JP2598959Y2 - Blood separation tube - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blood separation tube containing a thixotropic gel-like separating agent used for centrifuging blood components using a specific gravity difference.

[0002]

2. Description of the Related Art A thixotropic gel-like separating agent, for example, silicone (see JP-A-51-83654), chlorinated polybutene (see JP-A-57-9718), or cyclopentadiene resin (see JP-A-51-9718). 295
163) and propylene glycol (see Japanese Patent Application Laid-Open No. 1-295163), such as silica, which acts as a specific gravity adjusting agent like silica and also acts as a gelling agent for imparting thixotropic properties. There is known a blood separation tube in which a composition containing an organic gelling agent such as dibenzylidene sorbitol (see Japanese Patent Application Laid-Open No. 2-168159) and a viscosity modifier is contained in the bottom of a blood collection tube.

[0003] Blood is collected in the blood separation tube, allowed to stand for an appropriate period of time, and then centrifuged. The centrifugal force causes this gel-like separating agent to become a fluid, and has a specific gravity intermediate between the serum component and the blood cell component. , It gradually rises from the bottom of the tube, comes to a position intermediate between the serum phase and the blood cell phase, and forms a partition, so that the serum phase and the blood cell phase can be separated.

[0004] When a thixotropic gel-like separating agent is stored in this blood separation tube, the separating agent is usually stored such that the upper surface thereof is flat.

[0005]

However, if the upper surface of the separating agent is flat, a large centrifugal force is required to start the flow of the separating agent at the time of centrifugation, and if the separating agent is separated by a large centrifugal force, hemolysis of red blood cells may occur. There has been a problem that accurate test values of biochemical components in blood cannot be obtained. Therefore, if the upper surface of the thixotropic gel-like separating agent 3 is inclined at a considerable angle in the bottomed blood collection tube 2 as in the blood separation tube 1 in FIG. Inclination at an angle requires centrifugation after injecting the separating agent into the blood collection tube, or requires complicated injection equipment, and this method is not economically favorable. As a proposal leading to the solution of these problems, as shown in FIG. 6, as shown in FIG. 6, blood separation stored in a bottomed blood collection tube 2 in a state where the central portion of a thixotropic gel-like separating agent 3 is convex upward. There is a tube 1 (JP-A-60-5)
No. 3845). However, even with this proposal,
The separability varied, and was not satisfactory.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a blood separation tube capable of separating blood with a small centrifugal force and easily manufactured.

[0007]

The blood separation tube of the present invention comprises:
A thixotropic gel-like separating agent having an intermediate specific gravity between the phases to be separated is housed in a bottomed blood collection tube in a convex shape upward, and the center of the convex portion is eccentric.

The thixotropic gel-like separating agent (hereinafter referred to as the separating agent) used in the present invention is not particularly limited as long as it has an intermediate specific gravity between the phases to be separated. The main component is silicone, chlorinated polybutene, cyclopentadiene resin, α-olefin-maleic acid diester copolymer, ester polymer or acrylic polymer, and at the same time acts as a specific gravity adjuster like silica. Examples of the composition include a composition in which an inorganic filler which also functions as a gelling agent for imparting thixotropic properties, an organic gelling agent such as propylene glycol and dibenzylidene sorbitol, and a viscosity modifier are blended. The specific gravity is about 1.02 to 1.08 in the case of separating blood serum or plasma from blood clots or blood cells.

The material of the bottomed blood collection tube used in the present invention is as follows.
Any conventionally used material such as synthetic resin and glass can be used. As the synthetic resin, for example, polyethylene terephthalate, polycarbonate, polystyrene, polypropylene, polyethylene and the like are preferable because they are inexpensive and easy to mold.

The present invention will be described below with reference to the drawings.
FIG. 1 shows a blood separation tube 1 of the present invention, which comprises a tubular bottomed blood collection tube 2 having one end closed and the other end opened, and a thixotropic gel-like separating agent 3 housed in the tube 2. Become.

