Polymer-based multiferroics, combining magnetic and piezoelectric properties, are studied experimentally—from synthesis to multi-parameter characterization—in view of their prospects for fabricating biocompatible scaffolds. The main advantage of these systems is facile generation of mechanical deformations and electric signals in response to external magnetic fields. Herein, we address the composites based on PVDF-TrFE polymer matrices filled with a combination of piezoelectric (BaTiO_3, BTO) and/or ferrimagnetic (Zn_0.25Co_0.75Fe₂O₄, ZCFO) particles. It is shown that the presence of BTO micron-size particles favors stripe-type structuring of the ZCFO filler and enhances the magnetoelectric response of the sample up to 18.6 mV/(cm∙Oe). Besides that, the admixing of BTO particles is crucial because the mechanical properties of the composite filled with only ZCFO is much less efficient in transforming magnetic excitations into the mechanical and electric responses. Attention is focused on the local surfacial mechanical properties since those, to a great extent, determine the fate of stem cells cultivated on these surfaces. The nano-indentation tests are accomplished with the aid of scanning probe microscopy technique. With their proven suitable mechanical properties, a high level of magnetoelectric conversion and also biocompatibility, the composites of the considered type are enticing as the materials for multiferroic-based polymer scaffolds.

Magnetoelectric composites based on polymers with inclusions of magnetic nanoparticles have found novel applications in bone tissue engineering as growth-promoting substrates for stem cells. Current research focuses on the surface properties of composite materials, in particular their topographical features, as these have a significant impact on the behavior of stem cells and can promote their differentiation. In this paper, helium-plasma modification is proposed as a method to effectively modify the surface roughness and wettability of polyvinylidene fluoride (PVDF)-based films. It is demonstrated that this modification method facilitates the development of a topography and increases the surface roughness of PVDF substrates; it also contributes to a reduction in the contact angle, which is due to surface functionalization through defluorination and chemical oxidation. Such surface properties make it possible to use these nanocomposites as functional substrates for bone tissue engineering.