Breaking the barrier: disruption of bacterial biofilms using microwave radiation

Biofilms are microbial consortia encased in the extracellular matrix that pose severe threats in healthcare and environmental settings due to their resistance to antimicrobials and their role in persistent infections. These structured communities colonize medical devices (e.g., catheters, implants) and contribute to nosocomial infections. Critically, biofilm-laden medical waste acts as a reservoir for multidrug-resistant pathogens and facilitates horizontal gene transfer, perpetuating antimicrobial resistance (AMR). Improper disposal risks environmental contamination, enabling pathogens to infiltrate water systems, soil, and food chains, exacerbating public health crises. Conventional methods like chemical disinfection or UV treatment often fail to dismantle biofilms, leaving viable pathogens to disseminate. In the present work, we have established the use of microwave radiation as an effective alternative strategy for pre-disposal sterilization of Escherichia coli UTI89 biofilm on different surfaces. In our results, 15 minutes of microwave exposure significantly reduced cell viability by up to 95% and regrowth potential by up to 25% of E. coli UTI89 biofilms formed on coverslips and catheter-mimicking surfaces. Microwave-treated biofilms showed marked structural disruption and increased membrane permeabilization, as confirmed by FE-SEM and CLSM analyses. These findings highlight microwave radiation as a promising strategy for efficient pre-disposal sterilization and mitigating environmental risks associated with biofilm-derived pathogens in healthcare waste. These findings support the use of microwave exposure as an innovative approach for sterilizing medical waste and controlling biofilm-associated pathogens, aligning with current global efforts to identify sustainable alternatives for infection control. Overall, our results indicate that microwave radiation could be implemented as an innovative strategy for effective pre-disposal sterilization, reducing the risks of environmental AMR dissemination from medical waste, and curbing biofilm-derived pathogens in landfills and water systems. We firmly believe that implementing our approach in conjunction with current modalities in clinical workflows could reduce device-related infections and help alleviate the burden of AMR.