The thixotropic gel-like separating agent 3 is accommodated in the tube 2 so as to protrude upward, and the center 3b of the protruding portion 3a is eccentric.

Next, the size of the convex portion 3a will be described. In the vertical cross-sectional view of the main part of the blood separation tube shown in FIG. 2, of the two intersections between the skirt of the convex portion and the wall surface of the blood collection tube,
The intersection of the upper part is A, the intersection of the lower part is B, the intersection of the straight line passing through the upper intersection A and perpendicular to the pipe axis and the hem of the convex part is C,
Let D be the vertex of the convex portion, and let E be the intersection of a perpendicular line A-C drawn from the vertex D to a line A-C. A and C above
Is defined as the width of the bottom surface of the convex portion 3a, the width of the bottom surface is limited to 10 to 80% of the inner diameter of the bottomed blood collection tube 2.
Outside this range, small centrifugal forces make it difficult to separate blood. The distance between D and E is set to the convex portion 3
When defined as the height of a, the height is limited to 10% or more of the average thickness of the separating agent. Outside this range, small centrifugal forces make it difficult to separate blood. In addition,
The average thickness of the separating agent, using the same amount of the separating agent,
It refers to the distance from the bottom of the tube to the surface of the separating agent when it is injected into the tube 2 so that the surface becomes flat without forming a convex portion.

The degree of the eccentricity of the center 3b of the convex portion 3a is set to be within a range of from 20 to the radius of the
Only 60% that is eccentric. When the ratio of the polarized heart decreases, becomes difficult to perform a little separation of the blood in the small centrifugal force, larger and or easily separating agent adheres to the tube wall of the blood collection tube, it is hardly performed slightly to separate the blood in small centrifugal force .

As an example of the method for manufacturing the blood separation tube 1 of the present invention, as shown in FIG.
And the tip 4a of the nozzle 4 of the pipetting machine (not shown) to the pipe 2
Is set at a position eccentric by 20 to 60% of the radius of the pipe 2 from the center of the pipe 2 in the circumferential direction. When the injection is completed, the separating agent 3 is slowly pulled up while the separating agent 3 is accompanied by the nozzle 4 and cut. By performing such an operation, the center 3b of the convex portion 3a of the separating agent 3 can be decentered. Since the injected separating agent 3 has thixotropy, it keeps its shape until it is centrifuged.

[0015]

In the blood separation tube of the present invention, the center of the protruding portion of the separating agent accommodated in the bottomed blood collection tube is a center of the tube.
From 20 to 60% of the radius of the tube in the circumferential direction of the tube, and the width of the bottom surface of the protrusion and the height of the protrusion are
Since it is limited as described above, as shown in FIG.
When the collected blood coagulates and separates into the serum phase 5a and the blood cell phase 5b, the separating agent contact surface of the coagulated blood cell phase 5b is also formed along the upper surface shape of the separating agent. Since the centrifugal separation is performed in such a state, since the left and right shapes of the separating agent and the blood cell phase are asymmetric, a large centrifugal force is not required to start the flow of the separating agent.

[0016]

Embodiments of the present invention will be described below. (Example 1) Manufacture of blood separation tube A cylindrical blood collection tube (made of polyethylene terephthalate) having an inner diameter of 10.7 mm at the mouth, an outer diameter of 13.3 mm, an inner diameter of the bottom of 9.5 mm, an outer diameter of 12.2 mm, and a length of 100 mm. ), Cyclopentadiene resin (trade name “ECR-327” manufactured by Exxon Chemical Co., Ltd.), di (2-ethylhexyl) phthalate, dibenzylidene sorbitol (trade name “Gerol D” manufactured by Nippon Rika Co., Ltd.) ) And silica (trade name "Aerosil", manufactured by Nippon Aerosil Co., Ltd., average primary particle size: about 7 n)
m) is mixed with a thixotropic gel-like separating agent (specific gravity: 1.05, viscosity: 150,000 cp, 25 ° C.) with the tip of the nozzle of the dispenser in the circumferential direction of the pipe from the center of the pipe to a radius of 20 mm. %
0.9 ml was injected eccentrically by (1 mm), and when the injection was completed, the nozzle was accompanied by a separating agent and slowly pulled up to cut the separating agent. As a result, the center of the convex portion of the separating agent was eccentric from the center of the blood collection tube by 20% of the radius of the tube. The width (7 mm) of the bottom surface of the formed convex portion is the inner diameter of the pipe (10 mm).
mm). In addition, the height of the convex portion (4 m
m) was about 27% of the average thickness (15 mm) of the separating agent. A blood separation tube was manufactured as described above.

