Effect of inertial acoustic cavitation on antibiotic efficacy in biofilms

Bacterial biofilms can lead to chronic infections,increase tolerance to antibiotics and disinfectants,resistance to phagocytosis,and other components of the body’s immune system.Biofilm formation is implicated in the persistence of staphylococcal infections and chronic Pseudomonas aeruginosa lung infections in cystic fibrosis(CF)patients(which can result from biofilm-growing mucoid strains).Conventional treatments utilize aggressive antibiotic prophylaxis/therapy to prevent/eliminate biofilms,followed by chronic suppressive therapy.Recently,the use of enzymes to dissolve the biofilm matrix was investigated,in addition to quorum sensing inhibitors to increase biofilm susceptibility to antibiotics.Here,we propose a novel strategy,utilizing ultrasound-induced inertial cavitation,to increase antibiotic efficacy.The wall shear stress at the biofilm interface is calculated,and viscoplastic constitutive equations are used to examine the biofilm response to the mechanical stress.Our simulations suggest that the maximum biofilm detachment occurs at high pressure/low frequency,and the mechanical disruption can affect the biochemical processes inside the biofilm resulting in vulnerability to antibiotics.