Integrated Microfluidic Chip for Efficient Isolation and Deformability Analysis of Circulating Tumor Cells

Efficient isolation and downstream analysis of circulating tumor cells (CTCs) beyond counting is challenging. Here, an integrated microfluidic chip for efficient isolation and deformability analysis of CTCs is reported. The microfluidic chip integrates two modules: one module is two mirrored deterministic lateral displacement (DLD) arrays for the depletion of blood cells; the other module is another DLD array with an increasing tilt angle for CTCs separation based on size and deformability. The chip allows continuous isolation of CTCs with >90% capture yield and >50% capture purity at a throughput of 12 mL h⁻¹. Results show that the captured cancer cells maintain good viability. Downstream deformability analysis validates that invasive MDA-MB-231 cells are more flexible than noninvasive MCF-7 cells. The deformability of CTCs isolated from cancer patient samples is highly heterogeneous. The implementation of cell deformability analysis integrated with microfluidics extends the laboratory capability beyond simple counting of CTCs.