US Patent 7976796 Centrifuge tube for separating and aspirating biological components

A centrifuge tube assembly includes an elongate tubular receptacle having a capped upper end. The capped upper end includes a single inlet/outlet port formed therethrough for communication with an interior of the tubular receptacle. A flexible aspiration pipe is communicably engaged with the inlet/outlet port for extending longitudinally through the cylindrical receptacle. A sealing diaphragm is attached to a distal end of the pipe. The diaphragm is longitudinally movable within the tubular receptacle and sealably interengages an interior wall of the receptacle. Biological products are introduced into and aspirated from the receptacle below the diaphragm by the fluid conducting pipe.