Plasma-Activated Water Shows Promise as Alternative Antimicrobial Agent

Research from Xi'an Jiaotong University presents a new approach to optimizing the adaptability of plasma-activated water (PAW) as an antimicrobial agent for pH-sensitive medical scenarios. The study highlights the potential of PAW in disinfection and infection control, despite its limitations in acidic conditions. By pre-loading hydrogen peroxide (H2O2) before plasma activation, researchers achieved a 5-log improvement in the inactivation of Staphylococcus aureus at pH 4.0, with a 99.999% inactivation rate.

Key Takeaways:

• Plasma-activated water (PAW) shows promise as an alternative antimicrobial agent for disinfection and infection control due to its broad-spectrum bactericidal activity and high biosafety.
• Pre-loading 0.1% H2O2 prior to plasma activation elevates the bactericidal pH threshold of PAW to milder acidic conditions, achieving 99.999% inactivation of S. aureus at pH 4.0.
• The study proposes a strategy to optimize the adaptability of PAW as an antimicrobial agent for pH-sensitive medical scenarios, offering insights into the roles of acid environments and H2O2 in bacterial inactivation.
• The research was funded by the National Natural Science Foundation of China (NSFC), Shaanxi Postdoctoral Research Project, Fundamental Research Funds for the Central Universities, and Opening Research Fund from Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research.
• The study suggests that PAW pre-loaded with H2O2 contains much higher concentrations of reactive species, which damage bacterial membranes at low pH (2.0-3.0), significantly inactivating bacteria.

Statistics:

• 5-log improvement in the inactivation of Staphylococcus aureus at pH 4.0.
• 99.999% inactivation rate of S. aureus at pH 4.0.
• 0.1% H2O2 concentration used in the pre-loading process.

Sources:

• Pre-loaded H2O2 Breaks the Low-ph Dependency of Plasma-activated Water for Bacteria Inactivation Via Catalase Suppression and Oxidative Attack. Applied Physics Letters, 2025;127(5).
• Zifeng Wang et al. "Pre-loaded H2O2 Breaks the Low-ph Dependency of Plasma-activated Water for Bacteria Inactivation Via Catalase Suppression and Oxidative Attack." Applied Physics Letters 127, no. 5 (2025).
• Xi'an Jiaotong University. State Key Lab Elect Insulat & Power Equipment, Xian 710049, People's Republic of China.