JP6705685B2 - Biological fluid treatment filter and filter device - Google Patents

Description

The present invention relates to a biological fluid treatment filter and filter device containing red blood cells and plasma.

In the field of blood transfusion, leukocyte-removing transfusion in which blood is transfused after removing contaminated leukocytes contained in blood products has become common. This includes side effects such as headache, nausea, and chills associated with blood transfusion, and allergic sensitization that seriously affects recipients, posttransfusion graft-versus-host disease (GVHD), and serious side effects such as viral infection. This is because it has been clarified that it is caused mainly by leukocytes mixed in blood products used for blood transfusion.

As for platelets, it was revealed that anti-platelet antibodies are produced in the body of a transfused person, and in order to suppress the production of anti-platelet antibodies, the demand for blood products free of platelets is increasing. is there.

Also in the field of blood purification, the production of cytokines and physiologically active substances such as alarmin is suppressed by removing leukocytes from patients with inflammatory conditions such as sepsis and systemic inflammatory response syndrome (SIRS) by using an extracorporeal circulation filter device. As a result, leukocyte depletion therapy for treating inflammatory conditions is drawing attention.

Filters for treating biologically derived liquids containing red blood cells such as blood and blood preparations are required to have the ability to remove the target one and not to have adverse effects such as hemolysis on red blood cells.

Regarding a filter for removing white blood cells and platelets from a biologically derived liquid containing red blood cells, Patent Document 1 discloses that a carrier surface is coated with a polymer containing an alkylsulfonic acid of a quaternary amine to cationize and hydrophilize the surface. Discloses a filter and a filter device capable of efficiently interacting with both white blood cells and platelets to efficiently remove both.

Further, Patent Document 2 discloses that a polymer containing a basic monomer such as methyl (meth)acrylate and dimethylaminoethyl acrylate and a protic neutral hydrophilic monomer such as 2-hydroxyethyl (meth)acrylate is provided on a carrier surface. Disclosed are a filter and a filter device that remove white blood cells and platelets by coating and have excellent blood priming properties. Patent Document 3 discloses a technique in which leukocyte removal performance is improved by a surface in which both a basic functional group and an acidic functional group are introduced by separate monomers.

Patent Document 4 discloses a ternary polymer in which a nonionic monomer for mitigating the influence of a cationic monomer and preventing hemolysis is added as a polymer composition in order to suppress damage to red blood cells due to the polymer being cationic. By coating the surface of the carrier with the method, both the leukocyte removal performance and the hemolytic prevention property are disclosed.

According to the same idea, Patent Document 5 says that the surface of a carrier is coated with a ternary polymer in which a monomer having an acidic functional group in a side chain is added as a polymer composition, thereby achieving both leukocyte-removing ability and hemolytic prevention ability. The technology is disclosed.

Patent Document 6 discloses that by introducing a functional group having a zwitterion and a functional group having a cation such as a quaternary amine permanently on the surface of a substance that comes into contact with blood, blood cells and plasma in blood can be obtained. Disclosed is a technique of delaying the protein surface attachment and improving the blood compatibility of the material by coating the surface with heparin contained in blood as a coagulant.

Non-Patent Document 1 reports that when the surface of hydrophilic polyhydroxyethyl methacrylate (PHEMA) is precoated with serum, a marked increase in the amount of adhesion of leukocytes was observed.

JP-A-2000-197814 Japanese Patent No. 4252449 JP-A-8-281100 International Publication No. 2006/016163 International Publication No. 2006/016166 Patent No. 4295359

Mitsuo Okano et al., "Development of Materials for Immunoengineering: Adsorption of Antibody on Polymer Surface, Control of Orientation and Its Application", Artificial Organ Volume 10, No. 1, 1981.

An object of the present invention is to provide a biological fluid treatment filter and a filter device capable of treating a biological fluid containing red blood cells and plasma without adversely affecting red blood cells.

In the technology disclosed in Patent Document 1, a polymer containing a monomer unit containing an alkyl sulfonate of a quaternary amine is used, and in the technology disclosed in Patent Document 2, a monomer containing a basic nitrogen-containing functional group. By coating the surface of the carrier with a polymer containing a unit and a monomer unit containing a protic neutral hydrophilic group, it is attempted to improve the hydrophilicity and improve the wettability to the filter, and the leukocyte removal performance and the platelet removal performance. We aim to improve. However, when the present inventors treated blood with the filters described in Patent Documents 1 and 2, there were problems of red blood cell adhesion to the filter and red blood cell hemolysis.

