Rotor with elastic diaphragm defining a liquid separating chamber of varying volume

Abstract

A rotor for collecting and centrifuging biological fluids in a range of volumes. The rotor includes an elastic impermeable diaphragm which defines at least a portion of a variable-volume processing chamber, where the fluid is centrifuged. The rotor includes a rigid mounting member, to which the diaphragm is mounted and which is held and spun by a chuck. Preferably, this rigid mounting member includes a boundary wall which together with the elastic diaphragm defines the chamber. The boundary wall may be a substantially imperforate circular wall which extends to the periphery of the processing chamber but defining one opening, preferably near the axis of rotation, permitting a conduit or conduits to pass therethrough so as to be in fluid communication with the processing chamber. The rotor may include a separate structure for controlling the flow of liquid out of the chamber into the conduit. In a preferred embodiment, this outlet-control structure is a perforate, substantially rigid wall or plate, located within the processing chamber and mounted adjacent the rigid boundary wall. In an alternative embodiment, the outlet-control structure for controlling flow from the processing chamber to the conduit may include at least one tube or preferably a set of tubes, wherein each tube provides fluid communication between the chamber and the conduit. In one preferred embodiment, grooves in the boundary wall may be used as the outlet-control structure.