KR20140108921A - Multi-layer Filter for Removing Leukocytes and Preparation Method thereof - Google Patents

Abstract

The present invention relates to a filter for removing leukocytes and a manufacturing method thereof and, more specifically, to a filter for removing leukocytes excellent in a rate of removing leukocytes and a rate of collecting red blood cell in blood by using a filter for removing leukocytes with a multi-layered structure including a microporous fiber layer, a nanofiber layer, and a coating layer, and to a manufacturing method thereof. A filter for removing leukocytes with a multi-layered structure manufactured by the present invention is excellent in a rate of removing leukocytes and a rate of collecting red blood cell in blood compared to an existing filter for removing leukocytes, and useful as a blood filter due to unique blood compatibility of filter material.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a filter for removing leukocytes in a multi-

The present invention relates to a filter for removing leukocytes in a multilayered structure, and more particularly, to a filter for removing leukocytes in a multi-layered structure, and more particularly to a filter for removing leukocyte from a blood, comprising a microporous fiber layer, a nanofiber layer, The present invention relates to a filter for removing leukocyte having excellent multi-layer structure and a manufacturing method thereof.

In general, blood transfusion is a necessary measure for trauma bleeding and surgical patients. In place of whole blood transfusion which has caused side effects after past blood transfusion, transfusion has been mainly performed to provide only effective components for treating diseases. However, blood transfusions such as erythrocyte transfusion, platelet transfusion, and plasma transfusion have been reported to cause side effects after transfusion.

Examples of such side effects include infantile exacerbation, allogeneic immune response, acute pulmonary embolism, GVHD, allergic reactions, anaphylactic reactions, viral and bacterial infections, and immunosuppression, ≪ RTI ID = 0.0 > Therefore, in many countries, it is mandatory to remove leukocytes from whole blood or component blood before transfusion to minimize these side effects.

Methods for removing leukocytes from the blood to date include, for example, removal by centrifugation, removal by a filter, and removal by dextran. Among them, a filter is used for reasons of convenience, low cost and high removal efficiency A method of removing leukocytes is mainly adopted.

As to various methods for removing leukocytes by a filter, various literatures are known, and it is known that a polyester nonwoven fabric having an average fiber diameter of 0.3 to 3.0 μm and a knitting index y of 50 or less corresponding to a thickness of 0.3 mm and a packing ratio of 0.05 to 0.30 The leukocyte removal performance was improved by using a leukocyte removal filter having a simple structure, but the blood collection rate such as the red blood cell recovery rate was not satisfactory (Patent Document 1).

Further, by using a filter for removing leukocytes, which has a three-layer structure of a water-dispersible polyurethane nanofiber nonwoven fabric layer, a polyester meltblown nonwoven fabric layer and a polyester spunbond nonwoven fabric layer, the leukocyte removal rate is 95% Although the reference value is exceeded, there is room for improvement (according to the American Blood Bank Association, the leukocyte removal rate is 95% or more and the erythrocyte recovery rate is 90% or more), and the red blood cell recovery rate is still low.

It has been investigated to increase the leukocyte removal rate and the platelet passing rate at the same time by coating the nonwoven fabric, which is the base material of the leukocyte removal filter, so that the fibers coated with the anti-thrombogenic material such as polyether urethane, polyhydroxyethyl methacrylate, It is also known to collect leukocytes and lymphocytes which contain little red blood cells and platelets by using a nonwoven fabric as a filter material. However, when this filter is used, the leukocyte removal rate is low (Patent Document 3).

In addition, when the filter for removing leukocytes is used, in order to facilitate passage of blood through the filter, and to increase the removal efficiency of leukocytes and the recovery rate of component blood such as erythrocytes, the filter substrate is generally coated with a nonionic hydrophilic polymer and a basic hydrophilic polymer or organic acid However, such a coating method has a disadvantage in that it is difficult to control the coating components separately and the control of each of the coating components.

