JPH11295298A - Blood filtering unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the simple filtering of test blood anywhere and to obtain blood serum and blood plasma by sealing a nozzle to suck blood and a filtrate outlet in such a way that they can be opened, bringing the inside to a depressurized state, and housing in a blood sampling container. SOLUTION: A blood filtering unit provided with a blood filtering material such as glass fiber filter paper, a polysulfone porous film is, for example, placed to a vacuum blood sampling tube 60 by fitting the tip opening of a suction nozzle 50 into a plug 61 provided at the bottom surface of the blood sampling tube 60. After the blood sampling tube 60 is depressurized, sealing material sheets 62 and 63 are each adhered to the opening part of the blood sampling tube 60 and its upper end opening part, which is the filtrate outlet of the blood filtering unit. Then a sampled blood specimen is taken into the blood sampling tube 60, and the plug 61 is removed at the time when the tip opening of the nozzle 50 is entered in the blood. The blood is sucked from the nozzle 50, is passed through the blood filtering material, is, for example, entered in a filtrate storage provided in the blood filtering unit, and is sampled for analysis by sticking the sheet 63 with an analyzer sampling nozzle, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blood filtration unit used for preparing a plasma or serum sample from whole blood, and to a plasma or serum collection device using the same.

[0002]

2. Description of the Related Art The type and concentration of constituents in blood such as metabolites, proteins, lipids, electrolytes, enzymes, antigens and antibodies are usually measured using plasma or serum obtained by centrifuging whole blood. Have been done. However, centrifugation takes time and effort. In particular, when a small number of samples are to be processed quickly or on site, the centrifugal method using electricity and requiring a centrifuge is not suitable. Thus, methods for separating plasma and serum from whole blood by filtration have been studied.

[0003] For this filtration method, several methods have been known in which a column is filled with glass fiber filter paper, whole blood is injected from one side of the column, and pressure or pressure is reduced to obtain plasma or serum from the other side. (Japanese Patent Publication No. 44-14673,
JP-A-2-208565, JP-A-4-20885
No. 6, Japanese Patent Publication No. 5-52463, etc.).

[0004] However, the method of obtaining the amount of plasma or serum necessary for measurement by automatic analysis or the like from whole blood by filtration is still in the trial stage except for some items such as blood sugar, and has been widely put into practical use. Has not been reached.

Therefore, the present inventors have previously developed a blood filtration unit capable of efficiently separating plasma and serum even with a small amount of blood by combining glass fiber filter paper with a microporous membrane as a filter medium, A blood filtration unit in which the opening area of the filtration material was narrowed by providing a seal member on the outlet side was completed (Japanese Patent Application Laid-Open No. 9-196911).

[0006] Further, a device provided with a plasma receiving tank on the suction side has already been developed (Japanese Patent Application Laid-Open No. 9-276631).

[0007]

However, these blood filtration units have a problem in usability. That is, the collected blood is transferred into a blood collection tube or the like, and the blood collection tube is removed and the suction nozzle of the blood filtration unit is inserted into the blood collection tube when analyzing the blood. However, this method places a burden on workers in a laboratory that analyzes a large number of blood samples. Further, since a suction / filtration of blood requires a decompression device, blood filtration cannot be performed anywhere, and the place where filtration can be performed is limited.

[0008] It is an object of the present invention to provide a blood filtration unit and a plasma or serum collection tool that can easily filter blood to be tested anywhere to obtain a required amount of plasma or serum.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide a blood filtration unit containing a blood filtration material, provided with a nozzle for sucking blood and a filtrate outlet, wherein the opening of the nozzle and the filtrate outlet are both provided. Is also openably sealed,
The problem is solved by a blood filtration unit whose inside is in a decompressed state, and a plasma or serum collecting tool housed in a container for storing blood collected by the blood filtration unit.

[0010]

Although the type of blood filtration material is not limited, the filtration material of the present invention is not a so-called surface filtration material that traps blood cells only on its surface, but penetrates in the thickness direction of glass fiber filter paper or the like. Accordingly, a so-called volume filtration material is used in which a large blood cell component is initially entangled with a small blood cell component, and the blood cell is gradually retained and removed over the entire length in the thickness direction. Preferred are glass fiber filtration, microporous membranes and the like, and a combination of glass fiber filter paper and microporous membrane is particularly preferred.

