Tendon injuries represent a global health issue that annually affects millions of individuals. An innovative approach for their treatment is represented by the development of polymeric scaffolds able to support the cells adhesion, differentiation, and proliferation. To improve healing control, we investigated the possible mechano-stimulation of cells when combined with bio-mimetic scaffolds doped with Magnetite nanoparticles (Fe3O4), improving the tenogenic differentiation. We developed and characterized fibrous scaffolds, able to mimic the tendon fascicles, based on polyhydroxybutyrate and gelatin and doped with Fe3O4 nanoparticles. They possess a superparamagnetic behavior and a slow degradation rate that should guarantee structural support during the tissue regeneration. The structural properties of fibrous scaffolds on different length scales were investigated by microscopy, small angle X-ray scattering, infrared spectroscopy, thermal analysis. The macroscopic mechanical properties were correlated with the nanoscopic mechanics of the polymer matrix. Also, the viscoelastic behaviour was investigated by observing the evolution of the nanoscale structure while the scaffolds were subjected to elongation. The magnetic scaffolds promoted cell proliferation and alignment onto the matrix, when combined with the application of an external magnetic field and the cells could differentiate and produce collagen I extracellular matrix. These promising results contribute to the investigation of the mechanisms of external mechanostimulation by static, and in the future oscillating, magnetic fields and to the design of tools to enhance and stimulate the tendon tissue regeneration.

Acknowledgments

Work partially supported by PRIN 2022 - MASTER project (Magnetic responsive smart device for tendon regeneration).