Cerium-oxide functionalized iron scaffolds: A synergistic approach for enhanced degradation and reduced cytotoxicity

Abstract

Biodegradable scaffolds play a crucial role in biomedical restoration. These are three-dimensional (3D) structures that can provide support for the development of newly formed bone tissues. Among the studied metallic biodegradable scaffolds, those composed of iron (Fe) are notable for their high mechanical resistance. However, the slow degradation rate of Fe and the potential cytotoxicity of its degradation products pose challenges to effective osseointegration. Cerium oxide was incorporated into Fe scaffolds to overcome these two inherent limitations.We employed the dynamic hydrogen bubbling template (DHBT) technique, utilizing a citric acid-based electrolyte, to produce iron scaffolds. This same technique was used to embed cerium oxide nanoparticles (CNFe), whereas electrodeposition was used to create a thin cerium oxide coating over the scaffolds (CCFe). The oxidation state of cerium oxide in the functionalized scaffolds was scrutinized through surface characterization techniques. Ensuring similar porosities, we evaluated the degradation of the different distinct scaffolds using electrochemical techniques.The impact of cerium incorporation within or over the scaffolds on their degradation and cell viability was correlated with cerium oxidation states and the nature of the resulting degradation products. The synergistic implications of adding cerium to the iron scaffolds were thoroughly explored, and their potential benefits in future clinical settings were discussed.