Fig. 5

Colony-forming unit (CFU/mL) counts are shown for four treatment conditions: synchronous exposure to electric field and vancomycin (SYNC), and asynchronous protocols with a delay of 6 min (ASYNC-DT₆), 12 min (ASYNC-DT₁₂), and 60 min (ASYNC-DT₆₀) in vancomycin exposure after electric field stimulation. Bars represent mean ± standard deviation (n = 3) of colony-forming unit counts (CFU/mL), shown on a logarithmic scale. One-way ANOVA revealed a highly significant difference across the groups (p < 0.001). Post-hoc comparisons confirmed that SYNC resulted in significantly lower CFU/mL than both ASYNC-DT₁₂ (p < 0.001) and ASYNC-DT₆₀ (p < 0.001), whereas no significant difference was observed between SYNC and ASYNC-DT₆ (p = 0.999). These results support the existence of a transient EFIVW, maintained for up to 6 min post-stimulation, during which biofilm cells exhibit enhanced susceptibility to antibiotic treatment.