Abstract: A device and method for separating heavier and lighter fractions of a fluid sample. The device includes a flexible collapsible inner container disposed within a substantially rigid outer container. A closure seals the open top end of the outer container. A filter assembly is sealingly mounted to the open top end of the inner container. The filter assembly includes a filter that permits lighter fractions to pass therethrough, while substantially blocking the heavier fractions. The filter assembly further includes a filter support having a slit valve registered with the filter. The slit valve opens in response to fluid pressure created by the lighter fractions for permitting the lighter fractions to flow therethrough.

Abstract: A device and method for separating heavier and lighter fractions of a fluid sample. The device includes a plurality of constituents comprising a container and a composite element in the container. The composite element is a separator comprising at least two components and more particularly, a bellows with a seal body, a low-density float and a high-density ballast. A fluid sample is delivered to the container and the device is subjected to centrifugation whereby the centrifugal load causes the seal body of the separator to deform so that the separator migrates through the fluid sample and then stabilizes between the heavier and lighter fractions of the fluid sample. The seal body of the separator will resiliently return to its initial configuration upon termination of the centrifugal load such that the seal body sealingly engages the container and the composite element separates the heavier and lighter fractions of the fluid sample.

Abstract: A device and method for separating heavier and lighter fractions of a fluid sample. The device includes a plurality of constituents comprising a container and a composite element in the container. The composite element is a separator comprising a deformable bellows, a ballast mounted to the lower end of the bellows, and a float is engageable with an upper end of the bellows. A fluid sample is delivered to the container and the device is subjected to centrifugation whereby the centrifugal load causes the ballast to move toward the bottom of the tube and causes an elongation and narrowing of the bellows. The separator then moves down the tube and stabilizes in a position between the separated phases of the fluid sample. Termination of the centrifugal load enables the bellows to return to its original condition in sealing engagement with the walls of the tube.

Abstract: A device and method for separating heavier and lighter fractions of a fluid sample. The device includes a flexible collapsible inner container disposed within a substantially rigid outer container. A closure seals the open top end of the outer container. A filter assembly is sealingly mounted to the open top end of the inner container. The filter assembly includes a filter that permits lighter fractions to pass therethrough, while substantially blocking the heavier fractions. The filter assembly further includes a filter support having a slit valve registered with the filter. The slit valve opens in response to fluid pressure created by the lighter fractions for permitting the lighter fractions to flow therethrough.

Abstract: An assembly for collection of a blood sample includes a hydrophobic plastic tube and a non-exudable block or graft copolymer having a hydrophobic domain compatible with and interpenetrated in the matrix of the tube plastic and a hydrophilic domain which provides a hydrophilic interior wall surface to the container. The invention includes a method to make the container.

Abstract: An assembly for collection of a blood sample includes a hydrophobic plastic tube and a non-exudable block or graft copolymer having a hydrophobic domain compatible with and interpenetrated in the matrix of the tube plastic and a hydrophilic domain which provides a hydrophilic interior wall surface to the container. The invention includes a method to make the container.

Abstract: An injection molding method for forming an article having a receptacle with a coating on an interior surface includes providing an injection molding tool with at least one cavity in one part and at least one core pin projecting from a second part having an outside surface. The core pin is sized to fit within the cavity with a clearance thereby defining a cavity space. The injection molding tool has an open position wherein the core pin is withdrawn from the cavity and a closed position wherein the core pin is disposed within the cavity for defining the cavity space. The method further sequentially then includes moving the injection molding tool to the open position and applying a coating of a coating material to the outside surface of the core pin. The method further includes moving the injection molding tool to the closed position.

Abstract: A composition is provided for use, particularly in evacuated blood collection tubes, as a blood partitioning composition. The composition is useful in provididng cleaner serum or plasma samples for biochemical tests, including a wide range of drugs. The composition includes a balanced dual resin component which provides the desired hydrophobic property while simultaneously controlling viscosity and the specific gravity, which component is comprised of poly-alpha-pinene resin which provides good drug recovery but low density with a chlorinated hydrocarbon resin which provides the proper density level while maintaining the desired hydrophobic property of the resin blend. Thixotropic property is achieved by adding silica and network stabilizer in the composition.