Preparation and design of intelligent multi-response PTMC/PVP composite nanofibrous dressing to promote wound closure and its applications in diabetic wounds

The healing process of diabetic wounds is characterized by a slow and arduous progression, making it challenging to achieve wound closure and complete healing through self-contraction, as observed in normal wounds. In this study, an intelligent multi-responsive composite of polytrimethylene carbonate (PTMC)/polyvinylpyrrolidone (PVP) nanofibrous dressing (C-PPZS) loaded with simvastatin-loaded ZIF-8 nanoparticles (ZIF-8@SIM NPs) was fabricated via electrospinning technology. The dressing exhibited liquid-triggered and temperature-controlled shrinkage characteristics, as well as pH-responsive drug release properties. When subjected to a temperature of 37 ℃ for 60 min, the area shrinkage rate of PPZS in PBS was determined to be 78.36 ± 1.14 %, and C-PPZS also reduced the area of isolated mouse skin defects to 38.01 ± 2.33 % of its original size. Furthermore, in vitro studies demonstrated that C-PPZS exhibited favorable biocompatibility and proangiogenic properties, along with significant inhibitory effects against S. aureus and E. coli . In vivo experiments conducted on diabetic mice revealed that C-PPZS facilitated wound closure and healing, attenuated scar formation, stimulated collagen fiber deposition, and promoted vascular regeneration. In conclusion, C-PPZS has great potential as an advanced dressing for the treatment of chronic wounds.