Circulating tumor cells are increasingly recognized as predictive biomarkers in early cancer detection; therefore, detecting circulating tumor cells in the peripheral blood of patients has important implications for clinical applications, which include early cancer detection as well as diagnoses and prediction of cancer progression. If viable unmodified circulating tumor cells can be separated from whole blood, then subsequent clinical analysis of these cells can lead to personalized cancer treatment. However, due to the extreme rarity of circulating tumor cells, a successful separation technology must meet the performance metrics of high-throughput, high-sensitivity, high-purity, and high-viability simultaneously to be useful - a goal that has never been achieved. To tackle these performance metrics, this project utilizes a novel threefold method called Three-Dimensional Deterministic Dielectrophoresis. Currently, the combined effects of three-dimensional geometry, deterministic lateral displacement and dielectrophoresis in a cell separation process represent a gap in research. Through this research, comprehensive understanding of the interplay between fluid mechanics, cell deformation, dielectrophoretic forces, and deterministic lateral displacement structures will be gained, which will lead to much improved sensitivity, purity, and cell viability at high-throughput - all requirements to be met at the same time. Additionally, the project will have a significant impact on a large number of underrepresented students in technical fields at both University of Illinois at Chicago (a federally designated Minority Serving Institution) and Washington State University Vancouver (a Research in Undergraduate Institutions eligible institution and the only four-year research university in southwest Washington).
The Three-Dimensional Deterministic Dielectrophoresis method brings a transformative impact by creating meaningful and valuable links between previously unconnected ideas and domain knowledge - namely deterministic lateral displacement, dielectrophoresis, and three-dimensional printing - potentially disrupting and outperforming all existing alternatives. However, in order to make the method truly useful for medical practice, fundamental knowledge about the separation process must be gained. This breaks down into three research objectives: 1) Study cell transport, cell-obstacle collision dynamics, and cell dielectrophoresis in periodic obstacle arrays using predictive models with experimental validations; 2) Fabricate Three-Dimensional Deterministic Dielectrophoresis devices and characterize how different obstacle shapes, geometries, obstacle array patterns, dielectrophoresis field parameters, carrier fluids and flow rates influence the cell separation performance; 3) Characterize circulating tumor cell separation performance for lung tumor cells against the four performance metrics above. This proposed research is significant because the multiphysics numerical models will elucidate scientific mechanisms of the complex separation principles of this method, which will guide experimental realization of a microfluidic device for high-throughput label-free circulating tumor cell separation. The research is unique in that dielectrophoresis will be combined with deterministic lateral displacement in a three-dimensional micro-structure for the first time, which is enabled by state-of-the-art nano three-dimensional printing technology. The research outcomes here have important implications for clinical applications including early cancer detection as well as diagnosis and prediction of cancer progression, as circulating tumor cells are increasingly recognized as predictive biomarkers in early stage cancer.
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.
