U.S. patent number 3,850,174 [Application Number 05/341,044] was granted by the patent office on 1974-11-26 for plasma separator assembly.
This patent grant is currently assigned to Becton, Dickinson and Company. Invention is credited to Waldemar A. Ayres.
United States Patent |
3,850,174 |
Ayres |
November 26, 1974 |
PLASMA SEPARATOR ASSEMBLY
Abstract
An assembly adapted to receive blood for separation into a light
liquid phase of serum or plasma and a heavy phase is disclosed. The
assembly includes a self-sealing, pierceable, elastomeric
stopper-piston member which is capable of acting as a slidable
piston as well as a closure for holding a vacuum in an evacuated
container for collecting blood. Means is provided which is capable
of pushing the piston member downwardly in the container; the means
having a pointed tubular member associated therewith which is
capable of piercing the piston so as to provide a passage for
conducting the separated light liquid phase from one side of the
stopper-piston to the other side thereof.
Inventors: |
Ayres; Waldemar A. (Rutherford,
NJ) |
Assignee: |
Becton, Dickinson and Company
(East Rutherford, NJ)
|
Family
ID: |
23336029 |
Appl.
No.: |
05/341,044 |
Filed: |
March 14, 1973 |
Current U.S.
Class: |
604/415; 422/533;
215/247; 435/2; 435/307.1; 600/577; 210/513; 436/177; 422/918 |
Current CPC
Class: |
B01L
3/5021 (20130101); A61B 5/150389 (20130101); A61B
5/150496 (20130101); A61B 5/154 (20130101); A61B
5/150213 (20130101); A61B 5/150755 (20130101); A61B
5/15003 (20130101); A61B 5/150351 (20130101); A61B
5/150251 (20130101); Y10T 436/25375 (20150115) |
Current International
Class: |
A61B
5/15 (20060101); B01L 3/14 (20060101); A61b
005/14 () |
Field of
Search: |
;128/276,DIG.5,272,2F
;23/258.5,259,23B,292 ;233/26 ;215/47 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Gaudet; Richard A.
Assistant Examiner: Recla; Henry J.
Attorney, Agent or Firm: Kane, Dalsimer, Kane, Sullivan and
Kurucz
Claims
What is claimed:
1. An assembly for collecting blood and anti-coagulant treated
blood and for separating said blood into its light liquid phase and
its heavy, substantially cellular phase which comprises;
a blood collection container having at least one open end;
a stopper-piston slidably mounted in said open end made of a
self-sealing, elastomeric, pierceable material which functions as a
stopper to seal said open end of said blood collection container
when emplaced therein and which functions as a piston when moving
from its position at the open end of said container to a position
within said container which is intermediate to the ends
thereof;
said stopper-piston having;
i. a lower tubular body portion having sliding-sealing means
positioned around the outer periphery thereof and integrally formed
therewith, said tubular body portion with sealing means being of a
dimension such that when inserted in said container, a sliding seal
is made with the inner walls of said container; and
ii. an upper solid body portion having integrally formed means on
the outer periphery thereof for (a) engaging the rim of the open
end of said container when the stopper-piston functions as a
stopper and for (b) forming a seal with the inner walls of said
container when the stopper-piston functions as a piston; and
means for sliding said stopper-piston downwardly into said
collection chamber when it contains blood separated into its light
and heavy phases, so as to establish an impermeable barrier
separating the light liquid phase from the heavy phase of blood
which comprises a pusher having,
A. a blunt end for pressing against the upper surface of said
stopper-piston; and
B. a tubular member mounted at said blunt end and being capable of
piercing said stopper-piston to form a passage therethrough, said
tubular member having open ends so that upon piercing said
stopper-piston there is fluid communication via said member between
the upper and lower surfaces of the stopper-piston and whereby an
axial force exerted against said pusher will cause the light phase
to be conducted through the tubular member, enabling the
stopper-piston to move downwardly.
2. The assembly of claim 1 wherein said stopper-piston includes a
tubular body portion having a diameter less than the inner diameter
of said blood collection container and a plurality of
circumferentially spaced rings integrally formed around the outer
periphery thereof; said spaced rings comprising the sliding-sealing
means.
3. The assembly of claim 1 wherein said tubular body portion is
formed having three spaced lobes so that when said stopper-piston
is mounted in the open end of said blood collection container, said
lobes will compress inwardly toward the axis of the stopper-piston
to provide three supporting contact areas to maintain the
stopper-piston in axial alignment when an axial force is exerted
against the piston to move the piston downwardly into the
container.
4. The assembly of claim 3 wherein said three lobes are separated
120.degree. each lobe being separated by a venting channel the
sides of which are defined by the end surfaces of the adjacent
lobes, the base of said venting channel being inclined with respect
to the longitudinal axis of said tubular body portion.
