JP2007333578A - Blood separation member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a blood separation member capable of separating blood plasma or serum from blood without requiring centrifugal separation and hardly causing a decrease in inspection precision caused by the adsorption of a measuring component. <P>SOLUTION: The blood separation member is used for separating blood plasma or serum from blood and has a coating layer comprising polyvinyl alcohol with a saponification value of 90% or below on its surface. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a blood separation member used for separating plasma or serum from blood, and more specifically, it is possible to separate plasma or serum from blood by preventing passage of blood cell components. The present invention relates to a blood separation member.

  Conventionally, centrifugation has been widely used to remove blood cell components from blood to obtain plasma or serum. However, the centrifuge method has been troublesome in the blood coagulation process and the process of transferring the supernatant plasma or serum after separation. Moreover, it takes time to obtain the test results, and a larger and more expensive centrifuge is required.

  Therefore, various separation membranes that can remove blood cell components from blood and obtain plasma or serum without using centrifugation have been proposed.

  For example, the following Patent Document 1 discloses hollow fibers having pores having a diameter of 0.05 to 1 μm, an outer surface opening ratio of 40% or less, an inner surface opening ratio of 60% or more, and a film thickness of 50 to 200 μm. A method for separating and collecting plasma from whole blood has been proposed. By using this hollow fiber, it is said that plasma can be separated at a high plasma separation rate.

On the other hand, Patent Document 2 below discloses a method for separating plasma or serum from whole blood using a glass fiber layer having an average fiber diameter of 0.2 to 5 μm and a density of 0.1 to 0.5 g / cm ^3. It is disclosed.

On the other hand, Patent Document 3 below discloses a plasma or serum separation filter in which a filter medium composed of a polymer microfiber assembly or a porous polymer is mounted in a container having an inlet and an outlet. A hydrophilic polymer is fixed to the polymer ultrafine fiber aggregate or porous polymer that is a filtering material in order to make it hydrophilic. The immobilized hydrophilic polymer moves blood through the filter medium, swells while separating or collecting plasma or serum, and automatically closes the filter by closing the filter. After obtaining a certain amount of plasma or serum, filtration automatically stops until the blood cell component reaches, so that it is possible to automatically prevent contamination of the blood cell component.
JP-B-2-23831 Japanese Patent Publication No. 6-64054 JP 11-285607 A

  However, in the method described in Patent Document 1, plasma components can be quickly separated and a small amount of sample can be analyzed in a short time. However, since expensive hollow fibers are used, the cost increases. I had to.

  In the method described in Patent Document 2, blood can be separated into blood cell components and plasma or serum, but the filtration rate is low and the filtration time cannot be shortened. Although it is possible to increase the filtration rate by applying pressure, hemolysis may occur or red blood cells may leak out.

  Furthermore, in the plasma or serum separation methods described in Patent Document 1 and Patent Document 2, when left for a long time after separation, hemolysis occurs, and there is a possibility that components in erythrocytes are mixed into plasma or serum.

  On the other hand, in the serum separation filter described in Patent Document 3, the hydrophilic polymer swells while blood is separated and collected into blood cell components and plasma or serum, and the filtration is automatically stopped by closing the filter. Even if it is left for a long time after separation, there is no possibility that components in erythrocytes are mixed into plasma or serum due to hemolysis.

  Here, blood is moved in the filter medium, and blood cell components in blood and plasma or serum are separated by a difference in moving speed. On the other hand, the hematocrit and blood having different viscosities have different moving speed differences, and in some cases, the filter may be clogged during the separation. If the filter is blocked during separation, the amount of sample that can be collected is greatly reduced.

  However, when a conventional blood separation member such as the separation membrane is used, blood components are adsorbed on the blood separation member, and accurate measurement results may not be obtained.

  In view of the current state of the prior art described above, the object of the present invention is not only to obtain a plasma or serum easily without requiring a centrifugation operation, but also to adsorb trace measurement components in blood to a blood separation member. An object of the present invention is to provide a blood separation member that can be suppressed and can be tested with high accuracy.

