Self-Driven Drug Release Dual-Layer Dressing Composed of Electrospun Membrane and Hydrogel with Dynamic Structure Based on Piezoelectricity Transformation and Electrical Responsiveness.

This study reports the development of an intelligent dual-layer wound dressing engineered to achieve active wound repair. The self-standing dressing integrates a polyvinylidene fluoride (PVDF) piezoelectric electrospun membrane with a multifunctional hydrogel based on interfacial fusion. The PVDF layer converted mechanical energy derived from human body movement into electrical stimulation, which dramatically motivated the controlled release of diclofenac sodium (DFs) encapsulated in the hydrogel. The relatively small diameter fibers and network caused strong connection with the hydrogel and smooth transfer of electricity. When a positive potential of 1.5 V was applied, up to a 55 μg mL-1 cumulative amount of DFs was released, about five times higher than that only based on drug diffusion. This enhanced release rate resulted from the cooperation of accelerated drug migration under electrically driven and dynamic changes of the gel's microstructure, which was the result of reversible behavior of borate bonds within the hydrogel. Consequently, the hydrogel exhibited self-healing properties and a tensile strain of up to 600%, much higher than that of conventional hydrogels. Under mechanical motivation, the dressing exhibited enhanced DFs release ability, confirming the piezoelectric transition and controlled drug release abilities. Therefore, the present work offers an innovative solution for the intelligent management of chronic wounds.