Enhancing the Inactivation of Biofilm‐Forming Pathogenic Bacteria With Sodium Pentaborate Pentahydrate by Ultrasound

ABSTRACT Biofilm‐forming bacteria in water system represent a persistent challenge due to their increased tolerence to conventional antimicrobial treatments. In this study, the antimicrobial effects of combined application of ultrasound and a boron derivative Sodium Pentaborate Pentahydrate (NaB), against biofilm‐forming pathogenic bacteria were investigated as a boron‐based ultrasound‐assisted antibiofilm strategy. NaB exhibited antibacterial activity with minimum inhibitory concentration (MIC) values of 16 mg/mL for Escherichia coli and Klebsiella pneumoniae and 8 mg/mL for Staphylococcus aureus. In biofilm attachment assays, the combined NaB‐US treatment reduced viable biofilm‐associated bacterial counts from 4.92 to 4.71 log CFU/mL for E. coli, from 5.18 to 4.46 log CFU/mL for K. pneumoniae, and from 5.73 to 5.45 log CFU/mL for S.aureus compared with NaB treatment alone. Similarly, biofilm inhibition increased from 22.20% to 30.36% for E.coli, from 56.30% to 68.29% for K. pneumoniae, and from 74.00% to 82.44% for S. aureus following ultrasound‐assisted treatment. These findings demonstrate that ultrasoundsignifically enhances the antibiofilm efficacy of NaB, likely through cavitation‐mediated disruption of bacterial aggregates and improved antimicrobial penetration. The synergistic combination of NaB and ultrasound represents a promising and environmentally friendly strategy for controlling biofilm forming pathogens in water systems and disinfection applications.