On the other hand, polyethylene glycol and polypropylene glycol have been reported as a material capable of preventing thrombus formation and protein aggregation by coating on a product which is in contact with blood. In the pharmaceutical industry, it is used as a drug coating, a binder and a lubricant. In addition, polyethylene glycol and polypropylene glycol have an advantage that a monomer having a double bond can be easily bonded to the terminal, and they can form a copolymer with another monomer having a double bond by a known polymerization method such as emulsion polymerization (Patent Document 4).

Therefore, in the present invention, a multilayered filter for removing leukocytes is prepared by coating the surface of a filter substrate with a copolymer comprising polyethylene glycol homopolymer, polypropylene glycol homopolymer, or polyethylene glycol or polypropylene glycol having a double bond at the terminal Respectively. In particular, it is useful for blood filters because it has high leukocyte removal rate as well as high red blood cell recovery rate.

Patent Document 1: Registration No. 10-1038248 Patent Document 2: Japanese Patent Application Laid-Open No. 10-2010-0023155 Patent Document 3: JP-A-55-129755 Patent Document 4: JP-A-7-25776

SUMMARY OF THE INVENTION It is an object of the present invention to provide a filter for removing leukocyte and a method of manufacturing the filter for removing leukocyte having a multilayered structure having a higher leukocyte removal rate and a better red blood cell recovery rate as compared with a filter for removing leukocyte The purpose.

In order to achieve the above object, the present invention provides a microporous fibrous layer, a nanofiber layer, and a polyethylene glycol homopolymer coating layer, a polypropylene glycol homopolymer coating layer, or a polyether glycol or polypropylene glycol derivative having a double bond at a terminal And a coating layer which is a copolymer of acrylic or methacrylic monomers.

The microporous fiber layer is a nonwoven fabric having an average fiber diameter of 0.5 to 5 μm.

The microporous fibrous layer is a nonwoven fabric having a thickness of 10 to 200 탆.

The nonwoven fabric may be any one selected from the group consisting of polyester, polyurethane, polyolefin, polyamide, polystyrene, polyacrylonitrile, cellulose, and cellulose acetate.

Wherein the nanofiber layer has an average fiber diameter of 50 to 1,000 nm.

The nano fiber layer has a thickness of 1 to 50 m.

Wherein the nano fiber layer is any one selected from the group consisting of polyurethane, polyacrylate, polymethacrylate, polyester, polyether, polyolefin, and polyamide.

The polyether glycol or polypropylene glycol derivative having a double bond at the terminal thereof is selected from the group consisting of polyethylene glycol-acrylic acid, polyethylene glycol-methacrylic acid, polyethylene glycol-methacrylate, polyethylene glycol-methyl methacrylate, and polypropylene glycol- Acrylate, and acrylate.

The acrylic or methacrylic monomer may be selected from the group consisting of acrylic acid, methacrylic acid, acrylamide, methacrylamide, allylamine, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, dimethylaminopropyl methacrylate, 3- 2-hydroxypropyl methacrylate, vinylpyridine, and 4-vinylimidazole.

The copolymer forming the coating layer has a weight average molecular weight of 50,000 to 200,000.

The present invention also provides a method for producing a microporous fibrous layer, comprising the steps of: i) subjecting a nonwoven fabric having an average fiber diameter of 0.5 to 5 占 퐉 to a plasma or corona discharge treatment to form a microporous fiber layer;

ii) forming a nanofiber layer having an average fiber diameter of 50 to 1,000 nm by electrospinning on the microporous fiber layer in the step i); And

iii) a coating layer of a polyethylene glycol homopolymer coating layer, a polypropylene glycol homopolymer coating layer, or a copolymer coating layer of a polyether glycol or a polypropylene glycol derivative having a double bond at the terminal end and an acrylic or methacrylic monomer on the nanofiber layer of the step ii) Forming a filter for removing leukocyte in the multi-layered structure.

The multilayered filter for removing leukocytes according to the present invention is superior in blood leukocyte removal rate and erythrocyte recovery rate to conventional leukocyte removal filters and is useful as a blood filter since it possesses the blood compatibility inherent to the filter material.

