(632d) Nanotopography Regulated Cell Sensing Nanomaterials

while the rapidly evolving nanotechnology has shown promise in healthcare, energy and many other fields, there is an increasing concern about the reversed health consequences of engineered nanomaterials for nanotechnology workers and consumers. The nanomaterials have higher surface area and increased surface reactivity, and become more toxic due to their persistence in tissues. To evaluate the toxicity, animal studies are necessary but expensive and facility limited; while the current in vitro models do not recapitulate in vivo cellular microenvironment and are not the substitute for animal studies. There is a critical need to develop an in vitro biomimetic platform for reliable and inexpensive toxicity testing and risk assessment of nanomaterials. Recent studies provide convincing evidence that nanotopography has profound influences on cell phenotype and function. Therefore, we engineered a combinatorial library of nanotopographies and investigated how the nanotopographies modulated cell behavior and enhanced cell sensing multi-walled carbon nanotubes (MWCNTs). Fibroblasts were sensitive to the nanotopography. When the spacing between the nanoscale features was small, the filopolia extended out on the top of the pillars. With an increase in the spacing, the cells could reach the bottom of the spacing, thus enlarging the cell-substrate interactions. The difference in cell sensing nanostructured substrate had an impact on arrangement of focal adhesions and F-actin fibers and the cellular and nuclear size, which also influenced the sensitivity of cell sensing MWCNTs. The combinatorial library of nanotopographies provides a high-throughput screening platform to optimize the nanotopography for the end application. The identified optimal nanotopography enhanced fibroblast sensing nanomaterials, i.e. WMCNTs in this study. A biomimetic cell-based platform integrated with the optimal nanotopography can be developed to assess toxicity of nanomaterials and advance over the “classic” cytotoxicology method.