Sunlight Triggers the Activation of Sodium Percarbonate for Toxic-Byproduct-Free Disinfection of Antibiotic-Resistant Bacteria

The abuse of antibiotics leads to widespread antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) in water systems, threatening public health. Existing disinfection technologies have limitations including the generation of toxic disinfection byproducts (DBPs) and inefficiency in eliminating intracellular ARGs. Herein, we provide an effective and toxic-DBP-free disinfection approach to remove ARB/ARGs by reactive species generated via activation of sodium percarbonate (SPC) inside and outside cells with naturally abundant sunlight. Combining in situ characterization and theoretical calculation, we reveal that CO₃^•-, ^•OH, and O₂^•- are generated both intra- and extracellularly. SPC passively diffusing into cells complexes with intracellular substances (e.g., heme, Fe-S cluster protein, and cytochrome c) to produce various reactive species in situ under sunlight irradiation, leading to the locally increased oxidation levels within cells. These reactive species synergistically contribute to the collapse of the antioxidant system, resulting in effective ARB inactivation and ARGs degradation. Owing to its limited reactivity toward background substances in water and effective intracellular oxidation mechanisms, the SPC/sunlight system demonstrates efficient ARB disinfection capabilities without any toxic DBPs generation in real water. This study presents a green, cost-effective, and toxic-DBP-free alternative for efficient ARB/ARGs removal with deep insights into intracellular oxidation mechanisms.