Patent attributes
Systems and methods centrifugally separate whole blood into red blood cells, plasma, and a platelet concentrate. The systems and methods rotate a first rotating separation zone about a rotational axis, to separate whole blood into red blood cells and plasma constituent carrying platelets. Red blood cells separated are directed in a first circumferential flow direction toward a terminal wall, where blood flow is halted. Surface hematocrit is successively increased in the first circumferential flow direction by separating the plasma constituent from the red blood cells. Separated red blood cells are directed from the first rotating separation zone through a path where the surface hematocrit is the most. Plasma constituent separated is directed in a second circumferential flow direction opposite to the first circumferential flow direction toward a different region in the first rotating separation zone, where the surface hematocrit is the least. The systems and methods separate the plasma constituent into platelet concentrate and plasma in a second rotating separation zone.