Hereinafter, the filter for removing leukocytes of the multi-layered structure according to the present invention and the method for fabricating the same will be described in detail.

First, the present invention has a microporous fiber layer as a filter substrate. The microporous fiber layer may be formed of a nonwoven fabric, a woven fabric or a woven fabric having an average fiber diameter of 0.5 to 5 占 퐉, among which a nonwoven fabric is more preferable.

When the mean fiber diameter of the microporous fiber layer is less than 0.5 탆, the mechanical strength is lowered. Thus, there is a disadvantage that the fibers are broken due to collision with leukocyte and other blood cell components during treatment of the blood, or the platelet adsorption amount is increased. The microporous fiber layer exceeding 5 μm is not suitable because it decreases the adsorption amount and adsorption rate of leukocyte and decreases the open area ratio of the filter material and interferes with the flow of blood containing leukocyte.

The thickness of the nonwoven fabric constituting the microporous fiber layer is preferably 10 to 200 m, more preferably 50 to 100 m. If the thickness of the nonwoven fabric is less than 10 μm, the leukocyte removal rate is lowered. If the thickness of the nonwoven fabric exceeds 200 μm, the pressure loss may be excessively increased due to the passage of blood.

As the material of the nonwoven fabric, any one selected from the group consisting of polyester, polyurethane, polyolefin, polyamide, polystyrene, polyacrylonitrile, cellulose, and cellulose acetate may be used without limitation. desirable.

Next, the multilayered filter for removing leukocytes according to the present invention comprises a nanofiber layer. The nanofiber layer is located on the front side of the blood and contacts the blood first. The multi-layered filter for removing leukocytes according to the present invention has an advantage that the leukocyte removal rate and the erythrocyte recovery rate can be remarkably increased by increasing the surface area by which the leukocyte can be adsorbed by providing the nanofiber layer. The nanofiber layer preferably has an average fiber diameter of 50 to 1,000 nm. If the average fiber diameter is less than 50 nm, the micropore size between the nanofibers is too small to cause the problem that the adsorbed white blood cells block the micropores, And a nanofiber layer having an average fiber diameter exceeding 1,000 nm is not preferable because the adsorption rate of leukocytes is lowered.

The thickness of the nanofiber layer is preferably 1 to 50 mu m, more preferably 5 to 20 mu m. If the thickness of the nanofiber layer is less than 1 μm, the leukocyte removal rate is decreased. If the thickness of the nanofiber layer is more than 50 μm, a pressure loss due to the passage of blood may occur.

As the material of the nano fiber layer, any one selected from the group consisting of polyurethane, polyacrylate, polymethacrylate, polyester, polyether, polyolefin, and polyamide can be used. Among them, polymethyl methacrylate More preferable.

The filter for removing leukocytes in the multilayered structure according to the present invention may further comprise a polyethylene glycol homopolymer coating layer, a polypropylene glycol homopolymer coating layer, or a polyether glycol or polypropylene glycol derivative having a double bond at the terminal and an acrylic or methacrylic monomer Of the present invention. Polyethylene glycol, polypropylene glycol or derivatives thereof are known to have excellent blood compatibility and have been used for many years as medical materials. In the present invention, since the coating layer contains polyethylene glycol or polypropylene glycol units, it exhibits a high platelet adhesion inhibition effect due to excellent blood compatibility.

The polyether glycol or polypropylene glycol derivative having a terminal double bond as a monomer constituting the copolymer coating layer of the present invention may be polyethylene glycol-acrylic acid, polyethylene glycol-methacrylic acid, polyethylene glycol-methacrylate, polyethylene glycol-methyl Acrylate, methacrylate, and polypropylene glycol-methacrylate.

An acrylic or methacrylic monomer is used as a monomer which reacts with a polyether glycol or a polypropylene glycol derivative having a double bond at the terminal to form a copolymer. In particular, an acrylic or methacrylic monomer containing an organic acid or an acrylic or methacrylic monomer containing a nitrogen atom is preferred. Examples of these monomers include acrylic acid, methacrylic acid, acrylamide, methacrylamide, allylamine, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, dimethylaminopropyl methacrylate, 3- Hydroxypropyl methacrylate, vinylpyridine, and 4-vinylimidazole can be used.

