Physicochemical properties of plasma-activated water and its therapeutic potential for wound management in rats

Plasma-activated water (PAW) is an emerging biocompatible antiseptic with potential applications in regenerative medicine. In this study, we characterized the physicochemical properties of PAW and evaluated its wound-healing efficacy relative to that of hydrogen peroxide (H₂O₂) in a rat full-thickness skin defect model. PAW was generated by exposing phosphate-buffered saline (PBS) to a surface-discharge plasma for 2–10 min. With increasing activation time, pH decreased gradually from 7.4 to 4.8, while reactive oxygen and nitrogen species accumulated (H₂O₂ up to 95 μmol/L; total nitric oxide (NO) up to 198 μmol/L). In vivo, PAW accelerated closure, enhanced collagen deposition, and improved epithelial and follicular regeneration compared with H₂O₂ or untreated controls. Immunofluorescence revealed a higher expression of protein gene product 9.5, indicating attenuated inflammation and enhanced reinnervation. The balanced redox composition of PAW resulted in antimicrobial activity with minimal cytotoxicity, as evidenced by its stable body weight and preserved tissue architecture. Collectively, these findings indicate that PAW is a safe, effective, and readily produced therapeutic agent that simultaneously disinfects and promotes tissue repair, thereby offering a promising alternative to conventional oxidizing antiseptics.