JPS61154541A - Vacuum blood sampling tube - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a blood test container, and particularly to a vacuum blood collection tube used for collecting a whole blood sample from a subject and separating serum by centrifugation.

(Prior Art) With the remarkable progress in testing technology, blood tests such as serum biochemical tests, serum immunological tests, and blood cell tests have become widely used, and are useful for disease prevention and early diagnosis. Most blood tests are serum tests, and the serum required for these tests is usually 2.
Blood collected in a blood test container is coagulated and then centrifuged.

It is separated from blood clots (gel-like lumps containing fibrin and blood cells) with different specific gravity.

Blood has traditionally been collected from subjects using a syringe, but recently a vacuum blood collection tube has been used to collect blood. To collect blood using a vacuum blood collection tube, blood is collected into the vacuum blood collection tube under reduced pressure via a dedicated blood collection holder.

Vacuum blood collection tubes are made of glass and synthetic resins such as polymethyl methacrylate.

However, even if blood is collected into vacuum blood collection tubes made of these materials, it takes a considerable amount of time for the blood to coagulate and separate into serum and blood clots, and the drawback is that the serum necessary for testing cannot be quickly obtained. has. This becomes a problem especially when there is a need to carry out an inspection urgently. Even with glass vacuum blood collection tubes, which are said to have a short blood coagulation time, it takes 40 to 60 minutes for the blood to coagulate after blood is drawn.9 If a synthetic resin vacuum blood collection tube is used, it can be left for more than 4 hours. It takes time. Furthermore, when a vacuum blood collection tube made of such a material is used, gel-like fibrin or blood clots tend to adhere firmly to the tube wall during blood coagulation, resulting in a reduction in the amount of serum collected. In addition, fibrin tends to remain in the serum, which causes problems in serum biochemical tests. Even if a glass vacuum blood collection tube, which is said to have relatively good serum separation, is used, the separation is extremely poor at low temperatures of 15° C. or lower, especially in the winter when the temperature is low.

On the other hand, inorganic fine particles such as glass are attached to the tube wall to shorten the blood coagulation time, silicone oil,
Separation of serum has been improved by dispensing a separation agent containing silicon compound powder or the like into a blood collection tube. Such separating agents have thixotropic properties and are adjusted to have a specific gravity intermediate between serum and blood clots. Therefore.

After the collected blood has coagulated, when the blood collection tube is placed in a centrifuge, the separating agent moves to the middle of the serum layer and the blood clot layer, allowing the blood serum layer to be separated from the blood clot layer. If it takes time to subject the serum separated in this way to various tests, the blood collection tube is usually used as is.

Stored at a temperature of 4°C. However, the shelf life is relatively short, about 48 hours in glass blood collection tubes and even in polymethyl methacrylate vacuum blood collection tubes.

It is 72 hours at most. , (Problems to be Solved by the Invention) The present invention solves the above-mentioned conventional drawbacks, and its purpose is to coagulate a collected whole blood sample in a short period of time and to make it more effective by centrifugation. An object of the present invention is to provide a vacuum blood collection tube that can effectively separate serum and blood clots. Still another object of the present invention is to maintain serum quality without degrading even if it is stored as it is at low temperature for a long time after centrifugation.

Therefore, it is an object of the present invention to provide a vacuum blood collection tube that is effective as a serum storage container.

(Means for Solving the Problems) The vacuum blood collection tube of the present invention has a bottomed tubular container whose inside can be evacuated and a sealable stopper that maintains the reduced pressure state of the container. The material is polyethylene terephthalate or polyethylene terephthalate copolymer, and the material of the sealable stopper is butyl rubber or chlorinated butyl rubber, thereby achieving the above object.

As the adsorbent inorganic substance applied to the inner wall surface of the vacuum blood collection tube of the present invention, a fine powder of a water-insoluble inorganic substance that can be used as an adsorbent in a vessel is used. Examples of adsorbent inorganic materials include glass, silica, kaolin, and celite bentonite. The particle size is preferably 50 μm or less, and the average particle size is preferably 10 μm or less. In particular, when silica powder is used as the adsorbent inorganic material, blood coagulates in a short time. In particular, porous silica containing 20% by weight or more of amorphous components exhibits excellent effects.

