US5039401A — Blood collection and centrifugal separation devic…

Claim 1

Independent Claim 193 words

In a liquid phase separation device suitable for phase separation by centrifuging, comprising a chamber with a predetermined volume V, a longest dimension l, and at least one shorter dimension d; said chamber having at least a heavier phase-collecting portion and a lighter phase-collecting portion; means permitting liquid introduction into said chamber; and removing means for removing separated lighter phase out of said chamber after separation without decreasing the centrifugal force used to separate the two-phases; the improvement wherein said heavier phase-collecting portion and said lighter phase-collecting portion are disposed so that said longest dimension of said chamber is generally equal to the length of at least one of said collecting portions, and said dimension "d" extends from the lighter phase-collecting portion into said heavier phase-collecting portion, and wherein said removing means include valve means for passing said separated lighter phase out of said chamber only in response to a liquid head of pressure created by centrifugal force, whereby phase separation for a liquid volume of 500 μL can occur for a spin radius of about 2.5 cm, in less than 2 minutes using a centrifuging force no greater than about 30 g's.

Claim 2

Dependent Claim 193 words

In a liquid phase separation device suitable for phase separation by centrifuging, comprising a chamber with a predetermined volume V, a longest dimension l, and at least one shorter dimension d; said chamber having at least a heavier phase-collecting portion and a lighter phase-collecting portion; means permitting liquid introduction into said chamber; and removing means for removing separated lighter phase out of said chamber after separation without decreasing the centrifugal force used to separate the two-phases; the improvement wherein said heavier phase-collecting portion and said lighter phase-collecting portion are disposed so that said longest dimension of said chamber is generally equal to the length of at least one of said collecting portions, and said dimension "d" extends from the lighter phase-collecting portion into said heavier phase-collecting portion, and wherein said removing means include valve means for passing said separated lighter phase out of said chamber only in response to a liquid head of pressure created by centrifugal force, whereby phase separation for a liquid volume of 500 μL can occur for a spin radius of about 2.5 cm, in less than 2 minutes using a centrifuging force no greater than about 30 g's.

Claim 3

Dependent Claim 106 words

In a two-phase liquid separation device suitable for phase separation by centrifuging, comprising at least one chamber with a predetermined volume V, said chamber having a heavier phase-collecting portion, and a lighter phase-collecting portion; inlet means permitting liquid introduction into said chamber; and means for removing separated lighter phase out of said chamber including a valve constructed to open at centrifugal forces in excess of those used to separate the lighter phase from the heavier phase; the improvement wherein said device further includes means for opening and maintaining said valve open only in response to a liquid head of pressure created by said excess centrifugal forces.

Claim 4

Dependent Claim 106 words

In a two-phase liquid separation device suitable for phase separation by centrifuging, comprising at least one chamber with a predetermined volume V, said chamber having a heavier phase-collecting portion, and a lighter phase-collecting portion; inlet means permitting liquid introduction into said chamber; and means for removing separated lighter phase out of said chamber including a valve constructed to open at centrifugal forces in excess of those used to separate the lighter phase from the heavier phase; the improvement wherein said device further includes means for opening and maintaining said valve open only in response to a liquid head of pressure created by said excess centrifugal forces.

Claim 5

Dependent Claim 35 words

A device as defined in claim 2, wherein said opening and maintaining means is constructed to close said valve in the absence of liquid pressure, regardless of the magnitude of the centrifugal force during centrifuging.

Claim 6

Dependent Claim 94 words

A device as defined in claim 3, wherein said valve includes biasing means to bias the valve closed, said biasing means being operative in a direction that is substantially perpendicular to the direction of force of said centrifuging, with a biasing constant adjusted to open said valve in response only to a predetermined liquid head of pressure, so that said valve opens and stays open only as long as a liquid head of pressure is present because liquid is pressing against said valve, even when high centrifugal forces are applied in said perpendicular direction.

Claim 7

Dependent Claim 14 words

A device as defined in claim 4, wherein said valve is a ball valve.

