Magnetic Responsive Carbon Nanotubes Composite Scaffolds for Chondrogenic Tissue Engineering.

The demand for engineered scaffolds capable to deliver multiple cues to the cells continues to grow as the interplay between cell fate with microenvironmental and external cues is revealed. Emphasis has been given to develop stimuli-responsive scaffolds. These scaffolds are designed to sense an external stimulus triggering a specific response (e.g., change in the microenvironment, release therapeutics, etc.) and then initiate/modulate a desired biofunction. Here, magnetic responsive carboxylated multi-walled carbon nanotubes (cMWCNTs) are integrated into 3D collagen/PLA scaffold via a reproducible filtration-based method. The integrity and biomechanical performance of the collagen/PLA scaffolds are preserved after cMWCNT integration. In vitro safety assessment of cMWCNT/collagen/PLA scaffolds shows no cytotoxicity effects nor macrophage pro-inflammatory response, supporting further in vitro studies. The cMWCNT/collagen/PLA scaffolds enhance chondrocytes metabolic activity while maintained high cell viability and extracellular matrix (i.e., type II collagen and aggrecan) production. Comprehensive in vitro study applying static and pulsed magnetic field on seeded scaffolds show no specific cell response in dependency with the applied field. This result is independent of the presence or absence of cMWCNT into the collagen/PLA scaffolds. Taken altogether our findings provide additional evidence of the benefits to exploit the CNTs outstanding properties in the design of stimuli-responsive scaffolds. This article is protected by copyright. All rights reserved.