The adsorbent inorganic substance has the effect of promoting activation of blood coagulation factors and promoting aggregation of platelets when it comes into contact with blood. The speed of blood coagulation varies depending on the surface area and shape of the adsorbent inorganic material.

By the way, when blood coagulates, a complex is first formed by three substances in the blood, factor xn (contact factor), prekallikrein, and polymer kininogen, and is adsorbed on the surface of a foreign object. Next.

Factor X■ is activated and blood coagulation begins. Therefore, if the surface area of the adsorbent inorganic material is too small, the complex will be difficult to adsorb, resulting in a slow blood coagulation rate. Conversely, even if the surface area of the adsorbent inorganic material is too large.

Factor XII, prekallikrein, and high-molecular-weight kininogen are adsorbed without a complete complex being formed, and therefore factor XII is not activated.

Eventually, the rate of blood clotting slows down. As described above, the adsorptive inorganic substance needs to have an appropriate surface area and surface shape.

The surface shape of the adsorptive inorganic material, such as its surface area and surface pore size, is
It can be expressed by linseed oil absorption or BET specific surface area. The linseed oil absorption amount of the adsorbent inorganic substance is measured according to Japanese Industrial Standards -5101.

First, 1 to 5 g of adsorbent inorganic material is placed on a glass plate (approximately 250 x 2
50 x 5 m), drop linseed oil little by little into the center of the sample from a billet, and mix the whole thing thoroughly with a spatula each time. Set as the end point.

Based on the amount of linseed oil used, m7 of linseed oil is required to soften 100 g of sample! Calculate the number and use this as the linseed oil absorption amount.

The BET specific surface area value is Brunauer-Emmet
This value is obtained from the multilayer adsorption theory proposed by T-Teller, and the theory is published in the Journal
of American Chemical
ety 60.309 (1938); 59.268
2 (1937) and others. The BET specific surface area value is calculated from the amount of gas adsorbed on the surface of an adsorbent inorganic material, the equilibrium pressure at that time, and the saturated vapor pressure of the adsorbed gas, and calculates the amount of gas that can cover the surface as a monomolecular layer, and then calculates the amount of gas that can cover the surface as a monomolecular layer. This is a value calculated by multiplying by the average cross-sectional area of the molecule. Nitrogen gas is used as adsorption gas.

Oxygen gas, argon gas, methane gas, etc. are used. According to this method, the surface area value including pores, which cannot be measured depending on the linseed oil absorption amount, can be measured.

The adsorbent inorganic substance applied to the inner wall surface of the vacuum blood collection tube of the present invention has a linseed oil absorption amount of 20 to 40 m1/100 g, B
ET specific surface area value 5.000-30. ooocm”
/ G There is.

-i, when the collected blood comes into contact with a foreign object.

Prior to the blood coagulation phenomenon, proteins such as albumin, globulin, and various blood coagulation factors are immediately adsorbed to the surface of the foreign object. At that time, the protein molecule may undergo a conformational change. especially.

Since the activation mechanism of blood coagulation factors is an oxygen reaction, it is greatly affected, and in some cases, the blood coagulation function is impaired. In addition, platelets adhering to adsorbed globulin and albumin, which have undergone large conformational changes, undergo abnormal melting and deformation.

A phenomenon occurs in which the polymerized and precipitated fibrin chains strongly adhere to adsorbent inorganic substances. If such a phenomenon occurs in a blood collection tube, blood clots and serum will not be separated even if centrifugation is performed.

Changes in protein conformation are caused by hydrophobic interactions, hydrogen bonding interactions, and
Caused by interactions such as electrostatic interactions. Among these, the influence of electrostatic interactions between adsorbent inorganic substances and protein molecules is relatively large. When a protein molecule approaches an adsorbent inorganic substance, a dipole moment group is induced in the adsorbent inorganic substance with a corresponding distribution due to the polar groups of the protein molecule. If the adsorptive inorganic substance is non-conductive, even if a dipole moment group is induced, the potential distribution of the protein molecule and the potential distribution of the adsorbent inorganic substance will lack consistency with each other. Therefore, the protein molecule becomes locally distorted,
A conformational change occurs. However, when the adsorptive inorganic material has conductivity, the consistency of the potential distribution between the protein molecule and the adsorptive inorganic material is maintained, and changes in protein conformation can be prevented. The adsorptive inorganic substance in the present invention has relatively high conductivity.