Claim 8

Dependent Claim 82 words

A device as defined in claim 1 or 2, wherein said valve comprises a valve seat, a closure member, and biasing means for biasing said closure member against said valve seat in opposition to fluid flow through said valve, said biasing means comprising a cellular foam having a Young's modulus of no larger than about 345 kilopascals, said closure member being selected from an impervious, non-sticking, dimensionally stable material that is sufficiently flexible and thin as to conform to said valve seat.

Claim 9

Dependent Claim 24 words

A device as defined in claim 6, wherein said material of said closure member comprises a polymer tape no thicker than about 0.2 mm.

Claim 10

Dependent Claim 50 words

A device as defined in claim 7, wherein said closure member comprises a polymer tape selected from the following polymers and the following maximum thickness: ______________________________________ cellulose acetate 0.10 mm polyethylene 0.20 mm polyester 0.15 mm polyester silvered 0.15 mm on one side polytetrafluorethylene 0.15 mm polycarbonate 0.15 mm. ______________________________________

Claim 11

Dependent Claim 43 words

A device as defined in claim 1, 2 or 3, wherein said liquid is whole blood and said lighter phase is serum or plasma, and further including means for withdrawing and trapping residual blood cells left in said lighter-phase-collecting portion when centrifuging begins.

Claim 12

Dependent Claim 32 words

A device as defined in claim 1, 2 or 3, and further including in said chamber means for restricting separated heavier phase from remixing with said separated lighter phase after phase separation.

Claim 13

Dependent Claim 174 words

In a two-phase liquid separation device suitable for phase separation by centrifuging, comprising at least one chamber with a predetermined volume V, said chamber having a heavier phase-collecting portion, and a lighter phase-collecting portion; inlet means permitting liquid introduction into said chamber; and means for removing separated lighter phase out of said chamber including a valve constructed to open at centrifugal forces in excess of those used to separate the lighter phase from the heavier phase; the improvement wherein said device further includes means for opening and maintaining said valve open only in response to a liquid head of pressure and further including a second chamber having a heavier phase-collecting portion and a lighter phase collecting portion, said at least one chamber and said second chamber being disposed adjacent to each other, said chambers having a proximal end and a distal end, said chambers being fluidly connected in common to a) said inlet means at said proximal end and b) said removing means at said distal end, so that said chambers act in parallel.

Claim 14

Dependent Claim 174 words

In a two-phase liquid separation device suitable for phase separation by centrifuging, comprising at least one chamber with a predetermined volume V, said chamber having a heavier phase-collecting portion, and a lighter phase-collecting portion; inlet means permitting liquid introduction into said chamber; and means for removing separated lighter phase out of said chamber including a valve constructed to open at centrifugal forces in excess of those used to separate the lighter phase from the heavier phase; the improvement wherein said device further includes means for opening and maintaining said valve open only in response to a liquid head of pressure and further including a second chamber having a heavier phase-collecting portion and a lighter phase collecting portion, said at least one chamber and said second chamber being disposed adjacent to each other, said chambers having a proximal end and a distal end, said chambers being fluidly connected in common to a) said inlet means at said proximal end and b) said removing means at said distal end, so that said chambers act in parallel.

Claim 15

Dependent Claim 35 words

A device as defined in claim 11, wherein said chambers are defined by opposed surfaces spaced apart a capillary distance so that liquid entering said inlet means is drawn into said chambers by capillary attraction.

Claim 16

Dependent Claim 44 words

A device as defined in claim 12, wherein said opposed surfaces for each of said chambers are provided with grooves, the grooves of one surface of a chamber being disposed at an angle to the grooves of the other surface of the same chamber.

Claim 17

Dependent Claim 43 words

A device as defined in claim 11, and further including between said distal ends and said proximal ends, passageways connecting said chambers together to allow equalizing of pressure between said two chambers, so that said chambers fill together at an approximately equal rate.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1994-08-12	1995-02-11	1995-08-13	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1998-08-12	1999-02-11	1999-08-13	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2002-08-12	2003-02-11	2003-08-13	$7700.00	Window Closed / Lapsed

Blood collection and centrifugal separation device including a valve

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