Bioactive chitosan-based scaffolds with improved properties induced by dextran-grafted nano-maghemite and l-arginine amino acid.

Over the past years, fundamentals of magnetism opened a wide research area of interest, in the field of tissue engineering and regenerative medicine. The integration of magnetic nanoarchitectures into synthetic/natural scaffold formulations allowed obtaining "on demand" responsive structures able to guide the regeneration process. The aim of this work was the design and characterization of three-dimensional (3D) chitosan-based scaffolds containing dextran-grafted maghemite nanoarchitectures (DM) and functionalized with l-arginine (l-Arg) amino acid as bioactive agent. A homogeneous pore distribution and a high degree of interconnection were obtained for all the structures with DMs, which resulted well distributed inside the polymer matrix. All the results suggest that the simultaneous presence of DMs and l-Arg conferred interesting mechano-structural and bioactive properties toward osteoblast-like and human mesenchymal stem cells, differentially stimulating their proliferation both in the absence and in the presence of a time-dependent magnetic field. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 1244-1252, 2019.