Its specific resistance value is 1×10 10 Ω·cm or less. Therefore, the protein molecules do not change their conformation, and the blood coagulation function decreases.

Separability does not deteriorate.

The amount of adsorbent inorganic material applied to the inner wall of the container is 1 x 10-6
~1xlO-'g/cIiI. If the amount is too low, a sufficient activation effect on blood coagulation factors will not be obtained, and if the amount is excessive, adsorbent inorganic substances may be mixed into the serum, which may interfere with serum tests.

In addition to adsorbent inorganic substances, a surfactant is applied to the inner wall of the vacuum blood collection tube. The surfactant has the effect of preventing blood clots from adhering to the inner wall of the container and preventing hemolysis into serum during centrifugation. As the surfactant, a nonionic surfactant is used. especially.

Fatty acid esters of polyglycerin such as stearic acid polyglyceride and oleic acid polyglyceride; fatty acid esters of sorbitol such as sorbitan monostearate and sorbitan monooleate; polyether-modified silicones such as polyethylene glycol-modified silicone oil and polypropylene glycol-modified silicone oil Oil is preferably used.

The amount of surfactant applied to the inner wall of the container is l x 10-1
0 to 1 xlQ-'/crA. If it is too small, the effect of preventing blood clots from adhering to the inner wall of the container will not be sufficient, and if it is too large, the surfactant may be mixed into the serum and interfere with serum testing. If no surfactant is added, the rate of blood coagulation will be accelerated due to adsorbent inorganic substances, but since adsorbent inorganic substances have the effect of causing blood clots formed by coagulation to adhere to the inner wall surface of the container, it is difficult to apply centrifugation. However, it is difficult to separate coagulated blood into serum and blood clots. Furthermore, red blood cells may be destroyed by the strong abrasion stress generated between the blood clot and the adsorbent inorganic material on the inner wall of the container during centrifugation, and hemoglobin may dissolve into the serum.

A septum-forming agent is further provided inside the vacuum blood collection tube of the present invention. The partition forming agent contains a thixotropic agent and a viscous liquid, and has thixotropic properties. The septum-forming agent is located between serum and blood clot when centrifuged, and has the function of forming septa. In many biochemical tests, only serum is used, and serum is collected with a pipette after centrifugation using a blood test container.However, once serum and blood clots are completely separated using a septum-forming agent, serum can be fractionated by decantation. Therefore, a one-part collection operation does not take much time, and blood clot components do not become mixed into the serum by moving the container after centrifugation.

As a thixotropic agent for partition wall forming agents.

Silica, alumina, glass, talc, kaolin.

bentonite, titania, zirconium, asbestos,
There are inorganic powders such as carbon black, and organic powders such as styrene resins, acrylic resins, and vinyl chloride resins. Among these thixotropic agents, fine silica powder is preferably used. The silica fine powder is a fine powder containing silicic anhydride as a main component, which has been subjected to hydrophobization treatment by grafting reaction or coupling reaction as necessary. The average particle size of the thixotropic agent is 1
It is 0-3 μm to 100 μm. If the particle size is smaller than 104 μm, it is difficult to handle, and when mixed with the viscous liquid described below, it tends to aggregate and form secondary particles, and is not uniformly dispersed. If it is larger than 100 μm, the dispersion stability in a viscous liquid will be poor, and the partition forming agent as a whole will lack uniform fluidity.

The specific surface area of the thixotropic agent is 10 to 500rd.
/g. When the specific surface area is within this range, excellent thixotropy can be obtained. Specific surface area is 10r
If it is smaller than rf/g, if the thixotropic agent is an inorganic fine powder, it will not be compatible with the viscous liquid (and will easily cause sedimentation. If the specific surface area is larger than 500 m/g, it will tend to aggregate; Not uniformly dispersed in viscous liquids.

