JP3350722B2 - Antithrombotic mesh filter for body fluid treatment circuit and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antithrombotic mesh filter for a body fluid treatment circuit and a method for treating the same, and more particularly, a thrombus adheres to a mesh filter used in a body fluid treatment circuit such as hemodialysis and plasma exchange. The present invention relates to an antithrombotic mesh filter for a body fluid treatment circuit and a method for treating the same, which can prevent the occurrence of the thrombus as much as possible.

[0002]

2. Description of the Related Art Artificial organ dialysis is a method in which blood in the body is taken out of the body, passed through a blood circulation circuit, and then returned to the body to perform blood dialysis. , A drip chamber, and a mesh filter is used in the drip chamber.
FIG. 1 is a schematic view of a drip chamber, and a mesh filter 2 is provided below the drip chamber 1 so as to cover a mesh filter support 7. Blood enters through the blood inlet 4, passes through the mesh filter 2, and exits through the blood outlet 5.

According to the standard for dialysis of artificial organs, the mesh filter 2 is described as follows: "The blood circuit must be provided with a drug solution injection and blood collection unit, and the venous circuit must be provided with an air trap and a filter net. Eye size is 210μm
(70 mesh) It must be finer or of a structure having performance equivalent to this. Filtration nets (filters) are usually made of nylon (trade name) or polyester to remove foreign matter, particles such as blood clots, and air bubbles. It is desirable that the yarn diameter is uniform and the surface is smooth, and a monofilament consisting of one yarn is more preferable than a multifilament formed by yarn in terms of blood compatibility. The product is manufactured based on this rule.

[0006] A mesh filter 2 which is a kind of biocompatible material removes foreign substances in blood, particles such as blood coagulation, air bubbles, and the like. This biocompatible material is generally composed of a nonionic material, and the following reports have been made regarding the adsorption of proteins to the surface of such a material. "The highest concentration of serum albumin in blood plasma first adsorbs to the surface of the material, but it also desorbs and delays the adsorption of small amounts of proteins. Among the existing proteins, their molecular weight, shape, charge, surface hydrophilicity / hydrophobicity,
A specific protein group reaches adsorption equilibrium depending on the easiness of denaturation. As shown in FIG. 2, a protein adsorbed to a surface having a high concentration of dissociating groups by Coulomb force will undergo some degree of denaturation, but a protein adsorbed to a nonionic material surface by van der Waals force or the like will be affected. Changes in higher-order structure have not been studied in detail yet (see "Biocompatible Materials" (published by the Japan Standards Association)). (In FIG. 2,
8 is a biocompatible material, and 9 is a biological component. )

In recent years, heparin,
There is a tendency to reduce the amount of anticoagulants such as Fusan and Fragmin, but on the other hand, there is also a method of manufacturing a mesh filter having antithrombotic properties by coating the mesh filter with a hydrophilic polymer. Conceivable.

[0006]

However, every time dialysis is repeated, water is removed, the hematocrit value fluctuates, and the blood viscosity increases. So during extracorporeal circulation,
Drugs are administered to control the blood clotting time within a certain range. Under these circumstances, in particular, patients requiring a platelet aggregation inhibitor and an oral anticoagulant, such as hypercoagulable patients and local heparinization when combined with protamine sulfate (Regional Heparinization)
Blood coagulation in the blood circuit and in the dialyzer (in the blood circuit, blood coagulation occurs mostly around the mesh filter portion and the welded portion in the chamber body).
The blood circuit must be replaced during dialysis, which causes a problem that the burden on the patient and the burden on the hospital are large. Further, the method of coating the mesh filter with a hydrophilic polymer is not preferable because it has disadvantages such as cost and labor.

