Nanosized Silk-Magnesium Complexes for Tissue Regeneration.

Metal ions provide multifunctional signals for cell and tissue functions, including regeneration. Inspired by metal-organic frameworks (MOFs), nanosized silk protein aggregates with a high negative charge density were used to form stable silk-magnesium ion complexes. Magnesium ions (Mg ions) were added directly to silk nanoparticle solutions, inducing gelation through the formation of silk-Mg coordination complexes. The Mg ions released slowly from the nanoparticles through diffusion, with sustained release via tuning the degradation or dissolution of the nanosized silk aggregates. Studies in vitro revealed a dose-dependent influence of Mg ions on angiogenic and anti-inflammatory functions. Silk-Mg ion complexes in the form of hydrogels also stimulated tissue regeneration with a reduced formation of scar tissue in vivo, suggesting potential utility in tissue regeneration. This article is protected by copyright. All rights reserved.