Method and apparatus for isolating platelets from blood

Blood platelet collection equipment containing a centrifugal rotation separation container with the cave which has the vertical inner surface. Float in a cave has the blood platelet collection surface on the base and the base, and the outside surface. Float density is lower [than the density of red corpuscles] higher than the density of plasma. When hanging in the blood in which float was separated, the blood platelet collection surface is on float, and has a position which places it below the height of blood platelets. Into centrifugality, the layer of blood platelets or a baffy coat adjoins the blood platelet collection surface immediately, and gather. Blood platelets are removed from the blood platelet collection surface next. The blood platelets by which the movement toward float which has larger density than all the blood through the red corpuscles under precipitation was captured are emitted, and blood platelet yield is raised.