The viscous liquid may or may not have a strong interaction with the thixotropic agent. Here, "having a strong interaction with the thixotropic agent" means that the thixotropic agent is mixed with a viscous liquid and dispersed uniformly, and then the rotation speed is 4.00 Orpm in a centrifuge with arm length Locm. This refers to a case where no bias is observed in the distribution of the components of the mixed metal even after centrifugation for 30 minutes. The cause of such interaction is not clear, but! ! It is assumed that the effect is mainly due to hydrogen bonding between materials having aqueous groups, and the cohesive force caused by the molecular structure between materials without hydrophilic groups.

Examples of viscous liquids that have a strong interaction with thixotropic agents include acid-modified products of liquid polymeric substances such as acrylic resin oligomers, polyester oligomers, liquid polyisoprene, liquid polybutene, and polybutadiene; maleic acid-modified products; Animal and vegetable oils such as soybean oil, linseed oil, safflower oil, and fish oil; acid-modified products of these animal and vegetable oils; liquid polymeric substances such as liquid polybutene and liquid polybutadiene.

Examples include epoxy-modified products of the above animal and vegetable oils. When the thixotropic agent is an organic powder, it is like styrene oligomer for polystyrene.

For example, oligomers of the same type as the thixotropic agent are preferably used. The viscosity of the viscous liquid that has a strong interaction with the thixotropic agent is preferably 200 cps or more. When a viscous liquid having such a viscosity is used, the thixotropic agent and the viscous liquid will not separate.

Viscous liquids that do not have strong interactions with thixotropic agents can also be used in the presence of the water-insoluble amine compounds described below. Examples of such viscous liquids include liquid polymer substances such as liquid paraffin, liquid polyisoprene, liquid polybutene, and liquid polybutadiene, styrene oligomers, and chlorinated products thereof. When the thixotropy imparting agent is a styrene resin, liquid paraffin or its chlorinated product is used. The viscosity of these viscous liquids is 1,000
It is preferable that it is more than cps.

If the viscous liquid that has a strong interaction with the above-mentioned thixotropic agent and the viscous liquid that does not have a strong interaction with the thixotropic agent have good compatibility, a mixture of these can also be used. . Here, "having good compatibility" refers to a state in which phase separation does not occur even if the two viscous liquids are mixed and uniformly dispersed and then left at room temperature for one week. Use of these mixtures provides excellent viscosity stability over time. The mixing ratio is appropriately set in consideration of the strength of interaction with each thixotropic agent. Generally, 10 to 600 parts by weight of a viscous liquid that does not have a strong interaction with a thixotropic agent is mixed with 100 parts by weight of a viscous liquid that has a strong interaction with a thixotropic agent.

When the partition forming agent contains a water-insoluble amine compound,
The stability of the viscosity of the partition wall forming agent over time is further improved.

As the water-insoluble amine compound, one having one or more alkyl groups having 8 or more carbon atoms in the molecule is suitable. These include, for example, dodecylamine, tetradecylamine, hexadecylamine, octadecylamine, dodecyldimethylamine, tetradecyldimethylamine, octadecyldimethylamine.

There are polyoxyethylene octadecylamine and trioctylamine.

Water-insoluble amine compounds have the property of being adsorbed onto the surface of the thixotropic agent and also interact with viscous liquids, so by adding them, the viscosity of the partition-forming agent can be stabilized over time. gender is ensured. In particular, amines having an alkyl group having 8 or more carbon atoms are highly water-insoluble and do not dissolve in separated serum or plasma. Furthermore, when adsorbed onto the surface of the thixotropy-imparting agent, the long-chain alkyl group of the amine compound is considered to have the function of stabilizing the interaction between the thixotropy-imparting agents. Therefore, the viscosity of the partition forming agent is extremely stable over time, and as a result, centrifugal separability and partition wall stability are excellent.

In the partition forming agent, the thixotropic agent is contained in an amount of 2 to 15 parts by weight per 100 parts by weight of the viscous liquid. The water-insoluble amine compound is added in an amount of 0.02 to 5 parts by weight per 100 parts by weight of the viscous liquid. The specific gravity of the partition wall forming agent thus obtained is 1.03 to 1.08 at room temperature, typically at 20°C. This corresponds to a value approximately intermediate between the specific gravity of serum and the specific gravity of blood clots.

Polyethylene terephthalate having the following structural formula is used as the material for the bottomed tubular container of the vacuum blood collection tube of the present invention.

