Figure 2.

Schematic (a) top and (b) section views of the microfluidic chip used for cell counting (schemes are not scaled). The width w of the channel is 250 μm, and the height of the two layers h₁ and h₂ is 160 and 30 μm, respectively. The total length L is 9 mm, while the length of the thinnest part d of the chip is 1 mm. The latter corresponds to the observation area for counting the cells flowing in the microchannel within PBS. Light blue color indicates the microchannel, while orange circles represent the flowing cells. The white rectangle in (a) is the PDMS chip. Black arrows indicate the flow direction inside the microchannel, from the inlet to the outlet. (c) Picture of the final microfluidic chip made on PDMS and with PTFE capillaries fixed using epoxy glue.