Construction of conductive polyimide dressings for accelerated wound healing via an interfacial compatibility optimization and polyelectrolyte complexation synergistic strategy

Polyimide (PI) has excellent biocompatibility and structural stability. However, its intrinsic hydrophobicity and electrical insulating nature severely limit its application in functional wound dressings. Although the integration of conductive polymers can impart electrical conductivity to PIs, interfacial instability between the PI matrix and conductive networks remains a critical challenge. Here, we propose a synergistic strategy, namely “interfacial compatibility optimization and polyelectrolyte complexation”, to fabricate a highly hydrophilic and conductive PI/MXene/polyaniline (PANI) composite sponge dressing. Intrinsic hydrophilicity was achieved by incorporating a sulfonic acid-containing diamine monomer (BDSA) into the PI backbone, resulting in water droplets being completely absorbed within 1.99 ± 0.14 s instead of over 120 s without full dressing absorption, with water absorption capacity and exudate absorption capacity increasing by 315.97% and 79.55%, respectively. Moreover, the negatively charged MXene nanosheets not only facilitate the electrostatic adsorption of protonated aniline monomers at the PI interface for uniform in situ PANI polymerization, but also further form an efficient hybrid conductive network with PANI, with a maximum electrical conductivity of 7.90 × 10⁻² S/cm. In vitro experiments demonstrated excellent biocompatibility and significantly enhanced the proliferation of L929 cells under an electric potential difference of 400 mV. Furthermore, a full-thickness skin defect model in Sprague–Dawley rats revealed that the electroactive PI/MXene/PANI dressing markedly accelerated wound healing, resulting in nearly complete closure with hair follicle regeneration within 14 days. This work establishes a molecular-level design paradigm for overcoming interfacial instability in conductive PIs systems and advances the development of high-performance electroactive wound dressings.