A synergistic Janus nanofiber dressing enables spatiotemporal sequential treatment of acute wounds

Acute wound healing is often impeded by uncontrolled infection and persistent inflammation. This highlights the need for multifunctional dressings capable of spatiotemporally coordinated intervention. Here, we report a synergy-driven 'defense-regulation' Janus dressing (DRJD) integrating traditional Chinese medicine (TCM) and western therapeutics. The hydrophobic outer layer (DRJD-O) is composed of polyacrylonitrile (PAN) and thermoplastic polyurethane (TPU) nanofibers loaded with fusidic acid (FA), forming a physical barrier that rapidly intercepts invading bacteria and provides sustained antibacterial protection. In contrast, the hydrophilic inner layer (DRJD-I) is based on polyvinyl alcohol (PVA) and incorporates Atractylodes macrocephala extract (AME), which rapidly dissolves as a sacrificial layer upon exposure to wound exudate, triggering an early burst release of anti-inflammatory components to modulate the microenvironment in the early inflammatory phase. Janus architecture encodes a spatiotemporally ordered release profile, whereby early microenvironment regulation by AME is followed by prolonged FA-mediated antibacterial defense to prevent reinfection. In vitro assays demonstrated potent synergistic antibacterial activity against S. aureus and E. coli, alongside a significant suppression of M1 macrophage polarization, indicating immunomodulatory efficacy. In the full-thickness rat wound model, DRJD significantly accelerated wound healing. It also promoted strong re-epithelialization, enhanced collagen maturity, and stimulated angiogenesis. Histological and immunohistochemical analyses further revealed that the expression of TNF-α was reduced and the density of CD31-positive microvessels was increased. These changes indicate that the wound milieu shifted from an inflammatory to a regenerative state. This study establishes a spatiotemporally coordinated external defense-internal regulation model, providing a promising translational platform for the treatment of acute and potentially chronic wounds.