Low temperature plasmas – ionized gases – operating at atmospheric pressure are a copious source of reactive oxygen and nitrogen species (RONS). Plasma-produced RONS have the ability to combat antimicrobial resistant bacteria and serve as a novel approach to cancer treatment. Reduction-oxidation (redox) processes play a major role in the cellular life cycle and are the metabolic driving force for aerobic biology. Plasma-induced redox chemistry in cells can potentially regulate these processes. This project will investigate the capability of plasma for control of biofilms – coordinated functional communities of bacteria. Physically removing biofilms can be extremely difficult, and antibiotics and topical decontamination products are largely ineffective due to multipronged biofilm defenses. The control of biofilms has become a grand societal challenge due to their exceptionally broad range of use and impact, from environmental engineering to biomedical applications. As an example, biofilm induced corrosion is a severe problem for world maritime industries. Biofilms and antimicrobial resistance are also major issues in the food industry and in medicine. Antimicrobial resistance is predicted to become the number one health problem in 2050 and the Centers for Disease Control and Prevention reports that every 15 minutes one person in the US dies because of an infection that antibiotics cannot treat effectively. Although the consequences of biofilms are typically thought of as being negative, biofilm bacteria are also extensively used in bioreactors with beneficial applications ranging from water remediation to energy harvesting. This project combines several research advances in plasma science, microbiology and engineering – each significant in their own right – into a convergent, transformative project to investigate fundamental plasma-induced biofilm processes.
The goal of the project is to develop the science required to understand the impact of plasmas on communities of living cells. Plasma treatment of organisms can produce non-local effects and systemic responses which are currently not understood. In complex organisms, such as animal models, it is difficult to quantify both the initiating plasma dose to individual cells and to diagnose consequences of the exposure – components of animal models are simply too inter-related. The proposed research will address the critical need to quantify plasma effects on organisms by developing the science required to obtain a fundamental understanding of plasma interactions within a biofilm – a simpler system of communicating organisms that allows access to diagnostics and modeling. Furthermore, model biofilm bacteria (e.g. Pseudomonas aeruginosa) are genetically tractable, lending themselves to detailed studies of plasma-induced effects at a molecular level. This improvement in understanding of systemic effects of plasma will be accomplished by investigating the biological response of plasma-treated, biofilm-associated, bacterial cells and their intercellular communication through the extra-cellular environment. The project will develop this new and convergent research frontier, combining plasma science, microbiology, and state-of-the-art printing methodologies, using biofilms as a model system. While initially focusing on global biofilm response to the plasma treatment, the project will advance plasma and 3D printing frontiers to develop highly controlled spatially-resolved experiments that could ultimately enable the treatment of a single bacterium cell in a biofilm and track the associated local and non-local biological impacts. The societal benefits of this research will be the ability to manipulate the growth and character of biofilms – for example, to eliminate biofilms where they are not desired, or to enhance their proliferation where biofilms are a desired product.
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.