Polymer materials, which are widely used as filter materials for removing leukocytes, are generally hydrophobic rather than hydrophilic and may be useful for removing white blood cells. However, since leukocytes are removed, other blood components such as platelets or red blood cells tend to be adsorbed. Platelets or red blood cell recovery rates have a trade-off relationship. On the contrary, as the surface of the blood filter material is hydrophilic, the platelets are hardly activated and the adsorption of platelets and hydrophobic proteins is inhibited by the hydrogen bonding of water and the surface of the blood filter material. Therefore, in the present invention, Glycol or polypropylene glycol and a hydrophobic unit such as methyl methacrylate and acrylic or methacrylic monomer to form a copolymer coating layer, thereby increasing the leukocyte removal rate and improving the red blood cell recovery rate. A blood filter is provided.

The copolymer forming the coating layer of the present invention preferably has a weight average molecular weight of 50,000 to 200,000. If the weight average molecular weight of the copolymer is less than 50,000, elution as a coating material can not be allowed, Has a weight average molecular weight of more than 200,000, the solubility thereof is low and it is difficult to obtain a coating liquid.

The present invention also provides a method for producing a microporous fibrous layer, comprising the steps of: i) subjecting a nonwoven fabric having an average fiber diameter of 0.5 to 5 占 퐉 to a plasma or discharge treatment to form a microporous fiber layer;

ii) forming a nanofiber layer having an average fiber diameter of 50 to 1,000 nm by electrospinning on the microporous fiber layer in the step i); And

iii) a coating layer of a polyethylene glycol homopolymer coating layer, a polypropylene glycol homopolymer coating layer, or a copolymer coating layer of a polyether glycol or a polypropylene glycol derivative having a double bond at the terminal end and an acrylic or methacrylic monomer on the nanofiber layer of the step ii) Forming a filter for removing leukocyte in the multi-layered structure.

In the present invention, the nonwoven fabric is subjected to plasma or corona discharge treatment to improve the adhesion of the polymer coating layer, and the corona discharge treatment is more advantageous for the convenience of the apparatus. The corona discharge treatment is carried out using a general corona discharge treatment apparatus at a discharge amount of 50 to 500 W (m ² / min) and a discharge degree of 10 to 500 W / cm ² .

In the present invention, the nanofiber layer is formed on the microporous fiber layer by electrospinning. As the electrospinning device, any electrospinning device including a polymer solution radiation part, a high voltage generating part and a nanofiber collecting part can be used. The spinning conditions are arbitrarily adjustable without any particular limitation.

Meanwhile, in order to form a copolymer coating layer on the nanofiber layer, a copolymer is synthesized by reacting a polyether glycol or a polypropylene glycol derivative having a double bond at the terminal thereof with an acrylic or methacrylic monomer, A polymer solution may be prepared by dissolving the copolymerized polymer in an organic solvent and then a known solution such as a spray coating method, a plasma coating method, a dip coating method, or the like may be used. Coat uniformly using the method.

Also, the copolymer may be formed directly on the nanofiber layer of the nonwoven fabric by an in situ method using gamma rays or plasma.

Hereinafter, embodiments of a filter for removing leukocyte and a method of manufacturing the same according to the present invention will be concretely described.

[ Manufacturing example ] Copolymer solution preparation for coating layer formation

50 mmol of polyethylene glycol-methacrylate (PEG-MA) and 50 mmol of acrylic acid (AA) as monomers were placed in a 1-L four-neck round bottom flask with 700 mL of water and stirred for 30 minutes under a nitrogen atmosphere. 1 x ^10-3 mol / L aqueous solution of potassium persulfate was added as a polymerization initiator and emulsion polymerization was carried out at 60 DEG C for 2 hours to obtain a bead-like copolymer. The copolymer solution was prepared by dissolving the obtained polyethylene glycol-methacrylate / acrylic acid copolymer (PEG-MA / AA) at a concentration of 1.5 wt% in an aqueous ethanol solution.

