Cancer cell separator using size-dependent filtration in microfluidic chip

We have developed a microfluidic chip that can separate gastric cancer cells from peritoneal washes. Gastric cancer cells tend to be agglomerated in the peritoneal wash, and are larger than the other cells and the soft tissue fragments. This paper presents a novel microfluidic chip to enrich low-concentrated cancer cells from the peritoneal wash by size-dependent cell filtration. This microfluidic chip has the advantage that it can separate agglomerated cells in high speed because larger objects are filtered by a gap in the microchannel. Two-step exposure was performed to fabricate a precise uneven channel for cell filtration. The main and shallow channels have heights of 100 μm and 8 μm, respectively. Furthermore, inserting fins in the microchannel that assist sheath flow enhanced continuous and robust separation against flow fluctuation in the microchannel. The microfluidic channel was designed to have high filtration efficiency and a high throughput while having a compact profile. We used patient's peritoneal washes to isolate cancer cells. As a result, we were able to enrich the cancer cells in peritoneal wash.