Abstract (non-technical) Advancements in microbial biotechnology continue to expand our knowledge of the bacterial world. To fully understand and predict behavior of bacteria, it is necessary to connect its molecular makeup with its observable characteristics. This often requires individual bacteria first be isolated at high purity, which is currently difficult to do. The goal of this NSF CAREER award is to investigate use of photodegradable hydrogel materials for identification and isolation of rare bacteria cells with unique function for molecular analysis. Hydrogels are three-dimensional, water-soluble polymers that can be used to encapsulate collections of cells for observation. A fundamental understanding of both chemical and physical characteristics of hydrogels that lead to stable and effective encapsulation of bacteria will first be established. These hydrogels will then be designed to degrade following exposure to low-energy, near-infrared light unharmful to bacteria, which will allow for release of live, single cells from the hydrogel at any time. The outcome will be a new, materials-based approach to microbial isolation that will be low cost and highly translational to the standard microbiology lab. These hydrogels will have broader application to other emerging areas in microbiology including targeted delivery of therapeutic bacteria to disease sites. The integrated educational goal of the project is to develop global-minded students who are well prepared for interdisciplinary research careers at the interface of materials science and microbiology through the Joint Microbe-Material Scholars (JMMS) program. The JMMS platform will leverage established programs at Kansas State University for engagement and recruitment of underrepresented minority students throughout the state of Kansas and will provide its scholars with international research experiences. This project is jointly funded by the Biomaterials Program of the NSF Division of Materials Research, and the Established Program to Stimulate Competitive Research (EPSCoR).
Abstract (technical) Photodegradable hydrogels have been intensively studied for application in tissue engineering and targeted drug delivery. However, these materials are largely unexplored for use in microbiology, but have great potential for on-demand delivery of bacteria as well as for use in low-cost cell isolation methods. These capabilities are critical for advancing our knowledge of the microbial world and for using bacteria in emerging therapeutic applications. The overall goal of this CAREER proposal is to provide a fundamental understanding of hydrogel material properties that provide stable bacteria encapsulation, culture, transport, and release from photodegradable hydrogels with high viability and precision. Step-growth polymerizations that use thiol-Michael addition reactions for bacteria encapsulation into stable, polyethylene glycol-based hydrogels will be identified, and the impact of hydrogel mesh size and elasticity on bacteria proliferation and transport will be investigated. Up-conversion nanoparticles will be integrated into the hydrogel matrix to investigate release of individual bacteria cells using a patterned NIR light source. Finally, these novel materials will be tested for isolation of rare bacteria with viable but nonculturable phenotypes for follow-up molecular analysis. Knowledge gained from these tasks will inform the rational design of hydrogels for isolation of single bacteria with unique function for 'omics'-based analysis and delivery of live, therapeutic bacteria to targeted disease sites. The research will be integrated into the educational plan through the Joint Microbe-Material Scholars program, an educational platform designed to produce global-minded, interdisciplinary students through four components: (1) an international student exchange with collaborators in food microbiology, (2) an external outreach mechanism designed to engage and recruit minority students throughout the state of Kansas, (3) a microbe-material course that uses an interdisciplinary guided-inquiry teaching method, and (4) public engagement. The PI will leverage successful programs at Kansas State University for reaching broader audiences including the Kansas-Louis Stokes Alliance for Minority Participation program, Project IMPACT, and Science on Tap.
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.
