Highly Flexible and Conformable ZnO/FeGa Magnetoelectric Heterostructures for Skin wound Healing.

Composite magnetoelectric (piezoelectric/magnetostrictive) materials are gaining an increased interest due to their appealing wireless actuation capabilities. For many applications, such as sensing, energy harvesting or cell electrostimulation, flexible and adaptable heterostructures are required. However, some of the proposed structures suffer from poor magnetoelectric performance due to their inherent stiffness and the resulting substrate clamping effects. Here, a highly flexible and conformable nanostructured ZnO(piezoelectric)/FeGa(magnetostrictive) magnetoelectric heterostructure embedded in a low Young's modulus elastomer (polydimethylsiloxane; PDMS) is presented. This heterostructure is designed to enhance wound healing via electric stimulation induced by low-intensity and low-frequency AC magnetic fields. In vitro testing using normal human dermal fibroblasts (NHDF) and human keratinocytes (HaCaT) cell cultures demonstrated high cell viability and no adverse effects under magnetoelectric stimulation. Moreover, the magnetoelectric stimulation significantly enhanced keratinocyte stratification and fibroblast collagen production, with remarkable improvements in cell migration compared to non-stimulated cells. These results underscore the potential of highly flexible magnetoelectric heterostructures as active dressings to improve wound healing processes, especially relevant for chronic wounds and other epithelial disorders.