Smart Materials: Harnessing Sound to Combat Bacterial Growth

Secondary Supervisor(s): Dr Tim Overton

University of Registration: University of Birmingham

BBSRC Research Themes: Understanding the Rules of Life (Microbiology)

Project Outline

Bacterial biofilms pose a significant challenge in healthcare and industrial settings, where they colonize surfaces such as implants, urinary catheters, food processing equipment, and pipelines. These biofilms are responsible for infections, contamination, clogging, and reduced operational efficiency. As biofilms adversely impact numerous human activities, their prevention and eradication have been the focus of intensive research for decades. Despite advancements, current strategies face limitations in their long-term efficacy against bacterial adhesion. For instance, the use of chemical antimicrobials can lead to the development of multidrug-resistant bacteria, posing severe risks to both human and animal health. Recent studies indicate that bacteria are sensitive to mechanical stimuli, revealing that vibrations can disrupt their adhesion and biofilm formation. However, existing methods rely on large, external equipment to generate vibrations, which limits their practical application.

The project aims to develop a self-sustaining solution by creating novel polymer materials that can harvest ambient acoustic energy—such as noise from hospital or industrial environments—and convert it into localised vibrations. These vibrations will inhibit bacterial attachment without the need for bulky external devices, offering a dynamic and non-chemical strategy to combat biofilm formation.

Objectives

• Generate acoustic energy-harvesting polymer materials that efficiently capture ambient acoustic energy and translate it into nanoscale mechanical vibrations.
• Combine these materials with nanostructured surfaces exhibiting inherent antibacterial properties. This integration aims to enhance bacterial disruption by applying dynamic mechanical stimuli alongside established static surface features.
• Investigate the responses of clinically relevant bacteria, such as Pseudomonas aeruginosa, to the vibrational stimuli generated by the material surfaces. This will involve examining biofilm formation, bacterial adhesion and mechanotransduction pathways.
• Develop prototypes for real-world applications: Translate these materials into practical prototypes for applications in medical devices, such as urinary catheters, and industrial equipment, including heat exchangers.

Employing a multidisciplinary approach that combines polymer chemistry, materials science, microbiology, and bioengineering, the project seeks to innovate acoustic energy-harvesting materials capable of preventing long-term bacterial adhesion. The materials will be created using polymerisation and self-assembly techniques, engineered to respond to ambient noise frequencies common in relevant settings. Mechanical testing will assess their effectiveness in converting acoustic energy into surface vibrations that disrupt bacterial adhesion. The project will further integrate these polymers with nanostructured surfaces designed to mimic natural antibacterial topographies, enhancing their efficacy against biofilm formation. Key structural and vibrational properties will be evaluated, ensuring efficient energy conversion that influences bacterial behaviour.

This project will open new avenues i) to combat biofouling of medical implants/devices, including urinary catheters that are resistant to colonisation, therefore reducing infections in hospitals; ii) to create antimicrobial surfaces for food processing to prevent spoilage or contamination of food and industrial equipment that resists bacterial attachment, which would increase process efficiency.

References

Nasim Mahmoodi, Dario G. Bazzoli, Tim W. Overton, Paula M. Mendes, “Plasma Activation and Its Nanoconfinement Effects Boost Surface Anti-Biofouling Performance”, Advanced Materials Interfaces, 2023, 10, 2202087.

Dario G. Bazzoli, Nasim Mahmoodi, Terri-Anne Verrill, Tim W. Overton, Paula M. Mendes, “Nano-vibrational stimulation of Escherichia coli mitigates surface adhesion by altering cells membrane potential”, ACS Nano, 2024, In Press.