  The blood separation member according to the present invention is a blood separation member used for separating plasma or serum from blood, and has a coating layer made of polyvinyl alcohol having a saponification degree of 90% or less on the surface. To do. That is, the present invention is characterized in that the specific polyvinyl alcohol coating layer is provided on the surface of the blood separation member, thereby suppressing the adsorption of trace measurement components in the blood.

  Preferably, the saponification degree of the polyvinyl alcohol is in the range of 65 to 90%. If it is less than 65%, polyvinyl alcohol may be dissolved, and if it exceeds 90%, the effect of suppressing the adsorption of the test component cannot be sufficiently obtained.

  Preferably, the average degree of polymerization of polyvinyl alcohol is 300 or more, and more preferably in the range of 300 to 3500. When the average degree of polymerization is less than 300, polyvinyl alcohol tends to dissolve, which may adversely affect the test results. On the other hand, if the average degree of polymerization is larger than 3500, the adsorption suppression effect of the test component may be reduced.

  More preferably, the average degree of polymerization is 2800 or less, whereby adsorption of a trace measurement component can be more effectively prevented.

  As described above, the blood separation member according to the present invention has a polyvinyl alcohol coating layer of a specific additive on the surface, and the material itself of the blood separation member is not particularly limited. Therefore, one kind of material selected from the group consisting of a fiber aggregate, a porous body, and a film or molded body in which holes and grooves capable of inhibiting the passage of blood cells are formed is preferably used. By providing the specific polyvinyl alcohol coating layer on the plasma, according to the present invention, plasma or serum can be separated from the blood while effectively suppressing the adsorption of the trace measurement component in the blood.

  According to the blood separation member of the present invention, since the surface is coated with polyvinyl alcohol having a saponification degree of 90% or less, it is possible to reliably suppress the adsorption of trace measurement components in the blood to the blood separation member. . Therefore, plasma or serum can be separated from blood without using a centrifugal separation method, and the measurement accuracy of the test result can be dramatically increased.

  Hereinafter, the present invention will be clarified by describing specific embodiments of the present invention.

  As described above, the blood separation member according to the present invention is characterized in that the surface has a polyvinyl alcohol coating layer having a saponification degree of 90% or less. Therefore, the base material itself of the blood separation member is not particularly limited. Examples of the base material constituting such a blood separation member include a fiber aggregate, a porous body, and a membrane or molded body in which holes and grooves capable of prohibiting passage of blood cell components are formed. Examples of the fiber aggregate include an aggregate of ultrafine fibers that have been widely used conventionally. In addition, examples of the porous body include sintered bodies, porous films, and porous particles, and foams having open cells are also included in the porous body in a broad sense. In addition, examples of the material in which the hole or groove for prohibiting passage of the blood cell component is formed include a filter having such a hole and / or groove. Substantially, when blood is supplied to one side of the blood separation member, the blood cell component does not pass through the blood separation member, and as long as plasma or serum can be taken out to the other side, the base constituting the blood separation member The material is not particularly limited.

  In addition, the base material constituting the blood separation member is not limited to the one that separates the blood cell component and plasma or serum by capturing the blood cell component inside, but is based on the difference in moving speed between the blood cell component and plasma or serum component. You may isolate | separate both.

  The base material of the blood separation member can be divided into an asymmetric filter and a symmetric filter depending on the form. An asymmetric filter refers to a filter having a structure in which the pore diameter decreases from the inflow side to which blood is supplied to the outflow side. Other filters are collectively referred to as symmetric filters.

  As the symmetric filter, those having an average pore diameter of 1 μm or more and 10 or less are desirable. More preferably, they are 2 micrometers or more and 8 micrometers or less. If the average pore size is smaller than 1 μm, red blood cells may be hemolyzed. If the average pore size is larger than 10 μm, it may be difficult to separate blood cells from plasma or serum.

