Unilateral Surface-Crystal-Engineering Induced Dual-Bionic Janus Multifunctional Wound Dressing for Infected Burn Wound Healing

Infected burn wounds pose significant challenges to traditional dressings, as excessive exudate secretion and persistent inflammation delay wound healing. To address these challenges, a three-layer Janus multifunctional wound dressing (MFWD) with dual-bionic design is proposed and fabricated via a unilateral surface-crystal-engineering strategy. The lower layer is attired by a biomimetic topological structure via epitaxial crystallization of polyethylene glycol-polycaprolactone (PEG-PCL) diblock copolymer on the PCL electrospun fibers, endowing the hydrophilic feature. The transport layer, composed of intermediate nonwoven fabric, is sandwiched between the hydrophilic lower layer and the hydrophobic upper layer (pristine PCL electrospun fibers). Benefiting from the designed gradient structure, MFWD efficiently manages exudate by directional pumping water in contact with the lower layer outward. The hydrophobic upper layer as a barrier prevents external liquids from infiltrating the dressing. Additionally, the collagen fiber-like topography on the lower fibers promotes cell spreading and migration. Attributed to the above superior performance, MFWD demonstrates excellent exudate management, infection and inflammation reduction, and collagen deposition promotion, significantly accelerating infected burn wound healing. This Janus multifunctional dressing is a promising candidate for the treatment of infected burn wounds.