The glass fiber filter paper has a density of 0.05 to 0.5.
Degree, preferably about 0.07 to 0.35, particularly preferably about 0.09 to 0.2, and the retained particle diameter is 0.8 to 9 μm.
m, particularly preferably about 1 to 5 μm. The surface of the glass fiber is described in JP-A-2-208565,
By treating with a hydrophilic polymer by the method described in JP-A-208856, filtration can be performed more quickly and smoothly. Further, the surface of the glass fiber can be treated with lectin. The glass fiber filter paper can be used by laminating a plurality of sheets.

A microporous membrane having a hydrophilic surface and capable of separating blood cells, specifically separates blood cells and plasma from whole blood without substantially hemolyzing so as to substantially affect analytical values. Things. This microporous membrane has a pore size smaller than the retained particle size of the glass fiber filter paper and 0.2 μm or more, preferably about 0.3 to 5 μm, more preferably 0.5 to 3 μm.
m is appropriate. Further, the porosity is preferably high, and specifically, the porosity is about 40% to about 95%.
%, Preferably from about 50% to about 95%, more preferably from about 70% to about 95%. Examples of the microporous membrane include a polysulfone membrane and a fluorine-containing polymer membrane.

As a microporous membrane of a fluorine-containing polymer,
JP-T-63-501594 (WO 87/022)
67) a microporous matrix membrane (microporous layer) comprising polytetrafluoroethylene fibrils (fine fibers) described in Gole-Tex (WL Gore an;
d Associates), Zitex (Nor
ton) and Poreflon (manufactured by Sumitomo Electric). In addition, microporous polytetrafluoroethylene membranes described in US Pat. No. 3,268,872 (Examples 3 and 4), US Pat. No. 3,260,413 (Examples 3 and 4), and JP-A-53-92195 (US Pat.
And microporous membranes of polyvinylidene fluoride described in US Pat.

The microporous membrane of the fluorine-containing polymer has a low surface tension as it is, and even if it is used as a blood cell filtration layer of a dry analytical element, the aqueous liquid sample is repelled and diffuses on the surface or inside of the membrane. It is a well-known fact that it does not penetrate. In the present invention, as a first means for imparting hydrophilicity to the fluorine-containing polymer microporous membrane and increasing the hydrophilicity, the outer surface and the inner void surface of the fluorine-containing polymer microporous membrane are substantially treated. The above problem of repelling the aqueous liquid sample was solved by impregnating the microporous membrane of the fluorine-containing polymer with a surfactant in an amount sufficient to make it hydrophilic.

Surfactants used for hydrophilizing a fluorine-containing polymer microporous membrane include nonionic (nonionic), anionic (anionic), cationic (cationic), and amphoteric. Any surfactant can be used.

Among these surfactants, nonionic surfactants have a relatively low effect of lysing erythrocytes, and are therefore advantageous in a multi-layer analytical element for using whole blood as a sample. Examples of the nonionic surfactant include alkylphenoxypolyethoxyethanol, alkylpolyether alcohol, polyethylene glycol monoester, polyethylene glycol diester, higher alcohol ethylene oxide adduct (condensate), polyhydric alcohol ester ethylene oxide adduct (condensate), And higher fatty acid alkanolamides.

The fluorine-containing polymer microporous membrane may be made hydrophilic by providing one or more water-insoluble water-soluble polymers in the porous space. As examples of water-soluble polymers, hydrocarbons containing oxygen include polyvinyl alcohol, polyethylene oxide, polyethylene glycol, methylcellulose, ethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, and those containing nitrogen include polyacrylamide, polyvinylpyrrolidone, and polyvinylamine. Polyethyleneimine and polyacrylic acid, polymethacrylic acid, polystyrenesulfonic acid, and the like having a negative charge can be given. The insolubilization may be performed by heat treatment, acetalization treatment, esterification treatment, chemical reaction with potassium dichromate, crosslinking reaction with ionizing radiation, or the like. For details, see JP-B-56-2094 and JP-B-5-2094.
It is disclosed in JP-A-6-16187.