  Moreover, as said asymmetric filter, the thing of the range whose average hole diameter is 0.01 micrometer or more and 10 micrometers or less is preferable, More preferably, they are 0.1 micrometer or more and 6 micrometers or less. If the average pore diameter is smaller than 0.01 μm, blood cell components may be clogged, and separation may not be possible, and hemolysis may occur. When the average pore diameter is larger than 10 μm, the separation accuracy between blood cells and plasma or serum may be deteriorated.

  In the case where the blood separation member is made of a fiber assembly, it is preferable that ultrafine fibers having an average fiber diameter in the range of 0.5 to 3.0 μm are accumulated. If the average fiber diameter is smaller than 0.5 μm, hemolysis is likely to occur when blood is separated. When the average fiber diameter is larger than 3.0 μm, it is necessary to increase the density of the fibers in the blood separation member in order to separate blood cells from plasma or serum. In addition, the amount of fiber to be used increases, which may increase the cost. In order to further enhance the separation effect, the average fiber diameter is more preferably in the range of 0.5 to 2.5 μm.

The blood separating member is used such that when blood is supplied to one side, plasma or serum is separated from blood cell components and taken out from the other side. Therefore, the blood separation member is usually filled in a container such as a cylindrical container. In this case, the average density of the blood separation member filled in the container is preferably in the range of 0.1 to 0.5 g / cm ³ . If the average density is lower than 0.1 g / cm ³ , separation may not be performed effectively, and the amount of plasma or serum obtained may be reduced. When the average density is higher than 0.5 g / cm ³ , the load on red blood cells is increased, and hemolysis is likely to occur. In order to separate blood more efficiently, the average density is preferably in the range of 0.15 to 0.40 g / cm ³ .

  The blood separation member according to the present invention may be a combination of the symmetric filter and the asymmetric filter.

  As described above, the blood separation member according to the present invention has a surface coated with polyvinyl alcohol having a saponification degree of 90% or less. In this case, the saponification degree is preferably 65% or more and 90% or less. By setting it to 65% or more and 95% or less, dissolution of polyvinyl alcohol hardly occurs, adsorption of the test component to the blood separation member can be surely suppressed, and a highly accurate test result can be obtained. If it is less than 65%, polyvinyl alcohol is dissolved, which may adversely affect the test result. If it exceeds 90%, the effect of suppressing the adsorption of the test component is reduced.

  The average degree of polymerization of the polyvinyl alcohol is preferably 300 or more, more preferably 300 or more and 3500 or less. As described above, by setting the average degree of polymerization in the range of 300 to 3500, dissolution of polyvinyl alcohol can be suppressed, and adsorption of test components to the blood separation member can be reliably suppressed.

The method of coating the polyvinyl alcohol is not particularly limited. 1) A method of immersing the member constituting the blood separation member in a solution in which polyvinyl alcohol is dissolved, removing moisture, and drying. 2) Container in advance 3) A method in which a solution of polyvinyl alcohol is passed through under pressure with a base material to be a blood separation member set in, etc. 3) Polyvinyl alcohol is added in a state where the base material is previously set in a container or the like, and then centrifuged. Examples include a method of removing moisture and drying.
However, in manufacturing the blood separation member, the method of coating the surface of the substrate with polyvinyl alcohol is not limited to these.

  The polyvinyl alcohol coating is preferably uniformly applied to the entire blood separating material. This is because if the coating is unevenly applied, the pressure may be excessively applied at the time of blood separation in a portion where the coating amount is large, and hemolysis may occur. Further, it is preferable to remove moisture as much as possible before drying. This is because if excessive moisture remains, a film is formed in the void portion of the blood separating material, and blood may not be separated normally. Regarding the removal of moisture, it is preferably set appropriately by each processing method.

The coating amount of polyvinyl alcohol is preferably 0.1 to 30 mg, more preferably 0.5 to 20 mg per 1 m ² of the surface area of the blood separating material. This is because when the coating amount is less than 0.1 mg, the effect of suppressing the adsorption of the test component is reduced, and when it is 30 mg or more, polyvinyl alcohol is dissolved, which may adversely affect the test result.

