centrifugal separation chamber 8 has an outlet passageway 10 with a check valve permitting one way flow of liquid from the centrifugal separation chamber the centrifugal separation chamber 8 has an inlet port 12 for introducing plasma cell mixtures such as whole blood and an air vent 14 to permit escape of air displaced by liquid as it is introduced through the inlet port 12 the inlet port 12 can be adapted for junction with a syringe and have a luer fitting the inner wall 6 defines a concentrating chamber 16 in the embodiment of fig1 the concentrating chamber is enclosed within the centrifugal separation chamber and can be axially concentric therewith it will be readily apparent to a person skilled in the art that the shapes can be cylindrical or other shapes and the relationships between these chambers can be axially concentric or other relationships without departing from the invention all of these shapes and relationships are intended to be within the scope of this invention a plunger 18 is positioned in the concentration chamber for motion along its central axis and the central axis of the concentration chamber the plunger is connected to a plunger actuator 20 which extends outside of the concentration chamber for manual or robotic movement of the plunger in the bead chamber portion 21 of the concentrating chamber volume 16 defined by the plunger 18 and the filter 26 are positioned desiccated hydrogel beads 22 and an agitator 24 the hydrogel beads are insoluble beads or disks which will absorb a substantial volume of water and not introduce any undesirable contaminant into the plasma they can be.