The polysulfone microporous membrane is prepared by dissolving polysulfone in dioxane, tetrahydrofuran, dimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone or a mixed solvent thereof to prepare a membrane-forming stock solution. It can be produced by casting on a body or directly in a coagulating liquid, washing and drying. Details are disclosed in JP-A-62-27006. Polysulfone microporous membranes are also disclosed in
JP-A-6-12640, JP-A-56-86941, JP-A-56-154051 and the like are also disclosed, and these can also be used. The microporous membrane of polysulfone can be made hydrophilic by containing a surfactant similarly to the fluorine-containing polymer, or by providing a water-insoluble water-soluble polymer.

Other non-fiber microporous membranes include cellulose esters described in JP-B-53-21677 and US Pat. No. 1,421,341, such as cellulose acetate, cellulose acetate / butyrate, and cellulose nitrate. Is preferred. Polyamides such as 6-nylon and 6,6-nylon,
A microporous membrane such as polyethylene and polypropylene may be used. In addition, Japanese Patent Publication No. 53-21677,
For example, a porous membrane having continuous voids in which small polymer particles, glass particles, diatomaceous earth, and the like described in JP-A-90859 and the like are bonded by a hydrophilic or non-water-absorbing polymer can also be used.

The effective pore size of the non-fibrous microporous membrane is 0.2 to 1
0 μm, preferably 0.3 to 5 μm, particularly effective is 0.5 to 3 μm. In the present invention, the effective pore size of the non-fibrous microporous membrane is represented by the pore size measured by the critical bubble pressure method (bubble point method) according to ASTM F316-70.
When the non-fibrous microporous membrane is a membrane filter made of a so-called brush polymer made by a phase separation method, the liquid passage in the thickness direction is on the free surface side (that is, the glossy surface) in the production of the membrane. Usually the narrowest, the hole diameter when the cross section of the liquid passage path is approximated to a circle,
It is smallest near the free surface. The minimum pore size in the thickness direction in the passage path of the volume further has a distribution in the plane direction of the filter, and the maximum value determines the filtering performance for the particles. Usually, it is measured by the limiting bubble pressure method.

As mentioned above, in a membrane filter made of a so-called brush polymer made by a phase separation method, the liquid passage in the thickness direction is on the free surface side (that is, the glossy surface) in the production of the membrane. The narrowest. When this type of membrane is used as the non-fiber microporous membrane of the analytical element of the present invention, it is preferable that the outlet side be a glossy surface of the membrane filter.

A third filtration material can be added to the blood filtration material used in the present invention in addition to the glass fiber filter paper and the microporous membrane. Examples of the third filtering material include a fibrous porous layer such as filter paper, nonwoven fabric, woven fabric (for example, plain woven fabric), and knitted fabric (for example, tricot knit). Of these, woven fabrics and knitted fabrics are preferred. The fabric may be subjected to a glow discharge treatment as described in JP-A-57-66359. This third filter material is preferably located between the glass fiber filter paper and the microporous membrane.

Preferred microporous membranes are polysulfone membranes and cellulose acetate membranes, and particularly preferred are polysulfone membranes. In the blood filtration material of the present invention, the glass fiber filter is disposed on the blood supply side, and the microporous membrane is disposed on the suction side. The most preferable material is a laminate in which glass fiber filter paper and a polysulfone membrane are laminated in this order from the blood supply side.

The filtration material used in the present invention is disclosed in
According to the methods disclosed in JP-A-138756-8, JP-A-2-105043, JP-A-3-16651, etc., each layer can be integrated by bonding with a partially disposed adhesive.

The amount of whole blood that can be filtered by this method is greatly affected by the volume of space present in the glass fiber filter paper and the volume of blood cells in whole blood. If the density of the glass fiber filter paper is high (the particle retention hole diameter is small), red blood cells are trapped near the surface of the glass fiber filter paper, and the space in the glass fiber filter paper may become blocked in a very shallow area from the surface. Many. Therefore, further filtration does not proceed, and as a result, the amount of serum that can be filtered and collected also decreases. At this time, if the pressure is increased under stronger conditions in order to increase the amount of collected serum, the blood cells are destroyed, that is, hemolysis occurs. In other words, the process becomes similar to surface filtration, and the space volume utilization efficiency of the filter paper is low.

