Abstract: An apparatus and method are disclosed to wash blood cells in a discrete manner that is compatible with automated sample preparation systems. The test tube containing the cells to be washed is mounted on a rotatable spindle. The spindle includes central passageways for the introduction of wash fluid and air into the test tube, and radial exit passageways at the bottom of the spindle. The test tube is first spun about its vertical axis to centrifuge cells against the inner wall of the test tube. A vacuum is then applied to the exit passageways so cell supernatant is aspirated out through the exit passageways. Wash fluid is then introduced into the test tube, and aspirated out through the exit passageways, thereby washing the cells. Rotational acceleration and deceleration of the test tube then resuspends the cells in wash fluid.

Abstract: An apparatus and method is disclosed for transferring biological fluids such as blood and serum from closed containers to multiple receiving containers. The disclosed methods and apparatus perform the transfer of an accurate and precise amount of biological liquid without dilution of the biological liquid, and without splattering of the biological liquid on the walls of the receiving container. Furthermore, the method discloses how to obtain equal concentrations of white blood cells in multiple receiving containers characteristic of their concentration in the sealed container.