Novel assembly for separating blood

Claim 1

An assembly for the collection, separation and isolation of serum or plasma from blood, which comprises; a. a tubular container having an open end and which defines a blood collection chamber; b. a self-sealing, cannula-penetrable, elastomeric closure member hermetically sealing said open end; c. a recess in the inner surface of said closure member; d. a thixotrope barrier dispenser secured in said recess, said dispenser comprising; i. a tubular body fabricated of hemorepellant material and having an open lower end which defines a thixotrope reservoir, said open lower end being insufficient in size to permit pasage of said thixotrope under the force of one gravity but of sufficient size to permit passage of said thixotrope when the thixotrope is subjected to a centrifugal force in substantial excess of one gravity; and ii. a conduit passing through the center of said reservoir and providing communication between the adjacent closure member and the blood collection chamber said conduit extending partially into said blood collection chamber; and e. a thixotrope sealant disposed in said reservoir, said thixotrope having a specific gravity within the range of from about 1.03 to about 1.09; said assembly being air-evacuated to provide at least a partial vacuum in said blood collection chamber.