NSF Award
2102056
NON-TECHNICAL SUMMARY:<br/><br/>Infections by bacterial pathogens, especially those that are resistant to antibiotics, represent a major threat to the public health in this country, with millions of people suffering from the infections and a significant number of deaths each year. Thus, there are urgent demands for alternative approaches to prevent the spread of such infections. Nanomaterials-based approaches hold promise to serve as antibacterial agents against multidrug-resistant (MDR) bacteria. This collaborative project will develop and establish the newly discovered photoactive nanomaterials, specifically carbon dots (CDots) and derived “hybrid dots” (with other components), as a uniquely potent biomaterials platform for killing MDR bacteria. CDots are of a core-shell structure, each with a nanoscale carbon particle as the core and organic molecules as the coating on its surface (shell). When exposed to human-friendly visible/natural or ambient light, CDots generate radical-like species that are highly lethal to bacterial pathogens, making them excellent bio-nanomaterials for antibacterial applications. This project will use some new strategies to design CDots and hybrid dots to improve and optimize the antibacterial performance, with expected broad positive impacts to the control of MDR pathogens, and also to the training of students in the important biomaterials field.<br/><br/>TECHNICAL SUMMARY:<br/><br/>This collaborative project is to further develop and establish carbon dots (CDots) and derived hybrid nanostructures as a unique biomaterials platform for visible/natural or ambient light-activated potent antibacterial function. CDots may be considered as a special kind of “core-shell” hybrid nanostructures, each with a small carbon nanoparticle core and a thin shell of attached organic materials for the particle surface passivation. They are strongly absorptive in the visible spectrum, and their photoexcited state properties and processes resemble those typically found in semiconductor quantum dots, but with unique advantages. The versatility and flexibility of modifying the dot surface with organic moieties enable the manipulation of CDots to enhance their optical properties and their interactions with the targeted bacterial cells. The project team will leverage these distinctive characteristics to design and prepare CDots and derived hybrid nanostructures for the desired properties based on the rationales including 1) the more effective photon harvesting across the entire visible spectrum, 2) highly efficient photoexcited state processes responsible for the antimicrobial activities, and 3) more targeted and stronger interactions with the bacterial cells, thus to establish the CDots/hybrid dots as effective and efficient broad spectrum agents for killing multidrug-resistant pathogens. The efforts will be coupled with investigations for mechanistic understanding of these bio-nanomaterials. The project will also have broader impacts in terms of societal benefits and technology development, institutional research enhancement, education and engagement of undergraduate students in research, and outreach activities.<br/><br/>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.
