Blood Cell Counter in Gravity-Driven Microchannel

A three-pronged microchannel is fabricated in resin by UV laser ablation. A number of heat-hardened resin films are layered on a soda glass. A laser fabricates a part of the channel on each film for every lamination. The channels are 45 µm in depth and 50–150 µm in width. Through holes are made in the laminate film with a laser. Inlet pipes with reservoirs are inserted into the holes. A blood cell can be transported by gravity applied to it. The blood is led into the center of the channel with a sheath flow of solution from both side channels. Blood cells are then focused at the junction by controlling the height difference between a blood reservoir and the solution reservoirs.