Patent Document 3 discloses a technique for improving leukocyte removal performance by a surface into which both a basic functional group and an acidic functional group are introduced by separate monomers, but does not mention hemolytic properties of red blood cells. In Patent Document 3, it is mentioned that a monomer that is an amphoteric chemical species is used as a method for introducing a basic functional group and an acidic functional group. However, when an amphoteric chemical species is used, a basic functional group is used. It is not disclosed whether the leukocyte removal performance can be improved as in the case where the group and the acidic functional group are introduced by separate monomers. In this respect, when the present inventors evaluated the surface introduced with ethyl betaine methacrylate having both a basic functional group and an acidic functional group, no improvement in leukocyte removal performance was observed.

In the technique disclosed in Patent Document 4, MMA (methyl methacrylate) or DEGMEMA (diethylene glycol methoxyethyl methacrylate) or the like is used as a third component of the polymer to reduce the anionic property of the basic nitrogen-containing functional group. By coating the surface of the carrier with a ternary polymer containing a monomer, attempts have been made to achieve both leukocyte-removing ability and hemolysis-preventing ability, but the prevention of hemolysis was insufficient.

Also in the technique disclosed in Patent Document 5, the white blood cells are coated with a ternary polymer to which a monomer having a cationic functional group is added as a third component in the same manner as in Patent Document 4, by coating the carrier surface. Attempts have been made to achieve both removal performance and hemolytic prevention, but prevention of hemolysis was also insufficient here.

Patent Document 6 discloses a biocompatible polymer into which a zwitterionic group and a quaternary amine having a cation permanently are introduced at the same time. There is no mention of the hemolytic properties of red blood cells. In this respect, the present inventors evaluated the surface coated with a polymer containing a functional group containing a zwitterion and diethyl ammonium methacrylate having a quaternary amine, and showed that the prevention of hemolysis was insufficient. Met.

As a result of intensive studies to achieve the above object, the present inventors carry a polymer having a hydroxyalkyl (meth)acrylate, a functional group containing a zwitterion, and a basic nitrogen-containing functional group. The present invention has been completed by finding that a biological fluid containing red blood cells and plasma can be treated without adversely affecting red blood cells by using a filter having a carrier.

That is, an aspect of the present invention is a filter for treating a biological fluid containing red blood cells and plasma, which has a carrier and a polymer supported on the carrier, and the polymer is a hydroxyalkyl (meth)acrylate. has a functional group containing a zwitterionic, and a basic nitrogen-containing functional group, a basic nitrogen-containing functional groups, -NH _2, -NHR ₁ or _{-NR 2 R 3 (R 1,} R 2, R ₃ is a biological-derived liquid treatment filter, which is an alkyl group having 1 to ₃ carbon atoms.

In the above biological liquid treatment filter, the polymer may be supported in an amount of 1.0 mg or more and 32.5 mg or less per 1 g of the carrier. In the above biological solution treatment filter, the zwitterion-containing functional group may be derived from at least one selected from the group consisting of carbobetaine, sulfobetaine, and phosphobetaine.

In the above-mentioned biological liquid treatment filter, a hydroxyalkyl (meth)acrylate (l), a monomer unit (m) having a basic nitrogen-containing functional group, and a monomer unit (n) having a zwitterionic functional group. , The molar ratio of the monomer units constituting the polymer is 100 as a whole,
l+m+n=100,
0<l,m,n<100
May be satisfied.

In the above-mentioned biological liquid treatment filter, a hydroxyalkyl (meth)acrylate (l), a monomer unit (m) having a basic nitrogen-containing functional group, and a monomer unit (n) having a zwitterionic functional group. , May have a molar ratio of 1/m/n=40.0 to 97.0/1.5 to 32.5/1.5 to 32.5.

In the above-mentioned biological fluid treatment filter, the monomer unit having a basic nitrogen-containing functional group in the polymer may be N,N-dialkylaminoalkyl(meth)acrylate.

In the above biological liquid treatment filter, the hydroxyalkyl (meth)acrylate is hydroxyethyl (meth)acrylate, and the N,N-dialkylaminoalkyl (meth)acrylate is N,N-diethylaminoethyl (meth)acrylate. The functional group having a zwitterion may be methyl betaine methacrylate.

In the above biological liquid treatment filter, hydroxyalkyl (meth)acrylate is hydroxypropyl (meth)acrylate, and N,N-dialkylaminoalkyl (meth)acrylate is N,N-diethylaminoethyl (meth)acrylate. The functional group having a zwitterion may be methyl betaine methacrylate.

In the above biological liquid treatment filter, the material of the carrier may be polyethylene terephthalate or polybutylene terephthalate. Alternatively, the carrier may be a non-woven fabric.

Further, an aspect of the present invention is a filter device for treating a biological fluid containing red blood cells and plasma, the housing having an inlet and an outlet for the biological fluid, and the above biological fluid treatment housed in the housing. A filter device including a filter.

According to the present invention, it is possible to provide a biological fluid treatment filter and a filter device capable of treating a biological fluid containing red blood cells and plasma without adversely affecting red blood cells.

