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[Display omitted] • Nanowire-assisted electroporation (<3.0 V) was the main disinfection mechanism. • DV caused poor cell inactivation on cathode and cell adsorption-fouling on anode. • SWAV enabled effective cell inactivation and fouling resistance on both electrodes. • SWAV showed stable and efficient G- and G + inactivation in DI, tap and lake waters. • SWAV regulated cell migration, adsorption, inactivation, and desorption on nanowire. Nanowire-assisted electroporation is regarded as an effective point-of-use disinfection technique for drinking water, and its performance under direct voltage (DV, U) supply is limited by the poor bacterial inactivation on cathode and bacterial adsorption-fouling on anode. Herein, square-wave alternating voltage (SWAV, ± U) was applied on nanowire electrodes to periodically reverse the cathodic/anodic polarity and their repulsions/attractions with bacterial cells, in turn promoting cell inactivation and fouling resistance. As compared with the gradual decrease in cell inactivation by the biofouling on nanowire anode under DV supply, SWAV supply enabled stable and efficient disinfection with ∼ 2 log higher cell inactivation and ∼ 3 times lower energy consumption (0.32–11.3 Wh/m3/log at 1.0–3.0 V) for various G- (Escherichia coli and Acinetobacter schindleri) and G+ (Enterococcus faecalis and Bacillus cereus) bacteria in deionized water, tap water and lake water. The cell morphology observation, flow cytometry analyses, and quenching experiments of reactive species revealed that electroporation on nanowire interfaces with locally enhanced electric field was the main mechanism for bacterial inactivation under voltages below 3.0 V. It was revealed that reversion of electrophoretic and electrostatic attractions under SWAV supply regulated cell migration, adsorption and desorption on nanowire interface, resulting in cell inactivation and fouling resistance on both nanowire electrodes. This work opens an effective strategy for stable and efficient nanowire-assisted electroporation disinfection. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synergistic electroporation/chlorination was constructed to promote i-ARG removal. • DC-EP/Cl 2 promoted the damage of ARB cells for i-ARG leakage and removal. • DC-EP/Cl 2 decreased significantly the HGT frequency than individual treatment. • DC-EP/Cl 2 had much lower energy consumption for i-ARG removal in tap water. • DC-EP/Cl 2 exhibited excellent stability of i-ARG removal within 7-day operation. Conventional chlorination (Cl 2) is inefficient to eliminate intracellular antibiotic resistance genes (i-ARGs) of antibiotic-resistant bacteria (ARB) due to the chlorine permeation barrier and oxidative competition of cell wall/membrane. Herein, we proposed an efficient strategy by constructing synergistic nanowire-induced electroporation (DC-EP) and Cl 2 (DC-EP/Cl 2) with H 2 -reduced TiO 2 nanowire (TiO x NW) electrodes, attempting to promote i-ARG removal via DC-EP-induced cell damage for chlorine permeation and i-ARG leakage. DC-EP/Cl 2 (∼3.7 log and ∼ 60.5 J/L/log) exhibited excellent synergistic effects for ARB inactivation (Escherichia coli) and i-ARG removal (tet(W) , aac(3)-II , and bla TEM – 1), which achieved much larger i-ARG removal and lower energy consumption than the individual 1.5 V-DC-EP (∼0.05 log) and 10 mg/L-Cl 2 (∼0.5 log and ∼ 262.0 J/L/log). Analyses of i-ARG/e-ARG abundances, bacterial cell integrity, and cell morphology indicated that DC-EP-induced cell pores provided channels of chlorine permeation, which was accompanied with oxidative enlargement of cell pores for i-ARG leakage and subsequent degradation. DC-EP/Cl 2 exhibited 15–90 times lower frequency of horizontal gene transfer than the individual Cl 2 disinfection. The TiO x NW-based DC-EP/Cl 2 exhibited excellent stability of i-ARG removal (undetectable ARG abundance and ∼ 20.3 J/L/log) for treating 103 CFU/mL ARB-contaminated tap water within 7-day continuous operation, suggesting its great application potential to alleviate ARG dissemination risk for drinking water. [ABSTRACT FROM AUTHOR]