Noninvasive Control of Bacterial Biofilms by Wireless Electrostimulation

Bacteria are well-known to form biofilms on biomaterials and implanted medical devices and cause serious infections that are incurable by conventional antibiotics. Consequently, such infections can lead to explantation and, in severe cases, amputation or even death. To address this unmet challenge, we developed a new method for noninvasive treatment of device-associated biofilm infections. We demonstrate that antibiotic tolerant biofilm cells of Pseudomonas aeruginosa and Staphylococcus aureus can be effectively killed by electromagnetically induced direct current generated wirelessly using a remote power source, which was further enhanced through synergy with conventional antibiotics. Electrochemical analyses attributed the cidal effects to DC-generated reactive oxygen species. The treatment conditions were found safe to the epithelial and fibroblast cell lines. On the basis of these findings, a prototype device was engineered and demonstrated for effective killing of biofilm cells using both ex vivo and in vivo models. With the capability to kill bacteria without using a directly connected power source, this platform technology has possible applications in noninvasive treatment of biofilm infections associated with cochlear, orthopedic, and other implanted medical devices.