Smart chitosan-based nanofibers for real-time monitoring and promotion of wound healing

Timely healing of acute wounds and stopping wound chronicity are current and future priorities in wound therapy. It is urgent and relevant to develop a wound dressing that has antimicrobial and monitors the wound microenvironment in real time. In this study, quaternary ammonium chitosan (HTCC) was selected as the antimicrobial agent and CS/PEO/HTCC nanofiber membranes (CPHs) were prepared by electrostatic spinning technique. The nanofiber membrane (CPH91) with the best antimicrobial performance was screened by the disk diffusion method and drug susceptibility testing by dilution method, and its antimicrobial effect on S. aureus was better than that of E. coli. Subsequently, functional carbon dots (CDs) were synthesized by solvothermal method and doped into CPH91 nanofibers by electrospinning. A good linear relationship between pH value (5.0-8.0) and the fluorescence intensity of CDs was observed. In addition, the nanofibers (CPH91@CDs) had good morphology, hydrophilicity, and biocompatibility. Changes in fluorescence intensity of CPH91@CDs at different pH (5.0-8.0) were monitored and converted into RGB values that were linearly fitted to pH value. Finally, the potential of CPH91@CDs of improving wound healing and instantaneously controlling wound healing process was confirmed by an infected wound model (S. aureus) on the back of SD rats.