5. The assembly of claim 4 wherein the base of the venting channel
is inclined 45.degree.; the upper and outer edge portion of which
terminates adjacent said sealing ring formed on said tubular body
portion.
6. The assembly of claim 1 wherein a cap is removably mounted over
the end of the blood collection container containing the
stopper-piston so as to maintain the assembly in aseptic
condition.
7. The assembly of claim 6 wherein the cap is made of elastomeric
and pierceable material, said cap having a deformable skirt portion
capable of forming a compressive fit over the open outer end of
said container.
8. For collection, separation and storage of blood plasma and blood
serum, an assembly comprising:
A. an evacuated tubular container having one end open and the other
end closed;
B. a stopper-piston slidably mounted in said open end; said
stopper-piston being adapted to both maintain a vacuum within said
assembly prior to being filled with blood and being adapted to
slide downwardly into the container upon application of axial
pressure so as to establish an impermeable barrier substantially
between the separated serum or plasma and cellular phases of blood;
said stopper-piston comprising a self-sealing, elastomeric,
pierceable material having (i) a lower tubular body portion having
sliding-sealing means positioned around the periphery thereof and
integrally formed therewith, said tubular body portion with sealing
means being of a dimension such that when inserted in said
container, a sliding seal is made with the inner walls of said
container; and (ii) an upper solid body portion having integrally
formed means on the outer periphery thereof for engaging the rim of
the open end of said container so as to maintain a vacuum within
said assembly prior to being filled with blood; and
C. means for sliding said stopper-piston downwardly into said
collection chamber when it contains blood separated into its light
and heavy phases, so as to establish an impermeable barrier
separating the light liquid phase from the heavy phase of blood
which comprises a pusher having,
i. a blunt end for pressing against the upper surface of said
stopper-piston, and
ii. a tubular member mounted at said blunt end and being capable of
piercing said stopper-piston to form a passage therethrough, said
tubular member having open ends so that upon piercing said
stopper-piston the tubular member provides fluid communication
between the upper and lower sides of the stopper-piston and whereby
an axial force exerted against said pusher will cause the light
phase to be conducted through the tubular member, enabling the
stopper-piston to move downwardly.
9. The assembly of claim 8 including a sealing cap member adapted
to close said tubular container to contain the serum or plasma
within the tube and between the stopper-piston and the cap
member.
10. The assembly of claim 8 wherein said stopper-piston has at
least one air channel for use during manufacture of the assembly
whereby the stopper-piston may be partially inserted in the tubular
container and the assembly be placed within a chamber, subsequently
evacuated, said air channel enabling the air within the container
to flow out, with the stopper-piston later being pushed farther
into the container thereby sealing off the air channel and
thereafter maintaining the vacuum until the assembly is used.
11. The assembly of claim 10 wherein said stopper-piston has three
air channels located substantially 120.degree. apart.
12. The assembly of claim 9 wherein said sealing cap member has a
portion of its skirt with a smaller diameter than the skirt
opening.
Description
BACKGROUND OF THE INVENTION
The present invention relates to an assembly for the separation of
blood into its component phases of serum or plasma and cellular or
solid phase. Various devices are known and are used for separating
blood into its component phases. It is clinically desirable to
isolate the liquid phase from the solid phase of blood to prevent
chemical interaction between the separated cellular portion and the
plasma or serum. Several of the devices presently used are
disclosed in U.S. Pat. Nos. 3,355,089; 3,481,477; 3,508,653 and
3,512,940.
The present invention proposes to improve upon these devices which
are used for the separation of blood into its component phases.
SUMMARY OF THE INVENTION
The invention generally contemplates the provision of an assembly
adapted to receive blood for separation into a light liquid phase
of serum or plasma and a heavy phase. The assembly includes a
self-sealing pierceable, elastomeric stopper-piston member which is
capable of acting as a slidable piston as well as a closure for
holding a vacuum in an evacuated container for collecting
blood.
Means is provided which is capable of pushing the stopper-piston
downwardly into the container while at the same time a pointed
tubular member associated with the means penetrates the
stopper-piston to form a passageway therethrough to permit the
plasma-serum to be conducted through the passageway thereby
enabling the stopper-piston to be moved downwardly through the
light phase to just above the heavy phase of blood. After the
downward movement of the stopper-piston is completed the pointed
tubular member is removed from the slef-sealing pierceable
stopper-piston to form an impermeable barrier between the light
phase and the heavy phase of blood.
It is an object of the invention to provide a stopperpiston which
is capable of closing the open end of a blood collection container
and seals the container to maintain a vacuum therein.
Another object of the invention is to provide a serumplasma
separator assembly having a self-contained slidable member which
will act as a closure element prior to use and a piston when in
use.
