Trypan blue solution 0.4

Mesenchymal stem cell growth medium 2 (Ready-to-use; PromoCell, Heidelberg, Germany), mesenchymal stem cell neurogenic differentiation medium (Ready-to-use; PromoCell), human fibronectin solution (1 mg/mL; PromoCell), and all cell culture reagents were purchased from Carlo Erba Reagents (Carlo Erba Reagents S.r.l., Cornaredo, Italy), 75 cm² tissue culture flask with vented filter caps and 96- and 6-well plates (Corning), Trypan blue solution (0.4%), cresyl violet acetate, and MTT ((3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) were purchased from VWR International PBI (Milan, Italy). CellTiter-Glo^® 3D Cell Viability and Caspase-Glo^® 3/7 assays were acquired from Promega (Milan, Italy). Primary antibodies (Santa Cruz Biotechnology, Dallas, TX, USA) conjugated to alexa-fluo^®488 or 594 (Santa Cruz Biotechnology) for nestin, SOX-2, enolase (NSE), MAP-2, β-Tubulin III, synaptophysin (SYN), growth-associated protein 43 (GAP43), post-synaptic density 95 (PSD95), and primary antibody for glial fibrillary acidic protein (GFAP; Santa Cruz Biotechnology) were purchased from D.B.A. Italia s.r.l (Segrate (MI), Italy). Hoechst 33258 (Invitrogen, Waltham, MA, USA) was provided by Life Technologies Italia (Monza, Italy). Polyvinylpyrrolidone coated Fe₃O₄NPs were obtained from nanoComposix (San Diego, CA, USA; lot no. ECP1475).

HFF-1 Human foreskin fibroblasts were sourced from ATCC (Manassas, Virginia, VA, USA) trypan Blue Solution 0.4% (w/v) in PBS was sourced from Corning (Corning, New York, NY, USA), trypsin-EDTA (0.25%) phenol red, Dulbecco’s Modified Eagle Medium (DMEM), penicillin-Streptomycin (10,000 U/mL), Fetal Bovine Serum (FBS), L-Glutamine (200 mM), thiazolyl blue tetrazolium bromide, silver nitrate, calcium chloride pellets and sodium alginate powder were all sourced from Sigma-Aldrich (St. Louis, MO, USA). PBS Tablets were sourced from Fisher BioReagents, aloe vera gel was sourced from Holland and Barrett and Lysogeny broth (LB) (miller) was sourced from Merck (Darmstadt, Germany).