Polymers For Use In Centrifugal Separation Of Liquids

Abstract

Contemplated compositions and methods allow for in-situ formation of a rigid seal layer in a blood collection tube between a cell-depleted phase and a cell-enriched phase. Preferably, the seal layer is formed upon brief UV irradiation and comprises an acrylate, a methacrylate, an epoxy, a urethane, and/or a thiol-ene polymer.

What is claimed is: 
     
         1 . A blood collection tube for separation of whole blood into a cell-depleted phase and a cell-enriched phase comprising:
 a polymerizable composition having a predetermined density and flowability effective to allow sedimentation of the composition under a centrifugal force to a position between the cell-depleted phase and the cell-enriched phase; and   wherein the polymerizable composition has a composition effective to retain the predetermined flowability during heat sterilization, and to allow subsequent UV curing to a hardness of at least 10 on a Shore A hardness scale within ten minutes.   
     
     
         2 . The collection tube of  claim 1 , wherein the density is between 1.02 and 1.06 g/cm 3 . 
     
     
         3 . The collection tube of  claim 1 , wherein the polymerizable composition is polymerizable by UV curing to a polymer selected from the group consisting of an acrylate polymer, a methacrylate polymer, an epoxy polymer, a polyurethane, and a thiol-ene polymer. 
     
     
         4 . The collection tube of  claim 3 , wherein the polymerizable composition comprises at least one compound selected from the group consisting of a monofunctional acrylate, a bifunctional acrylate, a trifunctional acrylate, a tetrafunctional acrylate, and an acrylate containing oligomer. 
     
     
         5 . The collection tube of  claim 3 , wherein the polymerizable composition comprises at least one compound selected from the group consisting of a monofunctional methacrylate, a bifunctional methacrylate, a trifunctional methacrylate, a tetrafunctional methacrylate, and a methacrylate containing oligomer. 
     
     
         6 . The collection tube of  claim 3 , wherein the polymerizable composition comprises at least one compound selected from the group consisting of a polymer containing a terminal epoxy group, a polymer containing a pendant epoxy group, an epoxy-siloxane resin, an epoxy-polyurethane, an epoxy-polyesters, epichlorohydrin, a polyhydric diol, and a polyhydric polyol. 
     
     
         7 . The collection tube of  claim 3 , wherein the polymerizable composition comprises at least one compound selected from the group consisting of an aromatic isocyanate, an aliphatic isocyanate, a polymer comprising a terminal or pendant isocyanate group, a polymer comprising at least two hydroxyl groups, a polyhydric diol, and a polyhydric polyol. 
     
     
         8 . The collection tube of  claim 3 , wherein the polymerizable composition comprises at least one compound selected from the group consisting of an aliphatic monomeric polythiol, an aliphatic dithiol, a cycloaliphatic dithiol, an aromatic dithiol, a polymeric polythiol, an acrylate, a methacrylate, an alkenyl, and a cycloalkenyl. 
     
     
         9 . The collection tube of  claim 1 , wherein the composition further comprises a photoinitiator and an optional photoinhibitor. 
     
     
         10 . The collection tube of  claim 9 , wherein the photoinitiator is selected from the group consisting of a phosphine oxide photoinitiator, a ketone-based photoinitiator, and a benzoin ether photoinitiator. 
     
     
         11 . The collection tube of  claim 1 , wherein the polymerizable composition has a composition effective to retain the predetermined flowability during irradiation sterilization. 
     
     
         12 . The collection tube of  claim 1 , wherein the polymerizable composition further comprises silica. 
     
     
         13 . The collection tube of  claim 1 , wherein the polymerizable composition has a composition effective to allow curing without substantial cell entrapment. 
     
     
         15 . The collection tube of  claim 1 , wherein the hardness is achieved upon UV curing over a period of less than five minutes. 
     
     
         16 . The collection tube of  claim 1 , wherein the polymerizable composition has a composition effective to form a fluid-proof barrier between the composition and an inner wall of the collection tube. 
     
     
         17 . The collection tube of  claim 1 , wherein the polymerizable composition has a composition effective to allow sterilization without curing more than 40%.