Accordingly, the present inventors have eliminated the necessity of exchanging a blood circuit by directly preventing the attachment of a thrombus to the mesh filter portion in the chamber main body in the above-mentioned blood circuit, thereby eliminating the need for replacing the blood circuit. As a result of various studies to reduce the burden on hospitals and the burden on hospitals,
It has been found that by subjecting a mesh filter made of a specific material to discharge treatment, it is possible to obtain a mesh filter free of thrombus adhesion, and that it is economically inexpensive, can be easily and easily mass-produced without labor. Thus, the present invention has been completed. Accordingly, a first problem to be solved by the present invention is to provide an anti-thrombosis mesh for a body fluid treatment circuit capable of minimizing the generation of thrombus during body fluid treatment in the blood circulation circuit and preventing the attachment of plasma proteins to the mesh filter. It is to provide a filter.
A second problem to be solved by the present invention is to provide a method of treating an antithrombotic mesh filter for a body fluid treatment circuit which is economically inexpensive, can be easily and easily mass-produced without labor. .

[0008]

The above object of the present invention is to provide:
The invention is achieved by the following inventions.

[0009] (1) antithrombotic body fluid processing circuit, characterized in that the body fluid treatment mesh filters obtained from polyamide or polyester Le whether we selected biocompatible materials impart anti-thrombotic and corona discharge treatment Mesh filter. (2) The antithrombotic mesh filter for a body fluid treatment circuit according to the above (1), wherein the polyester is polyethylene terephthalate. (3) The antithrombotic mesh filter for a humor treatment circuit according to the above (1) or (2), wherein the surface of the humor treatment mesh filter has a hydrophilic property. (4) a living body selected from polyamide or polyester
Mesh filter for body fluid treatment obtained from compatible materials
Processing strength is ^{3W / m 2 / min~150W / m} 2 / mi
with n corona discharge, it features and to that body fluid antithrombotic Messi for processing circuit <br/> Interview filter manufacturing method of treating the surfaces of the mesh filter. (5) The processing power is 600 W to be performed at normal temperature and atmospheric pressure.
1200 W, treatment intensity 100 W / m ² / min ~ 15
5. The method for producing an antithrombotic mesh filter for a body fluid treatment circuit according to claim 4, wherein both sides of the mesh filter are treated using corona discharge treatment at 0 W / m ² / min and a frequency of 10 to 20 KHZ.

[0010]

When DETAILED DESCRIPTION OF THE INVENTION The present invention will be explained in further detail below, the body fluid treatment circuit antithrombotic mesh filter for the present invention, a body fluid treatment mesh obtained from polyamide or polyester Le whether we selected biomaterials The filter is provided with antithrombotic properties by corona discharge treatment, whereby each of the above materials is subjected to a sufficient corona discharge treatment to suppress adhesion of thrombus or plasma proteins. . Further, among the above biocompatible materials, polyvinyl acetate, polyurethane, polyacrylonitrile, ethylene-vinyl alcohol copolymer, cellulose acetate, regenerated cellulose or silicone rubber are also used in artificial kidneys and exhibit excellent antithrombotic properties. Is preferred.

The biocompatible material used in the present invention is selected from polyamide or polyester. It is preferable to form these materials into a filament consisting of one thread to form a net. In the present invention, a corona discharge treatment may be performed in the state of the net, and then the filter may be formed. Alternatively, a corona discharge treatment may be performed after the net is formed in the filter. Preferably the latter. In the corona discharge treatment, a roller that supports the substrate is used as an electrode, electrodes facing the roller are provided, and a corona discharge is generated by applying a high voltage between these electrodes, and the corona is moved to the front of the substrate while moving the substrate. A method of performing a discharge treatment is usually used. It is considered that as a result of the corona discharge treatment, oxidation and ionization occur on the surface of the base material to be activated.

[0012]

The electric power required for the corona discharge treatment of the present invention is as follows:
Usually, it is 600 W to 1200 W, and the processing strength required for processing the material is 3 W / m ² / min to 150 W / m.
² / min. If the line Uco corona discharge at atmospheric pressure at room temperature varies depending on the material, 3W / m ² / mi
n to 150 W / m ² / min, for example, in the case of polyethylene, 3 W / m ² / min to 15 W / m ² / mi
n and 30 W / m ² / m in the case of polyester.
in to 60 W / m ² / min. In the present invention, the contact angle of water on the surface of the mesh filter can be reduced to 60 degrees or less, preferably 55 degrees to 40 degrees by such corona discharge treatment. The angle is more preferably 50 to 40 degrees, and may be 40 degrees or less as long as a value of 40 degrees or less can be obtained by these corona discharge treatments.

