Ferroelectric catalytic BaTiO3-based composite insoles to promote healing of infected wounds: Analysis of antibacterial efficacy and angiogenesis

Our feet are often subjected to moist and warm environments, which can promote the growth of harmful bacteria and the development of severe infection in wounds located in the foot. As a result, there is a need for new and innovative strategies to safely sterilize feet, when shoes are worn, to prevent any potential foot-related diseases. In this paper, we have produced a non-destructive, biocompatible and convenient-to-use insole by embedding a BaTiO₃ (BT) ferroelectric material into a conventional polydimethylsilane (PDMS) insole material to exploit a ferroelectric catalytic effect to promote the antibacterial and healing of infected wounds via the ferroelectric charges generated during walking. The formation of reactive oxygen species generated through a ferroelectric catalytic effect in the PDMS-BT composite is shown to increase the oxidative stress on bacteria and decrease both the activity of bacteria and the rate of formation of bacterial biofilms. In addition, the ferroelectric field generated by the PDMS-BT insole can enhance the level of transforming growth factor-beta and CD31 by influencing the endogenous electric field of a wound, thereby promoting the proliferation, differentiation of fibroblasts and angiogenesis. This work therefore provides a new route for antimicrobial and tissue reconstruction by integrating a ferroelectric biomaterial into a shoe insole, with significant potential for health-related applications.