<p>(a) The disc is loaded with DGM as the whole blood is introduced during disc acceleration. (b) RBCs sediment. Note that the siphons have a number of capillary burst valves. The upper capillary valve on the lower siphon prevents the DGM pre-priming siphon while the disc is stopped for blood loading. (c) Stratified blood in the chamber. Note that the plasma remains below the siphon crest points. (d) The disc is decelerated and the bulk liquid is displaced radially inwards and the siphon prime. The siphon priming is halted by the capillary burst valves. The siphons must be primed at a lower frequency (~2.5 Hz) than the nominal frequency (~15 Hz) to prevent the capillary valves from bursting early or out of sequence. However, due to the low hydrostatic priming pressure at this spin rate, the crest of the lower siphon required treatment using a surfactant to achieve reliable priming. The upper siphon was not treated. (e) The spin rate is increased and the burst valve of the upper siphon capillary is opened, thus removing the plasma to the collection chamber. (f) The spin rate is increased further and the lower siphon valve opens for removing the WBCs (with some plasma and DGM) to the WBC collection chamber. See ESI <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0155545#pone.0155545.s001" target="_blank">S1 Movie</a> showing blood processing in Disc C.</p
