Abstract: The present invention relates to a system for controlling the movement or transport of objects such as cells and other particles in a moving liquid stream. More particularly the invention relates to a system including a vacuum pump which pulls the sheath fluid from an open supply reservoir through a flow cell assembly where cell analysis occurs and discharges the flow cell effluent to an open waste reservoir. A pressure drop is created through the conduit leading from the supply reservoir to the flow cell which aspirates the cell suspension from an open sample vessel into and through the flow cell. The vacuum is regulated by controlling the electric power applied to the vacuum pump motor. Starting, stopping, reverse flushing, and draining of the flow cell assembly are controlled by programming the operation of four electric solenoid valves in fluid communication with the flow cell inlet and outlet passages, the operation of a reverse flush pump and, the operation of an electrically controlled tube lifter.

Abstract: A flow apparatus for the analysis of particles passing with a liquid substantially one at a time through an analysis region includes a backflow isolator and capture system to catch any liquid and particles dripping from the analysis region. The backflow isolator and capture system is activated by an unlocking support for the sample test tube carrying the supply of liquid and particles. The support is also an operator for a pump and a pressure vent valve whereby liquid, particles and aerosols cannot escape. A method for isolating and capturing backflow of a supply of particles to be analyzed includes steps of venting the air supply, moving a test tube support and activating a pump.

Abstract: Devices are disclosed which are useful in the simultaneous separation and filtration of the liquid portion of clotted whole blood and anti-coagulant treated whole blood. The devices are employed in novel apparatus of the invention, for the collection, separation and filtration of blood serum and blood plasma from clotted whole blood and anti-coagulant treated whole blood, respectively.