It is an exploded perspective view showing a living body origin fluid treatment filter device concerning one embodiment. It is a schematic diagram which shows the blood product filtration system which concerns on one Embodiment. 4 is a table showing the monomer composition, coating amount, carrier material, and evaluation result in the examples. 5 is a table showing the monomer composition, coating amount, carrier material, and evaluation result in Comparative Examples and Reference Examples.

Hereinafter, a preferred embodiment of the present invention (hereinafter referred to as "the present embodiment") will be described in detail. In addition, the present embodiment described below exemplifies an apparatus and a method for embodying the technical idea of the present invention, and the technical idea of the present invention specifies a combination of constituent members and the like as follows. Not something to do. The technical idea of the present invention can be modified in various ways within the scope of the claims.

A filter for treating a biological fluid containing erythrocytes and plasma according to the present embodiment includes a carrier and a polymer supported on the carrier, and the polymer is a hydroxyalkyl (meth) which is a monomer unit having a nonionic group. ) An acrylate, a functional group containing a zwitterion, and a basic nitrogen-containing functional group. Additionally, basic nitrogen Motokan functional group is, -NH _2, -NHR ₁ or _{-NR 2 R 3 (R 1,} R 2, R 3 is an alkyl group having 1 to 3 carbon atoms) is.

A biological fluid containing red blood cells and plasma includes all fluids derived from a living body that contain plasma among those in which red blood cells are dispersed, and specifically, blood and blood products prepared from blood. Is included. The polymer is supported by being coated on a carrier, for example. Hereinafter, the polymer supported on the carrier is also referred to as “coating polymer”. However, the method of supporting the polymer on the carrier is not limited to this.

(Coating polymer)
Polymer contained in the filter according to the present embodiment, a hydroxyalkyl (meth) acrylate, a functional group containing a _zwitterion, -NH 2, -NHR ₁ or _{-NR 2 R 3 (R 1,} R 2, R ₃ is a basic nitrogen-containing functional group which is an alkyl group having 1 to ₃ carbon atoms).

The polymer is a copolymer of at least hydroxyalkyl (meth)acrylate, a monomer having a functional group containing a zwitterion, and a monomer having a basic nitrogen-containing functional group. The copolymer may be a random copolymer or a block copolymer.

Examples of the functional group containing a zwitterion include functional groups represented by the following general formulas (1), (2) and (3).

The general formula (1) represents carbobetaine. In the general formula (1), R ₁ is an alkyl group having 1 or more carbon atoms.

The general formula (2) represents sulfobetaine. In the general formula (2), R ₂ is an alkyl group having 1 or more carbon atoms.

Formula (3) represents phosphobetaine. In the general formula (3), R ₃ is an alkyl group having 1 or more carbon atoms.

Among the zwitterion-containing functional groups represented by the general formulas (1), (2), and (3), the economically preferable one is methyl betaine methacrylate represented by the following general formula (4). Is a functional group derived from.

The basic nitrogen-containing functional group can be defined as a functional group containing a nitrogen atom having an ability to accept a hydrogen ion from the definition of Bronsted-Lowry acid-base. That, -NH ₂ having an unshared electron pair for receiving a hydrogen _{ion, -NHR 1, -NR 2 R 3} (R 1, R 2, R 3 is an alkyl group having 1 to 3 carbon atoms) represented by Is an amino group.

In general, living cells such as white blood cells have a negative charge, so that the non-shared electron pair of the basic nitrogen-containing functional group in the filter has a cationic property after receiving a hydrogen ion, and thus interacts with white blood cells, As a result, the filter is believed to be able to remove white blood cells. However, if there is a functional group that exhibits a cation regardless of the environment such as the pH of the solution like the quaternary amine, the cationicity becomes too strong and the possibility of hemolyzing red blood cells increases. Therefore as the functional groups that impart cationic, -NH _2, -NHR _1, the basic nitrogen-containing functional group represented by -NR ₂ R ₃ it is used.

A typical example of the compound having a basic nitrogen-containing functional group is N,N-dialkylaminoalkyl(meth)acrylate. Among them, N,N-diethylaminoethyl(meth)acrylate is taken into consideration in view of easy availability and economy. ) Acrylate is preferred.

Without being bound by the theory below, by introducing a positive charge and a negative charge to the carrier by a functional group containing a zwitterion in which the positive charge and the negative charge are present in the same side chain, a specific charge is Since it is not localized on the filter surface, it is considered that the interaction between erythrocytes can be relaxed and hemolysis can be reduced. Further, by using a polymer constitutional unit containing a functional group containing a zwitterion and a basic nitrogen-containing functional group, the positive nitrogen atoms introduced by the basic nitrogen-containing functional group improve the leukocyte removal performance while being combined. It is considered that the functional groups containing zwitterions can alleviate the interaction between erythrocytes and exert the hemolytic prevention performance. Furthermore, it is considered that the leukocyte removal performance is improved by the polymer containing hydroxyalkyl (meth)acrylate.

