Abstract
Studies have shown that primary tumor sites begin shedding cancerous cells into peripheral blood at early stages of cancer, and the presence and frequency of circulating tumor cells (CTCs) in blood is directly proportional to disease progression. The challenge is that the concentration of the CTCs in peripheral blood may be extremely low. In the past few years, several microfluidic-based concepts have been investigated to isolate CTCs from whole blood. However, these devices are generally hampered by complex fabrication processes and very low volumetric throughputs, which may not be practical for rapid clinical applications. This paper presents a high-performance yet simple magnetophoretic microfluidic chip for the enrichment and on-chip analysis of rare CTCs from blood. Microscopic and flow cytometric assays developed for selection of cancer cell lines, selection of monoclonal antibodies, and optimization of bead coupling are discussed. Additionally, on-chip characterization of rare cancer cells using high resolution immunofluorescence microscopy and modeling results for prediction of CTC capture length are presented. The device has the ability to interface directly with on-chip pre and post processing modules such as mixing, incubation, and automated image analysis systems. These features will enable us to isolate rare cancer cells from whole blood and detect them on the chip with subcellular resolution.
Dynamic Halbach array magnet integrated microfluidic system for the continuous-flow separation of rare tumor cells