Further, as a combination of the monomers, polyethylene glycol-methacrylate (PEG-MA) and methacrylic acid (MAA), polyethylene glycol-methyl methacrylate (PEG-MMA), acrylamide (AAM), polyethylene glycol- (PEG-AA) and vinyl pyridine (VP), poly (ethylene glycol) -acrylic acid (PEG-AA) and dimethylaminoethyl methacrylate (DMAEMA) (PPG-MA) and acrylic acid (AA), and polypropylene glycol-methacrylate (PPG-MA) and methacrylic acid (MAA) As a result of measuring the molecular weight by GPC, the weight average molecular weight of the copolymer was in the range of 50,000 to 200,000.

[ Example  1] Manufacture of multi-layered filter for removing leukocytes

A polyester nonwoven fabric having an average fiber diameter of 0.5 to 5 占 퐉 was prepared, and the surface of the nonwoven fabric was treated with a general discharging treatment apparatus under the conditions of a discharging amount of 50 W (m ² / min) and a discharging degree of 100 W / cm ² to prepare a microporous fiber layer . A polymethylmethacrylate nanofiber layer having an average fiber diameter of 50 to 1,000 nm was formed on the surface-treated polyester nonwoven fabric by ordinary electrospinning to a thickness of 1.5 탆. A 1.5 wt% solution of the polyethylene glycol-methacrylate / acrylic acid copolymer obtained from the above Preparation Example was spray coated on a filter substrate and dried to prepare a multilayer filter for removing leukocytes.

[Examples 2 to 10] Manufacture of a filter for removing leukocytes in a multilayer structure

A multilayered filter for removing leukocytes was prepared in the same manner as in Example 1, except that a material as described in Table 1 was used as a material for forming a copolymer or a single-polymer coating layer.

Example Copolymer coating layer material Example 2 1.5% by weight solution of PEG-MA / MAA copolymer Example 3 1.5% by weight solution of PEG-MMA / AAM copolymer Example 4 1.5% by weight solution of PEG-MMA / ALAM copolymer Example 5 A 0.5 wt% solution of PEG-AA / DMAEMA copolymer Example 6 0.5% by weight solution of PEG-AA / VP copolymer Example 7 0.5% by weight solution of PPG-MA / AA copolymer Example 8 0.5% by weight solution of PPG-MA / MAA copolymer Example 9 0.5% by weight solution of PEG homopolymer Example 10 0.5% by weight solution of PPG homopolymer

[Measurement example] Contact angle, leukocyte removal rate, erythrocyte recovery rate

The contact angle, the leukocyte removal rate and the erythrocyte recovery rate of the multi-layered leukocyte removal filter prepared in Examples 1 to 10 were measured and the contact angle of the filter substrate was measured to determine the leukocyte removal filter according to the present invention. The characteristics attributed to hydrophilicity or hydrophobicity were confirmed as compared with the blood filter. The leukocyte removal filters prepared in Examples 1 to 10 were laminated on a filter housing, and leukocyte counts and erythrocyte counts before and after passing through the filters were measured, and leukocyte removal rates and erythrocyte recovery rates were calculated therefrom. As a comparative example, commercially available Purecell RC manufactured by Paul Inc. was adopted, and the results are shown in Table 2 below.

Example Contact angle ( ^o ) Leukocyte removal rate (%) Red blood cell recovery (%) Example 1 41 99 96 Example 2 35 97 94 Example 3 37 98 97 Example 4 44 99 94 Example 5 46 99 96 Example 6 42 98 93 Example 7 36 98 95 Example 8 48 99 95 Example 9 52 99 98  Example 10 60 99 97        Comparative Example 35 97 95

Leukocyte removal rate = (leukocyte count before filter passing - leukocyte count after passing filter) / (leukocyte count before filter passing) x 100

Red blood cell recovery rate = (number of red blood cells before passing through filter - number of red blood cells after passing through the filter) / (number of red blood cells before passing the filter) x 100