From the viewpoint of exhibiting higher anti-hemolytic property, the proportion of the monomer units having a zwitterion-containing functional group is preferably 1.5% or more in terms of molar ratio with respect to the total monomer units of the coating polymer. The ratio of the monomer unit having a zwitterion-containing functional group to all the monomer units can be calculated by extracting the polymer in a soluble solvent and combining nuclear magnetic resonance (NMR) measurement and amino group content measurement. ..

In the case of a filter for leukocyte removal and/or platelet removal, the coating polymer is a hydroxyalkyl (meth)acrylate, a monomer unit having a basic nitrogen-containing functional group, and a monomer unit having a zwitterionic functional group in the side chain. It is preferred that the following units are included, and that monomer units other than these are not included. In other words, with the total molar ratio of the monomer units constituting the coating polymer being 100, the hydroxyalkyl (meth)acrylate (l) contained in the coating polymer and the monomer unit (m) having a basic nitrogen-containing functional group. The molar ratio of the monomer unit (n) having a functional group containing a zwitterion in the side chain is preferably l+m+n=100,0<l,m,n<100. When the molar ratio is within the above range, excellent leukocyte removal performance and platelet removal performance can be realized while suppressing damage to red blood cells such as hemolysis. When the molar ratio of the monomer unit having a zwitterion-containing functional group is higher than 32.5% and the molar ratio of the monomer unit having a basic nitrogen-containing functional group is lower than 1.5%, there is a problem in hemolysis of red blood cells. However, the leukocyte removal performance and the platelet removal performance tend to decrease. From the viewpoint of further exhibiting the effect of removing leukocytes and/or platelets while ensuring the effect of preventing hemolysis, hydroxyalkyl (meth)acrylate contained in the coating polymer and a monomer unit having a basic nitrogen-containing functional group , And a monomer unit having a functional group containing a zwitterion, for example, in a molar ratio of 40.0 to 97.0/1.5 to 32.5/1.5 to 32.5, and preferably 40. 0-95.0/2.5-30.0/2.5-30.0, more preferably 50.0-95.0/2.5-30.0/2.5-30.0. And more preferably 60.0 to 95.0/2.5 to 30.0/2.5 to 30.0.

The procedure for measuring and calculating the molar ratio of the hydroxyalkyl (meth)acrylate contained in the coating polymer, the monomer unit having a basic nitrogen-containing functional group and the monomer unit having a functional group containing a zwitterion is described in Hydroxyalkyl. (Meth)acrylate, N,N-dialkylaminoalkyl(meth)acrylate, and methyl betaine methacrylate will be described as examples. First, the coating polymer is dissolved in an appropriate solvent such as dimethyl sulfoxide, and then proton nuclear magnetic resonance ( ¹ H-NMR) measurement is performed. From the obtained ¹ H-NMR, the total amount of monomer units is calculated from the peaks (peaks at 0.3-1.3 ppm and peaks at 1.3-2.2 ppm) belonging to H contained in all monomer units. .. Next, a peak (2.6 ppm) assigned to H contained in N,N-dialkylaminoalkyl(meth)acrylate and a peak (3 assigned to H contained in a monomer unit having a zwitterion as a side chain). Each amount is obtained from 0.7 ppm). Furthermore, the remainder obtained by subtracting the amounts of the two monomer units previously obtained from the total amount of the monomer units is used as the amount of hydroxyalkyl (meth)acrylate, and hydroxyalkyl (meth)acrylate and N,N-dialkylaminoalkyl are obtained. The abundance ratio of (meth)acrylate and methyl betaine methacrylate is calculated.

(Raw material of polymer)
Examples of hydroxyalkyl (meth)acrylates include hydroxyethyl (meth)acrylate and hydroxypropyl (meth)acrylate.

In order to synthesize a polymer having a functional group containing a zwitterion represented by the above formulas (1) to (3), compounds represented by the following general formulas (5), (6) and (7) are used. It is preferable to synthesize the polymer by using

In the general formula (5), R ₅ and R ₆ are H or an alkyl group having 1 to 3 carbon atoms, and R ₄ and R ₇ are CH ₂ —CH ₂ , CH ₂ —CHR _a , and CHR _a —CH. ₂ , CHR _a —CHR _b , CHR _a —CR _b R _c , CR _a R _b —CHR _c , CRaR _b —CR _c R _d , and (CH ₂ ) _g (g=integer of 2 to 6). And R _a , R _b , R _c , and R _d are alkyl groups having 1 to 3 carbon atoms.

In the general formula (6), R ₉ and R ₁₁ are H or an alkyl group having 1 to 3 carbon atoms, and R ₈ and R ₁₀ are CH ₂ —CH ₂ , CH ₂ —CHR _a , and CHR _a —CH. ₂ , CHR _a —CHR _b , CHR _a —CR _b R _c , CR _a R _b —CHR _c , CR _a R _b —CR _c R _d , and (CH ₂ ) _g (g=integer of 2 to 6) Any one of R _a , R _b , R _c , and R _d is an alkyl group having 1 to 3 carbon atoms.

