Optimization of Super Oxidized Water Redox Properties by DOE for Targeted Disinfection Applications

Super oxidized water is a disinfectant generated by electrolysis whose effectiveness depends mainly on oxidation–reduction potential and pH. In this study, a 22 factorial Design of Experiments was applied to evaluate the influence of applied potential (8.2–12.2 V) and NaCl concentration (0.05–0.25 wt.%) on the redox properties of SOW, aiming to produce solutions with targeted disinfection profiles. The obtained models showed excellent predictive capacity (R2 > 0.99), identifying NaCl concentration as the most influential factor affecting both oxidation–reduction potential and pH. The system enabled the controlled generation of SOW with ORP values ranging from approximately 950 to 1100 mV and pH between ~3.8 and 5.0, with experimental errors below 1.5%. Stability tests demonstrated that oxidation–reduction potential and pH remained within ±25 mV and ±0.15 units, respectively, over 24 weeks of storage. Microbiological evaluation revealed effective antimicrobial activity against Escherichia coli, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, and Candida albicans, with inhibition halos of up to ~5 mm depending on ORP and microorganism. The results demonstrate that Design of Experiments enables precise adjustment of SOW redox properties, allowing optimization of antimicrobial performance for specific applications. This positions super oxidized water as a flexible, stable, and scalable disinfection technology for industrial and clinical use.