal cells (BMSCs) and HUVECs, and in vivo studies for new bone formation were conducted.

Main Results:

• The ZnO/SiO2 nanorod array coating significantly improved the anti-corrosion properties of the Zn-1Ca substrate.
• The coating promoted BMSC osteogenesis and HUVEC angiogenesis through controlled release of Zn, Si, and VEGF.
• In vivo studies demonstrated enhanced new bone formation on the coated Zn-1Ca implants.

Conclusions:

• The core-shell nanorod array effectively reduces Zn-based implant degradation.
• This nanostructure accelerates early biointegration by enhancing angiogenesis and new bone formation.
• The developed coating offers a promising strategy for improving Zn-based orthopedic implants.