Another object of the invention is to provide an assembly for
separating the serum-plasma phase from the cellular phase said
assembly including a blood container, a stopper-piston and a
sealing cap, whereby the serum plasma is contained in a first
chamber including the blood container, the stopper-piston and the
sealing cap, and the cellular phase being contained in a second and
separate chamber including the blood container and the
stopper-piston so that the container can be inverted, handled
roughly or shipped without spilling any of the contents or without
remixing the serum-plasma and cellular phases.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a compressed elevational and partially sectional view of
the blood collection assembly fitted with the stopper piston of the
invention herein and a cap for sealing the tube prior to use.
FIG. 2 is a sectional elevational view of the stopper piston.
FIG. 3 is a bottom view of the stopper piston as shown in FIG.
1.
FIG. 4 is a sectional elevational view of a cap for enclosing the
stopper piston as in FIG. 1 and for closing the open end of the
collection container as illustrated in FIG. 8. FIG. 5 is a
sectional elevational view of the blood collection assembly
illustrated in FIG. 1 prior to inserting the piston-closure all the
way into the open end of the container.
FIG. 6 is an elevational sectional view which illustrates the
collection of blood using the device of FIG. 1.
FIG. 7 is an elevational sectional view of the assembly of FIG. 1
in which the stopper-piston has been moved downwardly through the
separated liquid phase.
FIG. 8 is an elevational sectional view of the blood collection
container after the serum or plasma has been separated from the
cellular phase and the means for pushing the piston to the
interface has been removed and the cap (of FIG. 4) has been placed
over the upper end of the blood container tube to seal in the light
phase of the blood.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
For a better understanding of the invention reference is had to the
drawings which illustrate the various elements of the blood
collection and separator assembly. In FIG. 1 a blood collection
assembly 10 includes a blood collection container 12 generally made
of a transparent material such as glass or a transparent plastic
material which is inert to blood or any of its components,
anticoagulants or other chemicals used in connection with the
collection, storage or analysis of blood.
Stopper-piston 14 is removably mounted in the open end of container
12 and provides an interference fit capable of maintaining a vacuum
until the blood sample is collected. A cap 16 which is designed to
enclose the stopper-piston end of the collection container is
provided to maintain sterility of the exposed outer surface 15 of
stopper-piston 14 until the device is used. Cap 16 is molded as a
unitary structure and is preferably formed of a material which is
capable of being pierced by a pointed tubular member and is
sufficiently elastic to provide a compression fit when mounted in
position as seen in FIG. 1. Cap 16 may be made of an elastomeric
material, such as rubber, natural or synthetic. Attached to the
closed end 17 of cap 16 is skirt 18. Skirt 18 is formed having a
concave surface 19 and is sufficiently deformable to provide a
compression fit to hold cap 16 in place as seen in FIG. 1.
Stopper-piston 14 is made of a self-sealing, pierceable,
elastomeric material inert to and unaffected by blood or other
parenteral fluids and chemicals associated with the collection
thereof. Examples of such a material may be natural or synthetic
rubber. Stopper piston 14 includes a tubular body portion 11 having
a diameter slightly smaller than the internal diameter of container
12. A plurality of sealing rings 22 is integrally formed with body
portion 11, the sealing rings having a diameter slightly greater
than the internal diameter of container 12 so that when body
portion 11 is inserted into container 12 the sealing rings exert
compressive forces against the inner wall of container 12
sufficient to hold and maintain a vacuum prior to the collection of
blood.
Stopper-piston 14 is formed having an enlarged solid top rim
portion 13 integrally formed with the upper end of a tubular body
portion 11. The diameter of top rim portion 13 is greater than body
portion 11 and substantially equal to the external diameter of
container 12. Rim portion 13 is resilient and is capable of flexing
when a sufficient force is applied to stopper-piston 14 as
illustrated in FIG. 7. Body portion 11 of stopper-piston 14 is
trilobal and each lobe 23 is separated by a venting channel 20.
Base 21 of each channel is beveled inwardly to provide additional
elastomeric material to support and reinforce lowest seal ring 22.
The base 21 of channel 20 is preferably pitched at about 45.degree.
with the lobes 23 preferably spaced about 120.degree. apart. When
container 12 is being evacuated channels 20 provide air passages to
permit air to escape while stopper-piston 14 has been inserted part
way into container 12, as shown in FIG. 5. Also, since
stopper-piston 14 is trilobal rather than bilobal, stopper-piston
14 has less tendency to become tilted or cocked as it is being
moved into container 12 to engage sealing rings 22. Since
stopper-piston 14 remains in substantial axial alignment with
container 12 maximum contact is achieved between seal rings 22, the
top rim 18 and the inner wall surfaces of container 12. This
prevents any loss of vacuum or later any remixing of light phase
liquid and heavy phase around stopper-piston 14. When
stopper-piston 14 is at its initial position, as in FIGS. 1 and 6,
rim portion 18 prevents stopper-piston 14 from sliding into
container 12 as tubular member 46 is inserted, even though
container 12 has been evacuated. In this connection, rim 18 rests
on the top edge surface of container 12 and helps prevent
stopper-piston 14 from sliding prematurely into container 12.
