Design And Application Of Wound Healing Acceleration Device Based On Mechanical And Electrical Synergetic Stimulation

Wound healing has become a significant burden to public health care system,and appropriate dressing intervention will help to accelerate the process of wound healing.Among the interventions,wound tension regulation and electrical stimulation have shown great potential in promoting wound healing.However,the lack of portbility of related devices and the complexity of stimulation scenarios are still challenges in clinical application.Based on the shape memory effect of shape memory alloy and the electric field distribution on the surface of electrostatic electret,a wound dressing with mechanical and electrical co-stimulation is proposed in this thesis.Through the patterning process,driven by body temperature,the dressing can apply appropriate local stress and electrical stimulation to the wound.From in vivo studies,the animal experiment result shows that,under 10% contraction strain,linear and circular wounds could be closed effectively in 4days and 8 days,respectively,with about 50% improvement in wound closure rate versus the nonintervention controls statistically.Through the analysis of wound section,it was found that the dressing could effectively promote the secretion of growth factors,such as VEGF,TGF-?,and accelerate the process of wound re-epithelialization.In addition,to overcome the electical field attenuation characteristic of electrostatic electrets,a wearable electrical stimulation system based on self-powered stretchable thermoelectric generator is developed.The electrical stimulation system based on STEG can fully utilize human body heat as the energy source and make conformal contact to the human skin,creating an ideal solution.In order to reduce the thermal conduction resistance,direct contact between electrode and human body was adopted,and a preparation method using photoresist and spin coating process was proposed for large area preparation.The performance test results indicated that STEG showed reliable under30% tensile strain,and achieved an output of 25 m V at ?T = 10 K.By using self-supplied boost module,the system achieved electrical stimulation of 2.35 V.The research on electromechanical synergistic dressing and its alternative power supply provide an effective self-powered treatment for dressing to improve the wound environment,inhibit wound infection and accelerate the healing of wound.