In the general formula (7), R ₁₄ , R ₁₅ , and R ₁₆ are H or an alkyl group having 1 to 3 carbon atoms, and R ₁₂ and R ₁₃ are CH ₂ —CH ₂ , CH ₂ —CHR _a , and CHR. _{a -CH 2, CHR a -CHR b} , CHR a -CR b R c, CR a R b -CHR c, CR a R b -CR c R d, and _{(CH 2) g (g =} 2~6 of R _a , R _b , R _c , and R _d are alkyl groups having 1 to 3 carbon atoms.

Examples of the monomer for introducing the basic nitrogen-containing functional group into the polymer include compounds represented by the following general formula (8).

In the general formula (9), R ₁₉ , R ₂₁ , and R ₂₂ are each H, an alkyl group having 1 to 3 carbon atoms, a phenyl group, or a derivative thereof, and R ₂₀ is CH ₂ -CH. _{2, CH 2 -CHR a, CHR} a -CH 2, CHR a -CHR b, CHR a -CR b R c, CR a R b -CHR c, CR a R b -CR c R d and, (CH ₂ ) _E (e represents an integer of 2 to 6), and R _a , R _b , R _c , and R _d are alkyl groups having 1 to 3 carbon atoms.

A typical example of the monomer represented by the general formula (9) is N,N-dialkylaminoalkyl(meth)acrylate, and among them, N,N-diethylaminoethyl(meth)acrylate is taken into consideration in view of easy availability and economy. Acrylate is preferred.

(Carrier)
The material of the carrier is not particularly limited as long as it is used as a filter for treating a biological fluid containing red blood cells, but a thermoplastic polymer is preferable. When the material of the carrier is a thermoplastic polymer, it is possible to melt and perform spinning. Therefore, for example, by a melt blow method, a flash spinning method or a papermaking method, a nonwoven fabric, paper, woven fabric or mesh is formed. be able to. From the viewpoint of the degree of freedom of such a form, the material of the carrier is more preferably polyethylene terephthalate or polybutylene terephthalate.

Examples of the form of the carrier include non-woven fabric, paper, woven fabric, mesh, particles, and hollow fiber, and non-woven fabric is preferred. The non-woven fabric means a cloth-like one in which an aggregate of fibers or threads is chemically, thermally or mechanically bonded to each other regardless of the knitting or weaving.

When the carrier is a non-woven fabric or a woven fabric, the average fiber diameter thereof can be 0.3 μm to 10.0 μm, preferably 0.3 μm to 3.0 μm, and 0.5 μm to 1.8 μm. Is more preferable. When the average fiber diameter is 0.3 μm or more, the pressure loss when filtering blood is appropriate. Further, when it is 10.0 μm or less, the leukocyte removal performance and the platelet removal performance tend to be more remarkably exhibited, and therefore it is suitable for these applications.

Here, the average fiber diameter is an average diameter measured by a photograph obtained by sampling a part of a non-woven fabric or a woven fabric constituting a filter and observing it with an electron microscope.

(filter)
In the filter, the coating polymer is supported on the carrier, and the supported amount (also referred to as “coating amount”) is 1.0 mg or more and 32.5 mg or less, preferably 2.0 mg or more and 32.0 mg or less per 1 g of the carrier. , And more preferably 2.5 mg or more and 31.5 mg or less. When the coating amount is 1.0 mg or more per 1 g of the carrier, the filter has high wettability with a liquid derived from a living body including red blood cells and the flowability of the filter is good. hard. Further, from the viewpoint of preventing elution of the polymer into a biological fluid containing red blood cells and hemolysis, the coating amount is preferably 32.5 mg or less per 1 g of the carrier. Here, the term “support” means that the coating polymer is bound or adsorbed to the carrier, for example, chemically, physically or electrically.

The coating amount is calculated by the following procedure. The carrier before supporting the coating polymer is dried in a dryer set at 60° C. for 1 hour, and then left in a desiccator for 1 hour or more, and then the weight (Ag) is measured. Similarly, the carrier (filter) supporting the coating polymer is dried in a dryer at 60° C. for 1 hour and then left in a desiccator for 1 hour or more, and then the weight (Bg) is measured. The coating amount is calculated by the following calculation formula.
Coating amount (mg/g carrier)=(B−A)×1000/A

The filter according to the present embodiment, since a biological fluid containing red blood cells can be processed without adversely affecting red blood cells, a filter for a white blood cell and/or platelet removal filter device for blood products containing red blood cells, It is preferably used as a filter for an extracorporeal circulation treatment filter device for removing activated leukocytes from patient blood. Examples of blood products containing red blood cells include whole blood products and red blood cell products. In view of the above effects, the blood product containing red blood cells is preferably a transfusion product.

