Iron surface functionalization system - Iron oxide nanostructured arrays with polycaprolactone coatings: Biodegradation, cytocompatibility, and drug release behavior

Abstract

Abstract A surface functionalization system targeted for iron-based materials is developed by combining two biodegradable components, iron oxide nanostructured arrays and polycaprolactone (PCL) coatings. Iron oxide nanoporous and nanotubular arrays are superior surface functionalization matrices, while their stability and cytocompatibility can be further improved by PCL coatings, the morphology of which can modify the drug release behavior. The biodegradation behavior of this system was investigated firstly by electrochemical tests, and further biodegradation information (including the surface morphology and chemical composition) was collected from samples used in a long-term in vitro cytocompatibility test over 21 days of incubation with human adipose-derived stem cells (ADSCs). Moreover, the drug release behavior of these arrays coated with various PCL coatings was studied using tetracycline as a model drug. Experimental results demonstrate that PCL coatings can endow iron oxide nanostructured arrays a proper biodegradation behavior with bioactive degradation products on the surface, also leading to high cytocompatibility characterized by the production of collagen type I and cell distribution on the PCL-coated samples. Furthermore, with the barrier effect of PCL, the whole functionalization system shows sustainable drug release behavior.