Magnetic poly(ε-caprolactone)-based nanocomposite membranes for bone cell engineering

[Display omitted] •Iron oxide nanoparticles were stabilized by caprylic, palmitic, and stearic acids.•Incorporation of the particles in nanocomposite poly(ε-caprolactone) membranes increased Young’s modulus and decreased stress and strain at break.•The cytotoxicity toward the SAOS-2 cells increased with the enhanced length of carbon chains of fatty acids.•The membranes are intended for non-invasive stimulation of bone cells using remote magnetic field. Magnetic polymer nanocomposites manipulatable by an external magnetic field have a great potential for bone tissue regeneration. Various strategies have been proposed for their fabrication, as uniform distribution of magnetic nanoparticles (MNPs) within the polymer matrix remains to be the main challenge. The aim of this study was to design poly(ε-caprolactone) (PCL) matrix containing iron oxide nanoparticles stabilized by saturated fatty acids with the increasing number of carbon atoms, i.e., caprylic (CA), palmitic (PA), and stearic acids (SA). We investigated the effect of the type of fatty acid and the content of particles in nanocomposite membranes on their physicochemical properties and biological response toward the SAOS-2 cells. The incorporation of the MNPs in PCL matrix resulted in a gradual increase of Young’s modulus, a slight decrease of tensile strength, and a significant decrease of stress and strain at break. The addition of SA-stabilized MNPs (1 wt%) in the PCL matrix increased its strength. The membranes containing CA-stabilized MNPs remained non-toxic towards SAOS-2 cells, while the cytotoxicity of other nanocomposites increased with the enhanced length of carbon chains of fatty acids stabilizing MNPs, as well as with their increasing content in membranes.