Plant Ash/Polylactic Acid Electrospun Fiber Dressing Promotes Wound Healing Through pH Regulation

Abstract

Wound healing has always been a focal point in medicine and fabrication of biomaterials. Nanofibers made from polylactic acid (PLA) promote wound healing and possess antibacterial properties. However, the acidic byproducts of PLA can hinder the wound-healing process. Plant ash, being mildly alkaline, has the potential to neutralize these acidic compounds. A nanofiber film combining PLA and plant ash can create a neutral environment conducive to cell growth. Additionally, the growth-promoting components of plant ash can further accelerate wound healing. In this study, we combined PLA with plant ash and electrospun the mixture into nanofibers, ultimately developing a pH-regulating wound dressing. We prepared a mixed emulsion containing grass and wood ash, PLA powder, and a polymer surfactant to fabricate the dressing. The emulsion was then frozen to reduce the solubility of the solvent, facilitating the precipitation of the plant ash/PLA mixture. Subsequently, nanofibers were produced from the precipitated powder through electrospinning, which were employed to create the wound dressing. We evaluated the degradation of the dressing in normal saline and monitored the pH changes over two weeks. The pH remained stable at 7–8, indicating a neutral to mildly alkaline state. This result confirms an optimal environment for wound healing.