Performance test Using the above 50 blood separation tubes, each tube had a specific gravity of 1.08.
Of saline solution, and centrifugal force of 800 G and 1000
Centrifuged at 15 ° C. for 5 minutes at G. Separately, using the 50 blood separation tubes described above, a silica-based coagulation promoter was applied to each tube, 5 ml of fresh human blood was collected, left at 23 ° C. for 1 hour to confirm blood coagulation, and then centrifuged. Centrifuged at a temperature of 15 ° C. for 5 minutes at a force of 800 G and 1000 G. After centrifugation, the moving state of the thixotropic gel-like separating agent in each blood separation tube was observed, and the thickness of the formed separating agent partition was measured and evaluated as follows. ：: Separating agent partition wall thickness of 5 mm or more Δ: Separating agent partition wall thickness of 2 to 5 mm ×: Separating agent partition wall thickness of 0 mm That is,
The separation agent did not move by centrifugation. Percentage of blood separation tubes classified as above for evaluation (%)
And the results are shown in Table 1.

Example 2 In Example 1, the thixotropic gel-like separating agent was injected with the tip of the nozzle of the dispenser eccentric from the center of the tube by 20% of the radius of the tube in the circumferential direction of the tube. Instead, a blood separation tube was manufactured in the same manner as in Example 1 except that the injection was performed with the tip of the nozzle of the dispenser eccentrically injected from the center of the tube in the circumferential direction of the tube by 40% (2 mm) of the radius of the tube. . As a result, the center of the convex portion of the separating agent is positioned at a radius of 40 mm from the center of the blood collection tube.
Was eccentric by only%. The width of the bottom surface of the formed convex portion (6
mm) was 60% of the inner diameter of the tube (10 mm). The height (3 mm) of the convex portion is determined by the average thickness of the separating agent (15 mm).
mm). A blood separation tube was manufactured as described above. Using the obtained blood separation tube, a performance test was conducted using saline and fresh human blood in the same manner as in Example 1, and the results are shown in Table 1.

Comparative Example 1 The procedure of Example 1 was repeated except that the thixotropic gel-like separating agent of Example 1 was injected into the blood collection tube of Example 1 so that the upper surface of the separating agent became flat. To produce a blood separation tube. Using the blood separation tube thus obtained, a performance test was performed using saline and fresh human blood in the same manner as in Example 1, and the results are shown in Table 1.

(Comparative Example 2) Instead of injecting the thixotropic gel-like separating agent in Example 1 with the tip of the nozzle of the dispenser being eccentric by 20% of the radius of the pipe from the center of the pipe to the circumference of the pipe, Then, a blood separation tube was manufactured in the same manner as in Example 1 except that the tip of the nozzle of the dispenser was injected without being eccentric with the center of the tube. As a result, the center of the convex portion of the separating agent coincided with the center of the blood collection tube. The width of the bottom of the formed convex portion (about 1
0 mm) was almost 100% of the inner diameter of the tube (10 mm). Further, the height (5 mm) of the convex portion was about 33% of the average thickness (15 mm) of the separating agent. As described above,
A blood separation tube was manufactured. Using the obtained blood separation tube, a performance test was conducted using saline and fresh human blood in the same manner as in Example 1, and the results are shown in Table 1.

(Comparative Example 3) The blood separation tube obtained in Comparative Example 1 and into which the separating agent was injected flat was inclined obliquely and centrifuged, and the upper surface of the separating agent was inclined obliquely as shown in FIG. . The inclination angle was about 56 degrees. Using the obtained blood separation tube, a performance test was performed using saline and fresh human blood in the same manner as in Example 1, and the results were shown in Table 1.
It was shown to.

