Abstract: A blood collection and separator assembly capable of separating blood into its component parts of plasma or serum, the light phase, and cellular portion, the heavy phase, is disclosed. The assembly comprises a container having one open end for receiving blood and a two part barrier assembly slidably disposed in the container. The outer part or shell of the latter assembly has a specific gravity greater than the light phase of blood and the inner part or plunger has a specific gravity less than the heavy phase of blood. Interposed between the two parts is a viscous sealant, such as silicone grease. After the blood separates into its light phase and heavy phase under centrifugal force, the barrier assembly is introduced so it sinks to the interface between separated phases. Upon applying further centrifugal force, the inner plunger tends to move upward while the outer shell tends to move downward thus causing a squeezing action on the interposed sealant.

Abstract: A fractional-fill capillary pipette adapted to fill to a predetermined mark to obtain a desired known volume of liquid such as blood, plasma, test reagents or the like is disclosed. The bore of the capillary tube is provided with means to facilitate the filling of the capillary tube to the mark with a continuous column of liquid to obtain a predetermined known volume without the necessity of filling the entire capillary tube.

Abstract: A blood collection and separator assembly of the type suitable for use in centrifuging blood to separate the plasma or serum, the light phase, from the cellular portion, the heavy phase. The assembly includes a collection container and a piston disposed therein for sealing off one phase from the other after centrifuging is terminated. The piston is formed having an average specific gravity heavier than the light phase of the blood. The piston is slidably disposed in the container with its outer surfaces in sealing contact with the inner surface of the container and is provided with means which, under centrifugal force, permit the light phase of the blood to pass the piston as the piston moves down through the light phase while retaining sealing engagement with the inner surface of the container. The piston is provided with means to stop the piston at a predetermined distance above the bottom of the container whereupon the piston can serve as an impervious barrier between the two phases of the blood.

Abstract: An evacuated tube having both ends closed has a flap type valve fixedly disposed between the ends for dividing the tube into upper and lower chambers. The valve is formed and arranged to provide a passageway between the upper and lower chambers when subjected to centrifugal forces of proper intensity and direction. Upon cessation of the force, the valve closes to provide a separation between the upper and lower chambers.

Abstract: An evacuated tube having both ends closed has a centrifugally actuated slit type valve fixedly disposed between the ends for dividing the tube into upper and lower chambers. The valve is formed and arranged to provide a passageway between the upper and lower chambers when subjected to a centrifugal force of proper intensity and direction. Upon cessation of the force, the valve closes to provide a separation between the upper and lower chambers.

Abstract: An evacuated tube having both ends closed has a ball actuated resilient aperture type valve fixedly disposed between the ends for dividing the tube into upper and lower chambers. The valve is formed and arranged to provide a passageway between the upper and lower chambers when opened by the ball subjected to a centrifugal force of proper intensity and direction. Upon cessation of the force, the valve closes to provide a separation between the upper and lower chambers.

Abstract: A self-contained fluid separator assembly is disclosed capable of separating blood into its component parts of plasma or serum, the light phase, and the cellular portion, the heavy phase. The assembly comprises a container having at least one open end for receiving blood for subsequent separation and a closure sealing the open end of the container. The closure is formed of a self-sealing elastomeric material which is penetrable by a pointed hollow needle through which the blood to be separated is conducted into the container. A piston is slidably disposed in the container with its outer surfaces in sealing contact with the inner surfaces of the container. Centrifugally actuated valve means is provided on the piston which is normally closed and automatically opens in response to centrifugal force. When blood in the container is subjected to centrifugal force it first separates into its light phase and heavy phase.