Magnesium-Sputtered Collagen Nerve Conduits Regulate Magnesium Ion Release to Promote Peripheral Nerve Regeneration

Autologous nerve grafting, the current gold standard for treating peripheral nerve injuries, faces limitations such as limited nerve availability, the need for secondary surgeries, and complications like sensory loss and donor site pain. Developing nerve conduits with bioactive materials offers a promising solution to these challenges, enhancing nerve regeneration. Among these materials, magnesium has gained attention for its excellent biocompatibility, biofunctionality, and neuroprotective properties. However, issues such as rapid corrosion and the need for controlled ion release remain. In this study, we developed a biocompatible, biomimetic, and biofunctional nerve conduit by sputtering magnesium onto collagen sheets, allowing precise control of magnesium ion release. The Mg coating demonstrated excellent biocompatibility and significantly enhanced neurite outgrowth in vitro. We optimized the sputtering process to regulate the concentration and rate of magnesium ion release, while maintaining the softness of the collagen sheets. In a peripheral nerve injury model, the Mg-sputtered nerve conduit promoted early nerve regeneration, sustained axonal growth, functional recovery, and increased Schwann cell presence. This innovative technique shows great potential for significantly improving peripheral nerve regeneration and highlights the promise of magnesium-based bioactive materials in broader medical applications.