title: Removal of biofilms by intermittent low-intensity ultrasonication triggered bursting of microbubbles.
abstract: In this study, a chemical-free cleaning method for biofilms removal is presented, which is based on intermittent low-intensity ultrasonication (US) triggered bursting of microbubbles (MB) in such a sequence that MB were continuously introduced into the reaction vessel for 15 min, while US was activated for 2 s after every 2 min of microbubbling. It was found that the fixed biomass, and the extracellular proteins and polysaccharides of 24-h old biofilms grown on a nylon membrane surface were reduced, respectively, by 75, 79 and 72% after treatment by the US + MB method. Fourier transform infrared (FTIR) analysis further revealed that the chemical composition of the biofilms was not altered by the US + MB treatment, suggesting that biofilms were removed through physical forces due to the generation of a shock wave and a high-speed water jet through US-triggered bursting of the MB. The proposed method can be considered a chemical-free technology for biofilm removal.
authors.affiliation: a Division of Environmental and Water Resources Engineering, School of Civil and Environmental Engineering , Nanyang Technological University , 50 Nanyang Avenue, Singapore 639798 , Singapore.
authors.forename: Ashutosh
authors.initials: A
authors.lastname: Agarwal
authors.forename: Wun
authors.initials: W
authors.lastname: Jern Ng
authors.forename: Yu
authors.initials: Y
authors.lastname: Liu
mesh_terms: D001422:Bacterial Adhesion; D018441:Biofilms; D057219:Biofouling / Q000517:prevention & control*; D008567:Membranes, Artificial; D045423:Microbubbles; D013010:Sonication; D062065:Wastewater / Q000382:microbiology
chemical_list: D008567:Membranes, Artificial; D062065:Wastewater