Engineered nanomaterials have demonstrated biomedical applications in diagnostics, imaging, and drug delivery. For widespread adoption of these technologies, potential adverse health effects in both the short and long-term should be thoroughly explored. Due to their novel nanoscale properties, the manner in which these nanomaterials interact with biological systems is complex and relatively unknown, and very few tools exist to accurately understand the fate of these nanomaterials in cells, animals and humans. This CAREER award will fund a research program that introduces a new imaging technique to more precisely describe the locations and numbers of nanomaterials within the confines of live cells. This research will generate new knowledge, where quantitative imaging data will be correlated to established measures of cell health, leading to a better understanding of nanomaterial-induced toxicity. The work will be closely integrated into an educational and outreach program that engages the local K-12 community with interactive seminars and hands-on laboratory experience investigating interactions at the nano-bio interface. Finally, the work will enable the formation of a highly interdisciplinary bionanotechnology course, with particular emphasis on nanotoxicology, to further stimulate and educate the STEM-focused workforce within Rhode Island. Together, these activities support the broader impacts and dissemination of the work by generating widespread interest in STEM and improved understanding of novel nanomaterial technologies.
Engineering nanomaterials for the purposes of creating novel diagnostic, imaging, and drug delivery devices has garnered significant attention within the past two decades. A recently discovered one-dimensional allotrope of carbon, the single-walled carbon nanotube, with intrinsic near-infrared fluorescence that is indefinitely photostable and environmentally sensitive, presents a unique opportunity to create sensing and imaging constructs as research tools for live cell and animal studies. As with all exogenously introduced materials, adverse effects to cell health in both the short and long-term should be thoroughly explored. In the case of carbon nanotubes, the nanomaterial is known to enter cells through receptor-mediated endocytosis and remain within the endosomal pathway. For widespread adoption of nanotube-based sensors and imaging probes in standard biological applications, detrimental effects to the vesicles involved in this pathway should be investigated. The research objective of this CAREER project, using a novel spectral imaging approach for sub-cellular measurements within live cells, is to quantify the number of nanotubes in diffraction-limited regions within a cell and determine how naturally aggregated nanomaterials influence toxicity in mammalian cells. The research project seeks to: 1) employ hyperspectral fluorescence microscopy to investigate the nanostability that engineered nanotubes of varying physical properties exhibit in biological media, 2) investigate how nanotube functionalization, concentration, and aggregation state can affect the uptake and endosome loading ratio (nanotubes per endosome) in mammalian cells, and 3) examine how endosome loading ratio influences natural endosomal maturation processes (vesicle trafficking, endosome-to-lysosome progression, etc.), and correlate this to various cell stress and toxicity assays. The transformative nature of this work stems from the ability to pose and answer outstanding questions of nanotoxicology at the single-cell and sub-cellular level in a new manner that does not necessitate labeling or perturbing the biological system at hand. By performing these assays, a framework of rules will be created that governs the manner in which mammalian cells interact with nanotubes of various physical natures. The work will be thoroughly incorporated into a K-12 educational and outreach program with interactive seminars and practical laboratory experience probing biophysical interactions at the nano-bio interface. Finally, the work will enable the formation of a highly interdisciplinary bionanotechnology course, highlighting topics in nanotoxicology, to further stimulate and educate the STEM-focused workforce within Rhode Island.
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.