On the other hand, when the density of the glass fiber filter paper is reduced, blood cells permeate deep into the filter paper (the area near the outlet) and the space through which serum can pass is increased, so that the entire volume of the filter paper is effectively used. As a result, the amount of serum collected increases.

The water permeation rate is effective as an index corresponding to the space volume or the amount of serum filtration. The water permeation rate is the unit when a glass fiber filter paper of a certain area is hermetically sealed in a filtration unit squeezed so that the inlet and outlet can be connected to a tube, and a certain amount of water is added and pressurized or depressurized at a certain pressure. The amount of filtration per area is expressed in terms of speed.
It has units such as sec.

As a specific example, a filter having a diameter of 2
Set a 0mm glass fiber filter paper and put 100m on it
1 ml of syringe is set up and 60 ml of water is poured and allowed to flow naturally. The amount of water that has passed through the glass filter paper for 30 seconds between 10 seconds and 40 seconds after the start is defined as the amount of water permeation. Calculate the permeability rate.

Particularly suitable for serum filtration are those having a water permeation rate of about 1.0 to 1.3 ml / sec.
Whatman GF / D, Toyo filter paper GA-100, GA
-200 and the like. In addition, commercially available glass fiber filter paper can be redispersed in hot water and re-papered on a nylon net to produce a low density filter paper (density about 0.03), which shows good plasma filtration properties. .

The thickness of the glass fiber filter paper is determined from the amount of serum to be collected and the density (porosity) and area of the glass fiber filter paper. When performing a plurality of analysis using a dry analytical element, the required amount of plasma is 100 to 500 μl, the density of the glass fiber filter paper is about 0.07 to 0.2, and the area is 1 to 5 μm.
About ² cm ² is practical. In this case, the thickness of the glass fiber filter paper is about 1 to 10 mm, preferably about 2 to 8 mm. This glass fiber filter paper can be laminated to a plurality of sheets, for example, about 2 to 10 sheets, preferably about 2 to 6 sheets, to have the above thickness.

The thickness of the microporous membrane is 0.05 to 0.5 mm
The thickness may be about 0.1 to 0.3 mm, and usually one microporous membrane may be used. However, a plurality of sheets can be used if necessary.

The blood filtration material is placed in a holder. This holder is provided with a blood inlet and a filtrate outlet, and is generally manufactured in a mode in which a main body containing a blood filtering material and a lid are separated. Usually, each has at least one opening, one used as a blood inlet, the other as a filtrate outlet, and optionally also as a suction port. A suction port may be separately provided. When the holder is square and the lid is provided on the side, both the blood inlet and the filtrate outlet can be provided on the main body.

It is necessary that the volume of the blood filtering material storage section is larger than the total volume of the filter material to be stored in a dry state and when a sample (whole blood) is absorbed and swollen. If the volume of the storage part is small with respect to the total volume of the filtration material, filtration does not proceed efficiently or hemolysis occurs. Although the ratio of the volume of the storage portion to the total volume of the filter material when dried is dependent on the degree of swelling of the filter material, it is usually 101% to 400%, preferably 110% to 150%, and more preferably 120% to 1%.
40%. Specifically, it is determined depending on the required amount of plasma or serum, but is about 0.5 to 2.5 ml, usually 0.6 to 2.
It is about 2 ml.

In addition, between the filtering material and the wall surface of the storage section,
It is needless to say that it is necessary to configure such that a flow path that does not pass through the filtration material is not formed when whole blood is sucked.
However, there is no problem even if blood cells leak to such an extent that they can be stopped by the microporous membrane.

The blood suction nozzle is connected to the blood inlet of the holder. This nozzle may be the same as or separate from the holder. In the case of a separate body, it is sufficient that the connection part is fixed to the holder body so as to have a sealed structure, and the connection means may be any means such as adhesion, fusion, screwing, fitting, screwing, and the like.

When the lid is attached to the main body, the filtration unit has a hermetically sealed structure except for the blood inlet and the filtrate outlet which is also used as a suction port.