FIG. 4 illustrates a form of a closure cap 16 designed and employed
to maintain the top surface portion 15 of stopper-piston 14 in
aseptic condition prior to the filling of blood in collection
container 12. Cap 16 is made of a resilient material which is
capable of being penetrated by a pointed tubular member 34 as
illustrated in FIG. 6. During the blood collection step, cap 16 is
either removed or is not removed from the assembly as preferred. If
not removed, during this procedure, the pointed tubular member
pierces cap 16 and then stopper-piston 14, the force of the needle
penetration being insufficient added force to cause stopper-piston
14 to be pushed into container 12. After the blood is collected the
collection assembly is ready for processing.
FIG. 7 illustrates blood collection assembly 10 with stopper-piston
14 moved toward the blood cell and plasma interface by employing a
pusher element or member 30. Pusher 30 is elongated and has a shaft
31 and a finger engaging head portion 32 at its upper or outer end.
A pointed tubular member 34 is mounted at the lower or inner end of
shaft 31. The lower end of shaft 31 is formed having a
longitudinally extending slot 35 having a diameter sufficient to
mount tubular element 34 therein. Tubular element 34 is fitted into
a hub 33 and is rigidly mounted within slot 35. The pointed end 37
of tubular member 34 is capable of piercing stopper-piston 14. As
illustrated in FIG. 7, tubular member 34 has pierced stopperpiston
14 to form a passage therethrough so as to conduct plasma "P"
through stopper-piston 14 through its exit opening 38 at the other
end of tubular member 34 so that plasma "P" becomes separated from
the cellular portion "C" in container 12. After pusher member 30
has moved stopper-piston 14 to a location adjacent the blood
cell-plasma/serum interface 50, pusher 30 is removed and piston 14
seals itself and a permanent barrier is thereby formed between
cells "C" and plasma "P," as illlustrated in FIG. 8.
For a better understanding of practicing the invention herein
reference is had to FIGS. 6, 7 and 8. When a blood sample is to be
collected in the blood collection assembly of FIG. 1 a blood
collecting apparatus such as is disclosed in U.S. Pat. No.
2,460,641 may be employed.
As shown in FIG. 6, the apparatus includes a holder 40 open at one
end and closed at the other end. The closed end is formed having a
threaded passageway 42 for receiving a threaded hub 44 supporting
tubular member 46. The tubular member 46 is mounted in hub 44
intermediate its ends 47 and 48. Ends 47 and 48 are pointed and are
capable of piercing a vein "V" and stopper-piston 14 and cap 16 as
depicted in FIG. 6. After pointed end 48 has punctured vein "V,"
blood collection assembly 10 is pierced by pointed end 47 of
tubular member 46 so that a blood sample is sucked into evacuated
tube 12. After the blood sample is collected assembly 10 is removed
from holder 40 and is then processed for chemical testing in the
usual manner, such as by centrifuging to separate the serum or
plasma from the cellular phase.
Then pointed tubular member 34 mounted on pusher 30 is pushed
downwardly until it pierces stopper-piston 14. With tubular member
34 in position a passage from the lower side of stopper-piston 14
to the upper side is provided. Then by exerting downward pressure
on pusher 30 and by moving the stopperpiston 14 downwardly the
plasma or serum is conducted through the plasma or serum is
conducted through tubular element 34 and is stored on the upper
surface 15 of stopper-piston 14. When pointed end 37 of tubular
member 34 and the stopper-piston 14 approach the blood interface 50
the downward force is stopped and pusher 30 is pulled out of
stopper-piston 14 so that a permanent barrier is formed between the
plasma on one side of stopper-piston 14 and the cells on the other.
The plasma is then ready for testing in the usual manner.
In FIG. 8, blood collection assembly 10 is illustrated with
stopper-piston 14 adjacent the blood interface 50. Cap 16 is
mounted over the open end of blood collection container 12. The
blood collection assembly 10 can then be stored, transported or can
be used to obtain samples of plasma or serum to perform various
tests. Further, the blood collection assembly in the form
illustrated in FIG. 8 can be shipped for subsequent testing at a
different laboratory or facility.
It is apparent that the several objects of the invention as set
forth herebefore have been accomplished and it is obvious that
numerous changes in structures or the steps required for practicing
the invention can be employed without departing from the invention
as defined in the claims.
* * * * *