Because polyethylene terephthalate is highly crystalline.

In order to suppress this, 1.4
- A polyethylene terephthalate copolymer copolymerized with a crystallization inhibitor such as cyclohexanedimethanol may be used. Polyethylene terephthalate has excellent gas barrier properties and can maintain a predetermined degree of reduced pressure. It also has much better impact resistance than glass or polymethyl methacrylate, and there is no risk of breakage due to reduced pressure. Also regarding disposal after use.

Incineration, which cannot be done with glass vacuum blood collection tubes, becomes possible.

To obtain the vacuum blood collection tube of the present invention, first, an adsorbent inorganic substance, a surfactant, and a partition forming agent are applied to the inner wall surface of the bottomed tubular container. Specifically, for example, the above-mentioned adsorbent inorganic substance is dissolved or decomposed in a suitable binder or solvent, and the solution is spray coated or dip coated onto the inner wall surface. A surfactant is mixed in advance with polyethylene terephthalate copolymer, and a container is formed using an appropriate molding method such as injection molding, blow molding, compression molding, transfer molding, vacuum forming, or casting molding. An adsorbent inorganic material dispersed in a binder or solvent may be spray coated or dip coated. The septum-forming agent may be dispensed into the container from the beginning, or may be added when the collected blood is coagulated and then centrifuged.

A sealable stopper that maintains the reduced pressure state of a vacuum blood collection tube is obtained by vulcanization molding of butyl rubber or chlorinated butyl rubber according to a conventional method. To reduce the pressure inside the blood collection tube, it is sufficient to seal the blood collection tube with the rubber stopper in the reduced pressure container.

(Effect) When blood is collected from the subject into the thus obtained vacuum blood collection tube whose interior is in a reduced pressure state and left at room temperature, approximately 2
Blood clots in 0-30 minutes. When this is centrifuged, it is separated into serum and blood clots.

Since the material of the container of the vacuum blood collection tube of the present invention is polyethylene terephthalate or polyethylene terephthalate copolymer, which has low hydrophilicity, conventional materials with high hydrophilicity 9
For example, unlike glass or polymethyl methacrylate, no adsorption layer of water molecules is formed on the inner wall surface that comes into contact with blood.

Therefore, the serum separating agent and the inner wall surface of the blood collection tube come into close contact, completely separating serum and blood clots. Therefore, it is considered that inorganic ions from the blood clot do not enter the serum layer via the water molecule adsorption layer on the inner wall.

Therefore, serum separated by centrifugation can be stored at low temperature for a long time. When the vacuum blood collection tube of the present invention is used, it can be stored at 4°C for 340 hours or more. The number of holes is approximately 7 times larger than when using a glass blood collection tube. On the other hand, when a conventional vacuum blood collection tube into which a serum separation agent is dispensed is used, an adsorption layer of water molecules is formed, so the serum separation agent does not adhere firmly to the inner wall of the blood collection tube.

It is thought that a sufficient blocking effect is not obtained and inorganic ions etc. diffuse from the blood clot into the serum layer. the result.

Separated serum cannot be stored for a long time.

In this way, by using the vacuum blood collection tube made of the specific material of the present invention, the collected whole blood sample can be coagulated in a short time, and serum and blood clots can be effectively separated by centrifugation. After 2 minutes.

It is possible to use the blood collection tube as it is as a serum storage container.

(Example) The invention will be explained below with reference to examples.

Ohba flame polyethylene glycol modified silicone oil and fine silica powder (average particle size 4.0 μm; linseed oil absorption 3)
0μ/! /100g i B ET specific surface area value 1.2×
10'cm"/g i specific resistance value 2.6 x 10'Ω・
A Freon dispersion liquid was prepared in which 0.5% by weight of 0.5% by weight of each of the following components was dispersed. This dispersion liquid was coated on the inner wall surface of a 10 m/sized spitz made of polyethylene terephthalate. After thoroughly drying the tube, the inside was evacuated and the tube was sealed with a butyl rubber stopper to prepare a vacuum blood collection tube. The degree of internal vacuum was set so that the amount of blood collected was 6 ml. After collecting injected fresh blood using the vacuum blood collection tube, it was left to stand at 20°C, and the time required for the whole blood to become completely fluid was measured. After blood coagulation.