The material of the holder is preferably plastic. For example, a transparent or opaque resin such as polymethacrylate, polyethylene, polypropylene, polyester, nylon, and polycarbonate is used.

The main body and the lid may be attached by any means such as joining using an adhesive and fusion. In this case, the peripheral edge of either the main body or the lid may be located inside, or may be in an abutting state. Also,
The main body and the lid may be structured so that they can be assembled and disassembled by means such as screws.

Although there is no particular limitation on the shape of the blood filtration material,
A circular shape is desirable for ease of manufacture. At this time, the diameter of the circle is made slightly larger than the inner diameter of the holder main body, so that the plasma can be prevented from leaking from the side surface of the filtration material. On the other hand, it is preferable to use a square shape, since cutting loss of the produced blood filtration material is eliminated. Also, a strip of glass fiber filter paper can be used.

The present invention is characterized in that the opening of the blood suction nozzle and the filtrate outlet of such a blood filtration unit are openably sealed and the inside thereof is in a reduced pressure state. Here, "sealing" means that the inside of the holder accommodating the blood filtration material is in an airtight state by cutting off the flow of air from the outside world, and "opening" can break this airtight state and circulate with the outside world. It refers to the state.

The outlet of the filtrate is sealed by attaching a cap to the outlet, attaching a sheet or film, or the like. The cap may be attached by screwing, fitting, bonding, fusion, etc., and the sheet or film may be attached by adhesion, fusion, etc. Sealing materials such as caps, stoppers, sheets, films, etc. that can block air for a long period of time are good.For caps, polyvinylidene chloride, polypropylene, high-density polyethylene, polyethylene terephthalate, nylon, a composite of thermoplastic film and aluminum foil laminated For films, stoppers for various rubbers, for sheets, polyvinylidene chloride, polypropylene,
It is preferable to use a high-density polyethylene or the like, particularly a laminate of a metal foil such as aluminum or a deposited film. In the case of a sheet or a film, those having a thickness of about 0.01 to 0.2 mm, preferably about 0.07 to 0.15 mm are suitable. However, when the whole blood filtration unit is housed in a sealed container under reduced pressure and supplied to the user, the airtightness of the sealing material may be such that the airtightness can be secured, for example, for 10 minutes. When the plasma or serum obtained by filtration is analyzed, it is preferable that the sealing material be broken by piercing a needle or a thin rod, preferably by descending a sampling nozzle of an analyzer.

When the suction port is provided separately from the filtrate outlet, it goes without saying that both the ports are sealed.

It is necessary to seal the nozzle for sucking blood so that the nozzle is opened after the opening of the nozzle enters the blood. For example, when a cap or plug is attached to the opening of the nozzle and sealed, a thread or the like is attached to the cap or plug, and after the opening enters the blood, the thread is pulled so that the cap or plug can be removed. Or a container that holds blood with a cap or plug fixed to the container that holds the blood so that the container can be removed by moving the container in the direction that the cap or plug is attached or detached. There is a protrusion at the bottom of the
There is a method such as smashing with a projection. These materials can be selected from the above-mentioned sealing materials at the filtrate outlet and used. In addition, caps and stoppers are made of magnetic materials,
In particular, it can be made of a ferromagnetic material so that it can be removed with a magnet, or it can be made of a heat-softening material, for example, a wax, and can be removed by heating.

When the nozzle for sucking blood is opened, the part to be decompressed needs to have at least a range in which the blood can be sucked, the blood filtering material can be passed, and the blood can be put into the filtrate reservoir in the blood filtering unit. . Specifically, this is a space connected from the blood suction nozzle to the filtrate reservoir via the blood filtration material storage section. The degree of decompression is such that at least a required amount of blood can be filtered, and specifically, -300 to -70.
About 0 mmHg, particularly about -500 to -650 mmHg, is appropriate, but the configuration of the blood filtration unit is different.
It can be determined experimentally.

