Design of a biofluid-absorbing bioactive sandwich-structured Zn-Si bioceramic composite wound dressing for hair follicle regeneration and skin burn wound healing.

The deep burn skin injures usually severely damage the dermis with the loss of hair follicle loss, which are difficult to regenerate. Furthermore, severe burns often accompanied with large amount of wound exudates making the wound moist, easily infected, and difficult to heal. Therefore, it is of great clinical significance to develop wound dressings to remove wound exudates and promote hair follicle regeneration. In this study, a sandwich-structured wound dressing (SWD) with Janus membrane property was fabricated by hot compression molding using hydrophilic zinc silicate bioceramics (Hardystonite, ZnCS) and hydrophobic polylactic acid (PLA). This unique organic/inorganic Janus membrane structure revealed excellent exudate absorption property and effectively created a dry wound environment. Meanwhile, the incorporation of ZnCS bioceramic particles endowed the dressing with the bioactivity to promote hair follicle regeneration and wound healing through the release of Zn and SiO ions, and this bioactivity of the wound dressing is mainly attributed to the synergistic effect of Zn and SiO to promote the recruitment, viability, and differentiation of hair follicle cells. Our study demonstrates that the utilization of the Janus membrane and synergistic effect of different type bioactive ions are effective approaches for the design of wound dressings for burn wound healing.