An on-chip whole blood/plasma separator with bead-packed microchannel on COC polymer

A disposable on-chip whole blood/plasma separator, which is able to separate plasma from whole human blood by capillary force through a bead-packed microchannel, has been designed, fabricated and characterized in this work. Various sizes of silica beads were slurry-packed through a microchannel using a bump structure which held beads in a defined region. The bead-packed microchannel induces a capillary force which allows plasma to move forward through the bead-packed column more rapidly than red blood cells (RBCs). The blood/plasma separator with bead-packed microchannel has successfully separated plasma from the whole blood without haemolysis of RBCs. The separation method developed in this work can be applied to various on-chip stationary filtrations of RBC for point-of-care clinical diagnostics.