Abstract
We developed a novel device which separates blood plasma from a minute amount of whole blood using tilted microchannels. Blood cell sedimentation is enhanced in a tilted channel, and its velocity is much larger than in a vertically-placed channel. This phenomenon is called the Boycott effect. The blood separation device had three microchannels which are made of PDMS and measure 100 μm in depth, and their ends were connected at one point. The two channels were tilted at a 45 degrees angle and used for blood separation. The other channel was placed vertically and used for blood sample injection. When a blood sample was placed at the entrance of the injection channel, the blood automatically entered the channels by capillary force. Then, blood cell sedimentation at the connection of the channels was observed using a CCD camera. The experimental results showed that the sedimentation velocity increased with an increase of length of the blood separation channel. We succeeded in obtaining a sedimentation length of 100 μm in 1.5 min using the 20 mm long separation channel.