Immediately centrifugation was performed at a rotation speed of 3,000 rpm for 5 minutes, and the state of serum separation was observed. The results are shown in Table 1. As is clear from Table 1, when the obtained vacuum blood collection tube was used, blood coagulation was extremely rapid and the serum separation state was also good.

Daishi fllJ 2 Specific gravity at 20℃ is 1.02 and viscosity is 10.0OOc
70 parts by weight of chlorinated polybutene of PS, 21 parts by weight of epoxidized soybean oil with a specific gravity of 1.0 at 20°C and a viscosity of 1 + 700 cps, 9 parts by weight of hydrophobized finely powdered silica, and 0.2 parts by weight of trioctylamine. The mixture was kneaded using a three-roll kneader to obtain a partition wall-forming agent having a specific gravity of 1.06 at 20°C.

1 g of this septum-forming agent was injected into the same Freon dispersion-coated tube as in Example 1, and the amount of blood collected was 6.
The degree of internal vacuum was set so that the volume was 1.5 ml, and the container was sealed with a butyl rubber stopper. After blood was collected using the vacuum-guaranteed tube thus obtained, the blood coagulation property and serum separation state were observed in the same manner as in Example 1. The results are shown in Table 1. Then,
Immediately after centrifugation to observe its performance as a serum storage container.

Serum on the 3rd, 7th, and 14th day of the cold storage at 4°C was collected, and LDH and K listed in the biochemical test items were measured. The results are shown in Table 2. As is clear from the results in Table 1, the obtained vacuum blood collection tubes showed rapid blood coagulation and good serum separation. Furthermore, as is clear from the results in Table 1 and Table 2, LDH showed a stable value, making it a good serum storage container.

Blood was collected using a 1L commercially available 6 MF glass vacuum blood collection tube, and blood coagulation was determined in the same manner as in Example 1.

The serum separation status was observed. The results are shown in Table 1.

Next, the performance as a serum storage container was tested in the same manner as in Example 2. The results are shown in Table 2.

Table 1 Table 2 □ (Effects of the Invention) According to the present invention, as described above, the collected whole blood sample can be coagulated in a short period of time, and serum and blood clots can be effectively separated by centrifugation. A vacuum blood collection tube is obtained. Such a vacuum blood collection tube is also effective as a storage container for serum after centrifugation, and the obtained serum can be stored at low temperature for a long time.

that's all

Claims (1)

[Claims] 1. The tubular container has a bottomed tubular container whose inside can be evacuated and a stopper that can be tightly closed to maintain the reduced pressure state of the container, and the material of the tubular container is polyethylene terephthalate or polyethylene terephthalate copolymer. A vacuum blood collection tube, wherein the material of the sealable stopper is butyl rubber or chlorinated butyl rubber. 2. The vacuum blood collection tube according to claim 1, wherein a surfactant and an adsorbent inorganic substance are applied to the inner wall surface of the container. 3. Linseed oil absorption amount of the adsorbent inorganic substance is 20 to 40 m
l/100g, and the BET specific surface area value is 5,000~
30,000 cm^2/g of the vacuum blood collection tube according to claim 2. 4. The specific resistance value of the adsorptive inorganic substance is 1×10^1^0Ω
- The vacuum blood collection tube according to claim 2, which is less than cm. 5. The vacuum blood collection tube according to claim 2, wherein the surfactant is a nonionic surfactant. 6. The surfactant is 1×10^-^1^0 to 1×10
Vacuum blood collection tube according to claim 2, given at a rate of ^-^3 g/cm^2. 7. The adsorbent inorganic substance is 1 x 10^-^6 to 1 x 10^
Vacuum blood collection tube according to claim 2, given at a rate of -^3 g/cm^2. 8. The vacuum blood collection tube according to claim 2, wherein a septum-forming agent is provided in the container. 9. The vacuum blood collection tube according to claim 8, wherein the septum-forming agent contains a thixotropic agent and a viscous liquid. 10. The vacuum blood collection tube according to claim 8, wherein the septum-forming agent contains a thixotropic agent, a viscous liquid, and a water-insoluble amine.