  As described above, the blood separation member is used for the purpose of separating and taking out blood plasma or serum from blood cell components from the other side when blood is supplied to one side, and is usually stored in a container. Used. As such a container, when blood is supplied to one side of the blood separation member, the blood enters the blood separation member without bypassing the side of the blood separation member, and plasma or serum is supplied from the other side. Various containers that can be taken out can be used. Although it does not specifically limit as such a container, For example, cylindrical bodies, such as a cylindrical shape, are generally used. That is, in the cylindrical body, the blood separating member can be accommodated, blood can be introduced into one side, and plasma or serum can be taken out from the other side. Although the specific shape as a container using such a cylindrical body is not specifically limited, For example, the syringe-shaped blood separation container 1 shown in FIG. 1 can be illustrated. The blood separation container 1 has a cylindrical container body 2. An opening 2a is provided at one end of the container body 2, and the other end side is an outlet side, and has a hole 2b having a smaller diameter than the opening 2a. A blood separation member 3 configured according to the present invention is accommodated in the container body 2. Then, plasma or serum can be separated from the blood by pushing the operating member 7 having the piston 5 and the operating rod 6 in the direction of the arrow while the blood 4 is supplied onto the blood separating member 3.

  The blood separation container is not limited to the blood separation container 1 shown in FIG. 1, and may be in the form of a holder that holds a membrane filter, for example. That is, various blood separation containers can be used according to the form of the blood separation member.

  Next, specific examples and comparative examples will be given to clarify the effects of the present invention.

Example 1
0.55 g of a polyester fiber having an average fiber diameter of 1.8 μm was immersed in a 0.5 wt% aqueous solution of polyvinyl alcohol having a saponification degree of 71.5% and an average polymerization degree of 500 for 1 hour. Next, after removing the water, it was dried in an oven at 60 ° C. overnight. The coating amount of polyvinyl alcohol per unit area after drying was 5.6 mg / m ² .

(Example 2)
0.55 g of a polyester fiber having an average fiber diameter of 1.8 μm was immersed in a 0.5 wt% aqueous solution of polyvinyl alcohol having a saponification degree of 80% and an average polymerization degree of 500 for 1 hour. Next, after removing the water, it was dried in an oven at 60 ° C. overnight. The coating amount of polyvinyl alcohol per unit area after drying was 6.0 mg / m ² .

(Example 3)
0.55 g of a polyester fiber having an average fiber diameter of 1.8 μm was immersed in a 0.5 wt% aqueous solution of polyvinyl alcohol having a saponification degree of 88% and an average polymerization degree of 1000 for 1 hour. Next, after removing the water, it was dried in an oven at 60 ° C. overnight. The coating amount of polyvinyl alcohol per unit area after drying was 7.0 mg / m ² .

Example 4
0.55 g of polyester fiber having an average fiber diameter of 1.8 μm was immersed in a 0.5 wt% aqueous solution of polyvinyl alcohol having a saponification degree of 88% and an average polymerization degree of 2800 for 1 hour. Next, after removing the water, it was dried in an oven at 60 ° C. overnight. The coating amount of polyvinyl alcohol per unit area after drying was 10.3 mg / m ² .

(Example 5)
0.55 g of a polyester fiber having an average fiber diameter of 1.8 μm was immersed in a 0.05% by weight aqueous solution of polyvinyl alcohol having a saponification degree of 71.5% and an average polymerization degree of 500 for 1 hour. Next, after removing the water, it was dried in an oven at 60 ° C. overnight. The coating amount of polyvinyl alcohol per unit area after drying was 0.5 mg / m ² .

(Example 6)
0.55 g of a polyester fiber having an average fiber diameter of 1.8 μm was immersed in a 1.5 wt% aqueous solution of polyvinyl alcohol having a saponification degree of 71.5% and an average polymerization degree of 500 for 1 hour. Next, after removing the water, it was dried in an oven at 60 ° C. overnight. The coating amount of polyvinyl alcohol per unit area after drying was 15.6 mg / m ² .

