Smart bandage with multi-sensor system for wound healing and microenvironment monitoring

Wound healing is a dynamic process involving the upregulation and downregulation of various physico-chemical molecules within the microenvironment. Therefore, timely feedback on relevant healing indicators is essential for improving diagnosis and subsequent therapy. However, current wound bandages are primarily monofunctional, serving only the purpose of wound coverage. To address this limitation, a smart hydrogel bandage capable of monitoring pH, glucose levels, mechanical deformation, and providing anti-infection properties was designed (Scheme 1). First, zig-zag tough elastic hydrogel fibers and a bandage substrate were fabricated using the procrystallization effect of polyvinyl alcohol (PVA). These hydrogel fibers were then loaded with phenol red, glucose oxidase (GOx), horseradish peroxidase (HRP) enzyme, and carbon nanotubes, respectively. After installing the hydrogel fibers into the grooves of the PVA substrate and applying a glycerol coating to prevent drying, the device was covered with an ultra-thin adhesive layer to complete the smart bandage. An applet was developed to deliver wound information in a timely manner by reading the color transitions of the flexible device and converting them into RGB values. The photo-thermal antimicrobial effects of carbon nanotubes (CNTs) were demonstrated in vivo by inhibiting infection and reducing inflammatory infiltrates, and their resistance synchronized with mechanical movement indicates their potential to measure wound tension. Therefore, the smart bandage demonstrates significant potential to enhance wound healing.