ERI: Magnetic nanoparticles to fight biofilms

University Of Rhode Island, Kingston RI

Investigators

Abstract

Bacteria often grow in dense, sticky colonies on surfaces, called biofilms. Biofilms can grow on diverse surfaces, such as medical implants, food containers or boat hulls. Unfortunately, biofilms can cause issues, and their removal can be difficult. For example, in the case of structures or parts of boats that are underwater, divers need to scrub the underwater surfaces. This research proposes using magnetic fields and magnetic nanoparticles to remove biofilms from a distance. Magnetic nanoparticles under the action of magnetic fields that alternate direction will rotate and move to follow the magnetic field, generating mechanical forces and temperature increases. These two effects will be explored by using different magnetic nanoparticles and applied magnetic field combinations to remove biofilms of a model marine biofilm, and the approach will be tested in natural marine biofilms. This project has the potential to yield innovative biofilm-removal technologies for other sectors, including the food industry and healthcare, impacting societal wellbeing and the US economy. Additionally, the research will involve undergraduate minority students, fostering their scientific interests and opening doors for future scientific careers. Researchers will also create easy-to-understand demonstration kits for public distribution featuring magnetic nanoparticles interacting with magnetic fields. Bacterial biofilms have a wide range of negative impacts on the economy, society, and human health, such as food spoilage, damage to military vehicles, and infections associated with medical implants. Marine bacterial biofilms grow on various underwater surfaces, like boat hulls and bridge foundations, and can be detrimental for their performance. While physical methods are often needed to remove biofilms, these are not always possible or practical, especially in cases where expensive and risky diving operations are required to access underwater structures. This project will investigate the use of magnetic nanoparticles under alternating magnetic fields to remove marine biofilms. Laboratory grown C. marina biofilms will be used as a model. Different magnetic nanoparticle sizes, shapes and surface coatings will be tested against distinct alternating magnetic field regimes. The biofilm integrity will be evaluated by quantifying the microrheology of the biofilm before and after treatment using dynamic magnetic susceptibility methods, and by analyzing the spatial distribution of bacteria and extracellular polymeric substances using fluorescence imaging. Once an optimal regime for magnetic nanoparticle application and treatment has been established, this approach will be tested with natural marine biofilms. The project will include undergraduate students underrepresented in STEM fields, increasing their involvement in scientific research. Additionally, a demo kit will be created to showcase the potential applications of magnetic nanoparticles in biomedicine. The kit will be used in open public events to increase science literacy among the general population and to raise awareness of scientific progress. This kit will also be used in recruitment events among diverse populations, encouraging diversity and inclusion, generating excitement towards the pursuit of STEM careers. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.