Vanillin and IGF1-loaded dual-layer multifunctional wound dressing with micro-nanofibrous structure for full-thickness wound healing acceleration

Multifunctional dual-layer wound dressings hold significant promise for comprehensive full-thickness wound management by closely mimicking the native skin structure and features. Herein, we employed an innovative approach utilizing electrospinning techniques to develop a dual-layer dressing comprising a microfibrous Ecoflex (R)-Vanillin (Ex-Vnil) top layer (TL) and a nanofibrous Soluplus (R)-Insulin-like growth factor-1 (Sol-IGF1) bottom layer (BL). The tensile properties of dual-layer wound dressings were within the standard range for use in skin tissue regeneration. The TL exhibited hydrophobic properties with a contact angle value of 92.4 degrees and significant antibacterial activity, mimicking the epidermis of the skin, thereby preventing fluid and bacterial penetration. Moreover, the dual-layer wound dressing demonstrated standard water vapour transmission rate, with 91.2 % release of IGF1 and 66.8 % release of Vnil within 5 days. Notably, the fabricated dual-layer dressing promoted cell behaviour and exhibited a significant angiogenesis effect and accelerated healing of full-thickness wound, achieving 96.4 % closure after 14 days, attributed to reduced inflammation, early blood vessel formation, and enhanced collagen density. Our findings underscore the potential of the fabricated dual-layer dressing as an innovative solution in full-thickness wound care.