Isolation of circulating fetal trophoblasts by a four-stage inertial microfluidic device for single-cell analysis and noninvasive prenatal testing.

Noninvasive detection of circulating fetal cells carrying the entire fetal genome is a promising way for prenatal testing of genetic diseases. However, ideal approaches for efficient separation of these valuable cells are not available. Here, a novel inertial microfluidic chip (CelutriateChip 1) is developed for ultra-fast, label-free enrichment of circulating trophoblasts (CTBs) from the whole blood samples of pregnant women.

Spiral microchannel with rectangular and trapezoidal cross-sections for size based particle separation.

The paper reports a new method for three-dimensional observation of the location of focused particle streams along both the depth and width of the channel cross-section in spiral inertial microfluidic systems. The results confirm that particles are focused near the top and bottom walls of the microchannel cross-section, revealing clear insights on the focusing and separation mechanism. Based on this detailed understanding of the force balance, we introduce a novel spiral microchannel with a trapezoidal cross-section that generates stronger Dean vortices at the outer half of the channel.