Diseases to be treated by the filter device for extracorporeal circulation treatment include sepsis, systemic inflammatory syndrome (SIRS), rheumatism, and ulcerative colitis, which are caused by leukocyte release of excessive physiologically active substances. If applicable, it is applicable.

In one embodiment of the present invention, there are provided leukocyte and platelet removal filters and filter devices for blood products that include red blood cells.

(Method of manufacturing the filter)
The filter can be obtained by supporting the above-mentioned coating polymer on the above-mentioned carrier. The carrying method, specifically, the coating method is not particularly limited, but for example, a coating method, a spray method, or a dipping method can be used.

The dipping method is to immerse the carrier in a coating solution prepared by dissolving the above-mentioned coating polymer in a suitable organic solvent such as alcohol, chloroform, acetone, tetrahydrofuran, or dimethylformamide, removing the excess solution, and then air drying. It can be carried out by drying by an appropriate means. As a drying method, there are a method of air-drying in a dry gas, a method of drying at room temperature or while heating in a reduced pressure atmosphere, and the like.

The coating method and the spray method can be carried out by coating or spraying the above-mentioned coating liquid on a carrier and then drying it as described above.

(Biological liquid treatment filter device)
FIG. 1 is an exploded perspective view showing a biological fluid treatment filter device according to an embodiment. The biological fluid treatment filter device 100 shown in FIG. 1 includes a resin jig 10 having an inlet 1 for blood products containing red blood cells and a resin jig 11 having an outlet 2 for blood products. A filter unit 21 in which nine filters 20 according to the present embodiment are stacked is included in a housing formed by 10 and a resin jig 11. The number of filters 20 in the filter unit 21 is not particularly limited and may be set appropriately. Further, the resin jig 10 and the resin jig 11 may be joined by fusion, adhesion with an adhesive, or the like.

FIG. 2 is a schematic diagram showing a biological fluid treatment system according to one embodiment. The biological fluid treatment system 200 shown in FIG. 2 includes a syringe pump 110 that stores a biological fluid 210 before treatment, a biological fluid treatment filter device 100, and a container 130 that stores a biological fluid after treatment 220. The syringe pump 110 and the biological fluid treatment filter device 100 are connected by a tube 140. In addition, the biological liquid treatment filter device 100 and the container 130 are connected by a tube 150.

The unprocessed biological fluid 210 transferred from the syringe pump 110 through the tube 140 is processed by the biological fluid processing filter device 100 to remove leukocytes and platelets. The pressure at which the unprocessed living body-derived liquid 210 is filtered by the living body-derived liquid treatment filter device 100 is measured by the pressure gauge 120. Since the biological fluid treatment filter device 100 includes the filter according to this embodiment described above, hemolysis of erythrocytes or the like does not occur in the biological fluid 220 after the treatment. After the treatment, the biological fluid 220 is contained in the container 130. For example, when the biological fluid is a blood product, it is used as a blood product for transfusion.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples.

[Example 1]
(Synthesis of coating polymer and measurement of molar ratio)
A copolymer of hydroxyethyl (meth)acrylate (HEMA), N,N-diethylaminoethyl (meth)acrylate (DEAEMA), and methyl betaine methacrylate (CMB) was synthesized by ordinary solution polymerization. The polymerization conditions were as follows: Polymerization reaction was carried out at 60° C. for 8 hours in an ethanol solution having a monomer concentration of 1 mol/L in the presence of 0.0025 mol/L of azoisobutyronitrile (AIBN) as an initiator. The obtained polymer polymerization liquid was added dropwise to water to collect the precipitated polymer. The recovered polymer was pulverized and then dried under reduced pressure for 24 hours to obtain a coating polymer.

The molar ratio of the hydroxyethyl (meth)acrylate monomer, the N,N-diethylaminoethyl (meth)acrylate monomer, and the methyl betaine methacrylate in the coating polymer is such that after the obtained coating polymer is dissolved in dimethyl sulfoxide, As a result of calculation by performing ¹ H-NMR measurement, the molar ratio of hydroxyethyl (meth)acrylate, N,N-diethylaminoethyl (meth)acrylate, and methyl betaine methacrylate was 70.0/10. It was 0/20.0.

(Preparation of coating liquid)
After the above coating polymer was added to 90 W/W% ethyl alcohol, it was stirred for 12 hours to prepare a coating liquid having a coating polymer concentration of 0.56% by weight.

(Coating method)
A non-woven fabric made of polyethylene terephthalate (PET) fiber having an average fiber diameter of 1.2 μm (40 g/m ² basis weight, “Micro Web” manufactured by Asahi Kasei Fibers Corp.) was cut into a size of 210 mm×150 mm, and the coating liquid was put into the metal. It was dipped in a bat for 20 seconds. After dropping the excess coating liquid, it was air dried at room temperature.