It is preferable that the blood filtration unit of the present invention is housed in a container for storing collected blood in advance. For this container, for example, a commercially available blood collection tube can be used. This container is protected from the outside world by attaching caps and stoppers or attaching sheets or films. The container can be hermetically sealed with a cap, stopper, sheet, film or the like, and the inside can be kept under reduced pressure. In this case, the opening of the blood suction unit's blood suction nozzle may be left open, and the collected blood may be injected into the container by piercing a sheet, film, or stopper with the needle of the blood collector. it can.

[0046]

EXAMPLE 1 A blood filtration unit shown in FIGS. FIG. 1 is a longitudinal sectional view of a state where the blood filtration unit is assembled, FIG. 2 is a plan view of a lid constituting the blood filtration unit, and FIG. 3 is a bottom view of a lid constituting the blood filtration unit.

As shown in FIG. 1, the blood filtration unit has a holder 1, which comprises a holder body 10 and a lid 20 tightly fixed to the upper part thereof.

The holder body 10 is formed of a high-impact polystyrene resin. The holder body 10 has a glass fiber filter paper storage chamber 11 for storing a glass fiber filter paper 30 constituting a blood filtration material. Above the upper part 11, a microporous membrane storage chamber 12 for storing a polysulfone porous membrane 40 as a microporous membrane constituting a blood filtration material is formed. The microporous membrane storage chamber 12 has a glass fiber filter paper storage chamber 11 at the lower end.
A step 19 having a larger diameter is formed.
9, the polysulfone porous membrane 40 is accommodated in a mounted state. Further, an inclined portion 13 that rises obliquely upward from the outer peripheral edge of the step portion 19 is formed.
A flange 14 is formed outwardly from the upper edge of 3.

On the other hand, at the bottom of the holder body 10, a glass fiber filter paper mounting portion 15 is provided slightly inside from the peripheral edge, from which a shallow funnel-shaped disc portion 16 is connected. A nozzle-like blood inlet 17 extends downward from the nozzle. A suction nozzle (not shown) is attached to the nozzle-shaped blood inlet 17 during blood filtration. The glass fiber filter paper mounting portion 15 also functions as a spacer that forms a space 18 by separating the lower surface of the glass fiber filter paper 30 from the funnel-shaped disk portion 16 of the holder body 10.

The lid 20 has, from the outside, a concentric cylindrical outer wall 21, an inner wall 22, and a cup 23 for storing the filtered plasma. The outer wall 21
Is formed in a tapered shape that spreads outward as going upwards. The inclination angle of the outer wall 21 is the same as the inclination angle of the inclined portion 13, and the outer diameter is the same as the inner diameter of the inclined portion 13. ing. That is, the outer wall 21 is fitted to the inclined portion 13 in a close contact state. In addition, the outer wall 21
A flange 24 protruding outward is formed on the periphery of the
The flange 24 is ultrasonically bonded to the flange 14 of the holder body 10. As shown in FIG. 3, on the bottom surface of the flange 24 (surface to be bonded to the flange 14), at the stage before bonding, ultrasonic energy is collected there during bonding to ensure sufficient liquid tightness. Ribs 25 are formed so that they can be bonded (they are melted and disappeared after bonding).

As shown in FIG. 3, twelve projections 26 are formed on the bottom surface of the lid 20 at substantially equal intervals, and the projections 26 allow the polysulfone porous membrane 40 to adhere closely. Has been prevented.

Between the inner wall 22 of the lid 20 and the cup 23, a chimney-shaped plasma passage 27 is provided so as to penetrate through the lid 20 and project upward. Is formed in the horizontal direction. As shown in FIG. 2, the eave 28 has a shape in which two large and small semicircles are combined, and the inner semicircle is
7 coincides with the outer wall. Further, an inflow portion 29 that is inclined toward the cup 23 is formed in the upper end inside portion of the plasma passage 27 so that the filtered plasma 27 can easily flow into the cup 23.

In the above blood filtration unit, the diameter of the glass fiber filter paper storage chamber 11 is 20.1 m.
m, depth 5.9 mm, diameter 23.0 mm at the lower end of the microporous membrane storage chamber 12, diameter 22.5 at the upper end
mm, depth 2.10 mm, diameter of lower end of outer peripheral surface of outer wall 21 is 20.98 mm, height from lower surface to flange 24 is 2 mm, inner diameter of inner wall 22 is 15.0 mm, inner diameter of cup 23 is 7.5 mm, glass fiber Filter paper 30 diameter 20.0m
m, 6 sheets each having the same thickness of 0.91 mm, the diameter of the polysulfone porous membrane 40 being 20.9 mm, and the same thickness being 150 μm.