[0014] used in the present invention, <br/> row Uco corona discharge treatment at atmospheric pressure at room temperature, the processing conditions processing power 600W~
1200 W (processing intensity 100 to 150 W / m ² / mi
n), frequency 10-20 KHZ, distance 0.2 m from electrode
It is performed by processing both sides at room temperature with a diameter of m to 1.5 mm. As a result, oxygen in the air reacts with the surface to generate hydroxyl groups, carboxyl groups, and the like, and the surface becomes hydrophilic. Therefore, the mesh filter has antithrombotic properties.

[0015]

The discharge treatment method of the mesh filter for a body fluid treatment circuit according to the present invention is characterized in that a corona discharge is performed. Specifically, the treatment by the corona discharge generated between the electrodes in the atmosphere is performed by a mesh filter. of a body fluid treatment circuit for mesh filter corona discharge treatment method characterized by applying to both sides, the process conditions in the atmospheric pressure processing power 600W～1200W (treatment intensity 100 under normal temperature
150 W / m ² / min), frequency 10-20 KHZ,
A corona discharge treatment method for a mesh filter for a bodily fluid treatment circuit, characterized in that both surfaces are processed at a distance of 0.2 mm to 1.5 mm from the electrode. In particular, in the case of polyethylene terephthalate, not only an effect of cleaning organic substances on the surface can be obtained, but also excellent durability can be obtained.

(Operation) In the present invention, the bodily fluid circulating in the bodily fluid treatment circuit removes minute foreign substances and thrombus clots in the bodily fluid by a mesh filter in the circuit, and the mesh filter is subjected to corona discharge treatment. By being applied, the surface has hydrophilicity, so that the body fluid does not easily pass through the mesh filter and is hardly clotted.
Furthermore, since it has a negative potential, formation of a thrombus and adhesion of plasma proteins hardly occur. Further, according to the discharge treatment method of the mesh filter for a body fluid treatment circuit of the present invention, the organic substances present on the surface of the biocompatible material selected from the aforementioned materials are washed and removed. In particular, when polyethylene terephthalate is used as a fiber, not only the surface is not fluffy but also excellent durability can be obtained.

[0018]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but these are only examples of the present invention, and the present invention is not limited thereto.

Reference Example 1 [Measurement of Contact Angle] Two types of films, a polyester film (Lumirror, manufactured by Toray Industries, Inc.) and a polypropylene film (IPP, manufactured by Okura Industries Co., Ltd.), before and after corona discharge treatment, respectively. Prepared. Here, the corona discharge treatment conditions were as follows: treatment power 950 W, treatment intensity 115 W / m ² /
min, frequency 10 KHz, distance between electrodes 0.1-0.
Performed at 2 mm. The contact angles of the two types of films before and after the corona discharge treatment were measured 10 times, and the average is shown in Table 1. Here, the measurement of the contact angle is based on JIS L1
092-1986 Performed according to the waterproof test method for textiles (room temperature 20 ° C., solution: ion-exchanged water, liquid temperature 17).
° C).

[0020]

[Table 1]

[Measurement of wettability] The wettability of two types of polyester mesh subjected to corona discharge treatment was measured according to JIS K676.
It carried out according to the wetting test method of the polyethylene and polypropylene film of 8-1977. Here, the corona discharge treatment conditions were a treatment power of 1100 W and a treatment intensity of 100 W / m.
² / min, frequency 12 KHz, distance between electrodes 0.1 to
Performed at 0.2 mm. Two types of corona-discharge treated films (Product No .: polyester TNO70SS and TO8
0SS), the surface tension was measured and is shown in Table 2.
The test is performed by dropping 10 drops of the reagent on the mesh and counting the number of permeated reagents.