(Measurement of coating amount)
At the time of the coating, the nonwoven fabric cut out to 210 mm×150 mm was dried with a hot air dryer set at 60° C. for 1 hour, and the nonwoven fabric weight (Ag) measured, and the nonwoven fabric coated by the above method was similarly set at 60° C. The coated amount was obtained from the following calculation formula using the weight (Bg) of the coated non-woven fabric measured after drying for 1 hour or more with the hot air dryer.
Coating amount=(weight B−weight A)×1000/weight A
As a result, the coating amount per 1 g of the carrier was 20.0 mg.

(Leukocyte removal performance, platelet removal performance and hemolysis test method)
The coated non-woven fabric was punched with a punching blade having a diameter of 20 mm, nine sheets were stacked and sandwiched between resin jigs 10 and 11 having an inlet 1 and an outlet 2 for the blood product as shown in FIG. A blood evaluation test (leukocyte removal performance, platelet removal performance and hemolysis test) was performed on this removal filter device using a filtration system as shown in FIG. The blood product used in the blood evaluation test is preserved human whole blood supplemented with CPD. Blood collected from a donor and stored at room temperature for 24 hours was used. The flow rate of the blood product in the test was set to 40 mL/hour.

(Leukocyte removal performance)
As a result of calculating the leukocyte removal performance according to the following calculation formula, the leukocyte removal performance was 4.7.
Leukocyte removal capacity=−log [(white blood cell concentration in blood product after filtration)/(white blood cell concentration in blood product before filtration)]

The white blood cell concentration in the blood product before and after filtration was measured using a leukocyte count kit "LeucoCOUNT" manufactured by Becton Dickinson Company (BD) and a flow cytometer FACS CantoII manufactured by BD.

(Platelet removal performance)
As a result of calculating the platelet removal performance according to the following formula, the platelet removal performance was 99%.
Platelet removal performance (%)=[(platelet concentration in blood product before filtration-platelet concentration in blood product after filtration)/platelet concentration in blood product before filtration]×100

The platelet concentration in the blood product before and after filtration was measured using a multi-item automatic blood cell counter (K-4500 manufactured by Japan Sysmex).

(Hemolytic test method)
The blood product before and after filtration was centrifuged at 3000 revolutions/min (1700×g) for 15 minutes, and then the coloring of the supernatant was observed and compared before and after filtration against a white paper background, and evaluated according to the following criteria. As a result, (-) no hemolysis was observed.
(I) The blood product supernatant after filtration has a red color that is distinctly darker than that of the blood product supernatant before filtration. (+) There is hemolysis. (ii) The blood product supernatant after filtration is compared with the supernatant of the blood product before filtration. Red blood cells with a reddish color are found in the supernatant of the blood product (±), and (iii) Red blood cells are not colored in the supernatant of the blood product after filtration compared to the blood product before filtration. (-) No hemolysis

[Example 2]
The same filter as in Example 1 was used except that the coating amount of the coating polymer was 2.5 mg per 1 g of the carrier. Leukocyte removal performance, platelet removal performance, and hemolysis evaluation were carried out in the same manner as in Example 1, and as a result, they were 4.6, 99%, and (−) no hemolysis, respectively.

[Example 3]
A filter similar to that in Example 1 was used, except that the coating amount of the coating polymer was 30.0 mg per 1 g of the carrier. Leukocyte removal performance, platelet removal performance and hemolysis evaluation were carried out in the same manner as in Example 1, and the results were 4.6, 99%, and (−) no hemolysis, respectively.

[Example 4]
Except that the composition of the coating polymer is HEMA/DEAEMA/CMB=95.0/2.5/2.5 (molar ratio), and the coating amount of the coating polymer is 1.0 mg per 1 g of the carrier. A filter similar to Example 1 was used. Leukocyte removal performance, platelet removal performance and hemolysis evaluation were carried out in the same manner as in Example 1, and the results were 4.6, 99%, and (−) no hemolysis, respectively.

[Example 5]
Except that the composition of the coating polymer was HEMA/DEAEMA/CMB=67.5/30.0/2.5 (molar ratio), and the coating amount of the coating polymer was 30.0 mg per 1 g of the carrier. A filter similar to Example 1 was used. Leukocyte removal performance, platelet removal performance and hemolysis evaluation were carried out in the same manner as in Example 1, and the results were 4.7, 99% and (−) no hemolysis, respectively.

[Example 6]
Except that the composition of the coating polymer was HEMA/DEAEMA/CMB=67.5/2.5/30.0 (molar ratio), and the coating amount of the coating polymer was 1.0 mg per 1 g of the carrier. A filter similar to Example 1 was used. The leukocyte removal performance, platelet removal performance and hemolysis evaluation were carried out in the same manner as in Example 1, and the results were 4.5, 99% and (−) no hemolysis, respectively.