(Comparative Example 4) The blood separation tube obtained in Comparative Example 1 into which the separating agent was flatly injected was inclined obliquely and centrifuged, and the upper surface of the separating agent was inclined obliquely as shown in FIG. . The inclination angle was about 17 degrees. Using the obtained blood separation tube, a performance test was performed using saline and human fresh blood in the same manner as in Example 1. As a result, almost the same results as those obtained in Comparative Example 1 were obtained. Was done.

[0023]

[Table 1]

The eccentricity shown in the column of the shape of the convex portion in Table 1 is the ratio of the distance between the center of the convex portion and the center of the blood collection tube to the radius of the blood collection tube. The width of the bottom is the ratio of the width of the bottom of the convex portion to the inner diameter of the blood collection tube, and the height is the ratio of the height of the convex portion to the average thickness of the separating agent.

[0025]

The structure of the blood separation tube of the present invention is as described above, and the thixotropic gel-like separating agent is accommodated in a bottomed blood collection tube in a convex upward shape, and the center of the convex portion is the tube. of
Eccentric by 20 to 60% of the radius of the pipe from the center to the circumference of the pipe
As well as the width of the bottom of the projection and the height of the projection.
As described above , the separation agent does not require a large centrifugal force to start the flow of the separating agent. Therefore, since blood can be separated with a small centrifugal force, it is possible to prevent adverse effects on test values due to damage of blood cell components. In addition, since the partition walls formed by the separating agent after centrifugation can be made thicker, it is possible to prevent adverse effects on test values due to bleeding of the blood cell phase. Furthermore, since the eccentric operation can be easily performed by adjusting the blood collection tube holding table without moving the nozzle, the manufacturing is simple.

[Brief description of the drawings]

FIG. 1 is a partially cutaway longitudinal sectional view showing an example of a blood separation tube of the present invention.

FIG. 2 is a longitudinal sectional view of a main part showing a shape of a convex portion of the blood separation tube.

FIG. 3 is a vertical sectional view of a main part showing a step of injecting a separating agent.

FIG. 4 is a longitudinal sectional view of a main part showing a coagulation state of blood.

FIG. 5 is a partially cutaway longitudinal sectional view showing a conventional blood separation tube.

[FIG. 6] FIG. 6 is a longitudinal sectional view of a main part showing a conventional blood separation tube.

[Explanation of symbols]

 Reference Signs List 1 blood separation tube 2 bottomed blood collection tube 3 thixotropic gel separating agent 3a convex portion 3b center of convex portion 4 nozzle 4a tip of nozzle 5a serum phase 5b blood cell phase

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G01N 33/48-33/52 G01N 33/58-33/98

Claims (1)

(57) [Scope of request for utility model registration] 1. A blood separation tube comprising a bottomed blood collection tube and a thixotropic gel-like separating agent accommodated at the bottom of the blood collection tube and having an intermediate specific gravity between phases to be separated. separating agent is contained in the tube convex upward, and the center of the convex portion is eccentric, in a longitudinal sectional view of the blood separation tube, and the skirt of the convex portion bled
Of the two intersections with the wall of the pipe, the upper intersection is A, the lower one
Is a line perpendicular to the pipe axis passing through the upper intersection A
Is the intersection of C with the bottom of the convex part, and D is the vertex of the convex part.
And a straight line A-C of a perpendicular line lowered from the vertex D to a straight line A-C
When the intersection with E is E, the width of the bottom surface of the convex portion defined as the distance between A and C is
10 to 80% of the inner diameter of the bottomed blood collection tube, and the height of the convex portion defined as the distance between D and E is
It is 10% or more of the average thickness of the release agent, and the degree of eccentricity of the center of the convex portion is from the center of the pipe to the pipe circumference.
Direction is eccentric by 20 to 60% of the radius of the tube
A blood separation tube characterized by the following.