As shown in Table 2, the filters for removing leukocytes of the multilayered structures manufactured from Examples 1 to 10 of the present invention were measured at the same or almost similar values of contact angle as those of the commercialized blood filter of Comparative Example, And the hydrophobic part, it was confirmed that not only the efficiency of leukocyte removal but also the adsorption of red blood cells or platelets can be suppressed. In addition, the leukocyte removal efficiency of the present invention was much higher than that of the commercialized blood filter, and the filtration efficiency of the leukocyte removal filter according to the present invention was remarkably higher than that of the commercialized blood filter. Examples 1, 5, 9, Although the white blood cell removal rate is 99% and the erythrocyte recovery rate is also in the range of 96% to 98%, although the recovery rate of red blood cells due to the partial adsorption of red blood cells may be low even if the leukocyte removal rate is high, %, Respectively.

Therefore, the multi-layered leukocyte removal filter manufactured by the present invention is expected to be useful for a blood filter having not only a leukocyte removal rate but also an erythrocyte recovery rate due to its unique structure.

Claims (11)

i) a microporous fiber layer;
ii) a nanofiber layer; And
iii) a coating layer composed of a polyethylene glycol homopolymer coating layer, a polypropylene glycol homopolymer coating layer, or a copolymer of a polyether glycol or a polypropylene glycol derivative having a double bond at the terminal thereof with an acrylic or methacrylic monomer, Removal filter. The leukocyte removal filter according to claim 1, wherein the microporous fiber layer is a nonwoven fabric having an average fiber diameter of 0.5 to 5 占 퐉. The leukocyte removal filter according to claim 1, wherein the microporous fiber layer is a nonwoven fabric having a thickness of 10 to 200 탆. The multilayer structure according to claim 2 or 3, wherein the nonwoven fabric is any one selected from the group consisting of polyester, polyurethane, polyolefin, polyamide, polystyrene, polyacrylonitrile, cellulose, and cellulose acetate Of leukocyte removal filter. The leukocyte removal filter according to claim 1, wherein the nanofiber layer has an average fiber diameter of 50 to 1,000 nm. The leukocyte removal filter according to claim 1, wherein the nanofiber layer has a thickness of 1 to 50 μm. The multilayered structure of claim 1, wherein the nanofiber layer is any one selected from the group consisting of polyurethane, polyacrylate, polymethacrylate, polyester, polyether, polyolefin, and polyamide. Filter. The polyether glycol or polypropylene glycol derivative as set forth in claim 1, wherein the polyether glycol or polypropylene glycol derivative having a double bond at the terminal thereof is selected from polyethylene glycol-acrylic acid, polyethylene glycol-methacrylic acid, polyethylene glycol-methacrylate, polyethylene glycol- And polypropylene glycol-methacrylate. ≪ Desc / Clms Page number 24 > The method of claim 1, wherein the acrylic or methacrylic monomer is selected from the group consisting of acrylic acid, methacrylic acid, acrylamide, methacrylamide, allylamine, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, Wherein the polyolefin is any one selected from the group consisting of 3-dimethylamino-2-hydroxypropyl methacrylate, vinylpyridine, and 4-vinylimidazole. The leukocyte removal filter according to claim 1, wherein the copolymer forming the coating layer has a weight average molecular weight of 50,000 to 200,000. i) subjecting a nonwoven fabric having an average fiber diameter of 0.5 to 5 占 퐉 to a plasma or corona discharge treatment to form a microporous fiber layer;
ii) forming a nanofiber layer having an average fiber diameter of 50 to 1,000 nm by electrospinning on the microporous fiber layer in the step i); And
iii) a coating layer of a polyethylene glycol homopolymer coating layer, a polypropylene glycol homopolymer coating layer, or a copolymer coating layer of a polyether glycol or a polypropylene glycol derivative having a double bond at the terminal and an acrylic or methacrylic monomer on the nanofiber layer of the step ii) And removing the leukocyte-removing filter.