[0022]

[Table 2]

EXAMPLE 1 A 70-mesh filter made of polyethylene terephthalate (wire diameter 55 ± 6 μm, opening 310) under the condition of a mesh cloth which is a product of the present invention.
± 30 μm) as the corona discharge treatment,
0W, processing power 100W / m ² / min, frequency 12K
Hz and a distance between the electrodes of 0.1 to 0.2 mm, and the conventional product was subjected to artificial dialysis using an untreated polyethylene terephthalate 70 mesh filter (wire diameter 72 ± 7 μm, opening 292 ± 30 μm). A blood circuit thrombus test was performed. Table 3 shows the rate of occurrence of coagulation and residual blood in the chamber for the artificial dialysis blood circuit and the situation.

[Status of Clotting / Blood in Drip Chamber] ---: There is no clotting / bleeding. -: Almost no clot or residual blood. +: There is blood clot or residual blood. ++: There is considerable coagulation and residual blood. The normal value of the hematocrit value (capillary method) is:
39-52%, female: 35-48%.

[0025]

[Table 3]

[0026]

[0027] The product and conventional products was subjected to corona discharge treatment in Example 1, statistical methods (chi ² test)
Table 4 shows the test results. In addition, statistical methods (χ
² ) are described in “Statistical Method (Published by the Japan Standards Association): Test on Contingency Table”.

[0028]

[Table 4] As is evident from Table 4, the product of the present invention has χ ₀ ² = 1.
8.4 and is, of conventional even in the assay by the contingency table goods χ ²
Since the value is larger than (1, 0.05) = 3.84 (hazard rate 5%), it is understood that the product of the present invention is effective. Therefore, the product of the present invention has little residual blood and is excellent as an antithrombotic mesh filter .

[0029]

[0030]

EFFECTS OF THE INVENTION The mesh filter subjected to the discharge treatment as in the present invention has excellent antithrombotic properties, can minimize the generation of thrombus during the treatment of body fluids in the blood circulation circuit, and has the plasma and protein against the mesh filter. This has an excellent effect of preventing the adhesion of water. Further, according to the discharge treatment method of the present invention, there is an excellent effect that it is economically inexpensive, can be easily and easily mass-produced without any trouble.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a chamber in which a conventional mesh filter is installed.

FIG. 2 is a schematic cross-sectional view showing a charge relationship between a biocompatible material and a biological component.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Drip chamber main body 2 Mesh filter 3 Cap 4 Blood inlet 5 Blood outlet 6 Pressure monitor line tube 7 Mesh filter support 8 Biocompatible material 9 Biological component (for example, protein etc.)

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kiichi Sugiyama 2-350 Toyota, Hino-shi, Tokyo Inside NBC Industry Co., Ltd. (72) Inventor Eiji Kawabata 2-chome Toyota, Hino-shi, Tokyo Reference No. 50 at 3NBC Industrial Co., Ltd. (56) References JP-A-4-200475 (JP, A) JP-A-7-204263 (JP, A) JP-A-3-218771 (JP, A A) JP-A-6-304243 (JP, A) WO 94/17904 (WO, A1) (58) Fields investigated (Int. Cl. ⁷ , DB name) A61L 33/00 A61M 1/34

Claims (5)

(57) [Claims] 1. A antithrombotic mesh body fluid processing circuit, characterized in that the body fluid treatment mesh filters obtained from polyamide or polyester Le whether we selected biocompatible materials impart anti-thrombotic and corona discharge treatment filter. 2. The antithrombotic mesh filter for a body fluid treatment circuit according to claim 1, wherein the polyester is polyethylene terephthalate. 3. The antithrombotic mesh filter for a body fluid treatment circuit according to claim 1, wherein the surface of the mesh filter for treating body fluid has hydrophilicity. 4. A material selected from polyamide or polyester.
Mesh for body fluid treatment obtained from biocompatible materials
Ter the processing strength of ^{3W / m 2 / min~150W / m} 2
/ Using corona discharge min, features and to that body fluid processing circuit antithrombotic <br/> mesh filter manufacturing method for treating the surfaces of the mesh filter. 5. The process performed at normal temperature and atmospheric pressure, wherein the processing power is 60
0W～1200W, processing strength is 100W / m ² / min
~150W / m ² / min and a frequency 10~20KHZ
The method for producing an antithrombotic mesh filter for a body fluid treatment circuit according to claim 4 , wherein both surfaces of the mesh filter are treated by using the corona discharge treatment of (1) .