This blood filtration unit is used by mounting a suction nozzle 50 as shown in FIGS. The suction nozzle 50 is formed of a tapered thin tube, and a base end fitted into the blood inlet 17 has a large diameter portion 51 with a step. This suction nozzle 50 is made of polypropylene resin.

This blood filtration unit is placed in a vacuum blood collection tube 60 as shown in FIG. The vacuum blood collection tube 60 is made of polyethylene terephthalate, and a stopper 61 made of polyethylene terephthalate is fitted on the bottom surface of the suction nozzle 50 to be fitted and sealed.

The distal end opening of the suction nozzle 50 is fitted into the stopper 61, and the interior of the vacuum blood collection tube 60 is suctioned to reduce the pressure.
And the two are hermetically sealed. The sheets 62 and 63 are made of a thin aluminum / polyester composite having a thickness of 0.12 mm. The attachment is performed by thermocompression bonding. The sheet 62 for sealing the vacuum blood collection tube 60 is provided with a pull tab 64 used for peeling. The pressures in the vacuum blood collection tube 60 and the blood filtration unit are -700 mmHg and -650 mmHg, respectively.

The opening of the tip of the suction nozzle 50 is shown in FIG.
A cap 65 attached to the bottom of a vacuum blood collection tube as shown in FIG.
It can also be sealed. Further, it can be sealed with a brazing 66 as shown in FIG. 6A or a ferromagnetic material 67 as shown in FIG. Reference numeral 68 denotes a wax stopper that has been softened and opened.

Further, in the embodiment shown in FIG. 4, the sealing material 62 and the sealing material 63 may be adhered to each other, and the opening of the suction nozzle tip may be removed from the stopper 61 by the peeling operation of the sealing material 62.

[0059]

According to the present invention, plasma or serum for analysis can be easily prepared anywhere from a collected blood sample.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an example of a blood filtration unit used in the present invention.

FIG. 2 is a plan view of a lid of the blood filtration unit.

FIG. 3 is a bottom view of a lid of the blood filtration unit.

FIG. 4 is a longitudinal sectional view showing a state where the blood filtration unit is housed in a vacuum blood collection tube.

FIG. 5 is a cross-sectional view showing an example of a sealing material for sealing the opening of the suction nozzle tip.

FIG. 6 is a cross-sectional view illustrating an example of a sealing material that seals an opening of a suction nozzle tip.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Holder body 11 ... Glass fiber filter paper storage chamber 12 ... Microporous membrane storage chamber 13 ... Inclined part 14 ... Flange 15 ... Glass fiber filter paper mounting part 16 ... Funnel-shaped disk part 17 ... Nozzle-shaped blood inlet 19 ... Step Part 20 ... Lid 21 ... Outer wall 22 ... Inner wall 23 ... Cup 24 ... Flange 25 ... Rib 26 ... Protrusion 27 ... Plasma passage 28 ... Eave 29 ... Inflow section 30 ... Glass fiber filter paper 40 ... Polysulfone porous membrane (microporous membrane) 50 ... suction nozzle 51 ... large diameter part 60 ... vacuum blood collection tube 61 ... stopper (sealing material) 62 ... sheet (sealing material) 63 ... sheet (sealing material) 64 ... pull tab 65 ... cap (sealing material) 66 ... wax ( Sealing material) 67 ... Ferromagnetic material (sealing material) 68 ... Stopper

Claims (3)

[Claims] 1. A blood filtration unit containing a blood filtration material and provided with a nozzle for sucking blood and a filtrate outlet, wherein both the opening of the nozzle and the filtrate outlet are hermetically sealed. , Blood filtration unit inside 2. A plasma or serum collection tool stored in a container for storing blood collected by the blood filtration unit according to claim 1. 3. The plasma or serum collection tool according to claim 2, wherein the container has a sealed structure, the inside is in a depressurized state, and the nozzle opening is sealed by the sealed structure of the container.