(Comparative Example 1)
0.55 g of a polyester fiber having an average fiber diameter of 1.8 μm was immersed in a 0.5 wt% aqueous solution of polyvinyl alcohol having a saponification degree of 98.5% and an average polymerization degree of 500 for 1 hour. Next, after removing the water, it was dried in an oven at 60 ° C. overnight. The coating amount of polyvinyl alcohol per unit area after drying was 6.2 mg / m ² .

(Comparative Example 2)
0.55 g of a polyester fiber having an average fiber diameter of 1.8 μm was immersed in a 0.5% by weight aqueous solution of polyvinyl alcohol having a saponification degree of 40% and an average polymerization degree of 600 for 1 hour. Next, after removing the water, it was dried in an oven at 60 ° C. overnight. The coating amount of polyvinyl alcohol per unit area after drying was 5.1 mg / m ² .

(Comparative Example 3)
0.55 g of a polyester fiber having an average fiber diameter of 1.8 μm was immersed in a 0.005 wt% aqueous solution of polyvinyl alcohol having a saponification degree of 71.5% and an average polymerization degree of 500 for 1 hour. Next, after removing the water, it was dried in an oven at 60 ° C. overnight. The coating amount of polyvinyl alcohol per unit area after drying was 0.05 mg / m ² .

(Comparative Example 4)
0.55 g of a polyester fiber having an average fiber diameter of 1.8 μm was immersed in a 3.0 wt% aqueous solution of polyvinyl alcohol having a saponification degree of 71.5% and an average polymerization degree of 500 for 1 hour. Next, after removing the water, it was dried in an oven at 60 ° C. overnight. The coating amount of polyvinyl alcohol per unit area after drying was 33.4 mg / m ² .

(Evaluation experiment)
The blood separation members prepared in Examples 1 to 6 and Comparative Examples 1 to 4 are schematically shown in FIG. However, the cylindrical container body 2 having a diameter of 12.5 mm was filled and compressed and filled so as to have a filling density of 0.27 g / cm ³ .

  After filling, heparin lithium was added to the blood collected from the volunteer in advance so as to be 5 units / ml, 2.5 mL of the blood was added to the cylindrical container body 2, and the blood was separated by pressurization with a piston. Specimens in serum obtained by separation were measured. Upon measurement, total protein, AST, ALT, total cholesterol, and neutral fat were measured as clinical test items. As a control, a commonly used biochemical vacuum blood collection tube Insepack II-D was used.

  Serum could be separated in any of the samples of Examples 1 to 6 and Comparative Examples 1 to 4, but clear hemolysis was observed in Comparative Example 2 having a low degree of saponification.

  Further, in the samples of Comparative Examples 1, 3, and 4, a decrease in the value considered to be the effect of adsorption was observed with respect to the measured value when the control blood collection tube for each test item was used. About -6, there was almost no difference from the measured value in the control.

The typical front sectional view showing an example of the blood separation container in which the blood separation member of the present invention is stored.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Blood separation container 2 ... Container main body 2a ... Opening 2b ... Hole 3 ... Blood separation member 4 ... Blood 5 ... Piston 6 ... Operation rod 7 ... Operation part

Claims (6)

A blood separation member used to separate plasma or serum from blood,
A blood separation member having a coating layer made of polyvinyl alcohol having a saponification degree of 90% or less on the surface.   The blood separation member according to claim 1, wherein the saponification degree is in a range of 65 to 90%.   The blood separation member according to claim 1 or 2, wherein the average degree of polymerization of the polyvinyl alcohol is 300 or more.   The blood separation member according to any one of claims 1 to 3, wherein the average degree of polymerization of the polyvinyl alcohol is in the range of 300 to 3500. The blood separation member according to any one of claims 1 to 4, wherein a coating amount of the polyvinyl alcohol is in a range of 0.1 to 30 mg per 1 m ² of a surface area of the blood separation material.   The coating layer made of the polyvinyl alcohol is provided on the surface of one material selected from the group consisting of a fiber aggregate, a porous body, and a film or a molded body in which grooves or holes that do not allow blood cells to pass through are formed. The blood separation member according to any one of claims 1 to 5.

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