Flexible Electromagnetic Coil Patch-enhanced Healing of Full-Thickness Skin Wounds in Rats

Chronic and large skin wounds present significant clinical challenges due to delayed healing and high infection risk. Pulsed electromagnetic field (PEMF) therapy is a non-invasive approach that can promote tissue repair. This study describes a reproducible rat wound model protocol using a flexible printed copper coil patch connected to a custom PCB controller to deliver localized PEMF stimulation to full-thickness dorsal wounds. The contralateral wound served as an untreated control. Healing progression was assessed through regular photography and wound area measurements. The protocol provides a practical, adaptable system for evaluating and optimizing PEMF-based therapies in vivo across various conditions, with a focus on localized application and parameter adjustment for regenerative medicine. Parameter selection was based on an orthogonal CCK-8 screen of fibroblast proliferation that tested 0.25-1.3 mT, 10-40 Hz, and 30-90 min/day; main-effect analysis identified 1.3 mT, 30 Hz, and 60 min/day as the optimal levels, which were adopted for in vivo testing.