[Example 7]
The composition of the coating polymer is hydroxypropylmethacrylic acid (HPMA)/DEAEMA/CMB=67.5/30.0/2.5 (molar ratio), and the coating amount of the coating polymer is 30.0 mg/g carrier. A filter similar to that of Example 1 was used except that it was present. Leukocyte removal performance, platelet removal performance and hemolysis evaluation were carried out in the same manner as in Example 1, and the results were 4.7, 99% and (−) no hemolysis, respectively.

[Example 8]
Except that the composition of the coating polymer is HPMA/DEAEMA/CMB=95.0/2.5/2.5 (molar ratio), and the coating amount of the coating polymer is 1.0 mg per 1 g of the carrier. A filter similar to Example 1 was used. The leukocyte removal performance, platelet removal performance and hemolysis evaluation were carried out in the same manner as in Example 1, and the results were 4.5, 99% and (−) no hemolysis, respectively.

[Example 9]
The same filter as in Example 1 was used except that the material of the nonwoven fabric used was polybutylene terephthalate (PBT). Leukocyte removal performance, platelet removal performance and hemolysis evaluation were carried out in the same manner as in Example 1, and as a result, 4.7%, 99% and (−) no hemolysis were obtained, respectively.

[Comparative Example 1]
Same as Example 1 except that the composition of the coating polymer is HEMA/DEAEMA=70.0/30.0 (molar ratio), and the coating amount of the coating polymer is 5.0 mg per 1 g of the carrier. A filter was used. Leukocyte removal performance, platelet removal performance and hemolysis evaluation were carried out in the same manner as in Example 1, and the results were 4.0, 99% and (+) hemolysis, respectively.

[Comparative example 2]
A filter similar to that in Example 1 was used, except that the composition of the coating polymer was HEMA/CMB=85.0/15.0 (molar ratio). Leukocyte removal performance, platelet removal performance, and hemolysis evaluation were carried out in the same manner as in Example 1, and as a result, they were 2.8, 60%, and (−) no hemolysis, respectively.

[Comparative Example 3]
A filter similar to that in Example 1 was used, except that the composition of the coating polymer was HEMA/DEAEMA/CMB=30.0/35.0/35.0 (molar ratio). Leukocyte removal performance, platelet removal performance, and hemolysis evaluation were carried out in the same manner as in Example 1, and the results were 3.8, 99%, and (±) hemolysis, respectively.

[Comparative Example 4]
A filter similar to that in Example 1 was used, except that the coating amount of the coating polymer was 35.0 mg per 1 g of the carrier. The leukocyte removal performance, platelet removal performance and hemolysis evaluation were carried out in the same manner as in Example 1, and as a result, 4.7%, 99%, and (+) hemolysis were found, respectively.

[Comparative Example 5]
Filter similar to Example 1, except that the composition of the coating polymer is 2-methoxyethyl (meth)acrylate (MEMA)/DEAEMA/CMB=70.0/10.0/20.0 (molar ratio). It was used. Leukocyte removal performance, platelet removal performance and hemolysis evaluation were carried out in the same manner as in Example 1, and the results were 4.4, 99% and (−) no hemolysis, respectively.

[Comparative Example 6]
The composition of the coating polymer is HEMA/DEAEMA/AH (acrylic acid; cationic monomer)=60.0/30.0/10.0 (molar ratio), and the coating amount of the coating polymer is 20/g of the carrier. A filter similar to that of Example 1 was used except that the amount was 0 mg. The leukocyte removal performance, platelet removal performance and hemolysis evaluation were carried out in the same manner as in Example 1, and the results were 3.7, 90%, and (+) hemolysis, respectively.

[Comparative Example 7]
Same as Example 1 except that the composition of the coating polymer was HEMA/DEAEMA/DEGMEMA (diethylene glycol methoxyethyl methacrylic acid; nonionic monomer)=60.0/30.0/10.0 (molar ratio). I used a filter. Leukocyte removal performance, platelet removal performance, and hemolysis evaluation were carried out in the same manner as in Example 1, and as a result, they were 3.7, 99%, and (+) hemolysis, respectively.

[Reference Example 1]
Currently, the filter is taken out from the leukocyte removal filter device (Sepacel manufactured by Asahi Kasei Medical Co., Ltd.), and the leukocyte removal performance, the platelet removal performance and the hemolysis evaluation are carried out in the same manner as in Example 1, and the results are 3.0 and 95%, respectively. And (-) no hemolysis.

The monomer composition, coating amount, carrier material and evaluation results in Examples, Comparative Examples and Reference Examples are also shown in FIGS. 4 and 5.

As a monomer component in the coating polymer, a hydroxyalkyl (meth)acrylate, a monomer having a basic nitrogen-containing functional group, and a monomer having a functional group containing a zwitterion in its side chain are contained, and the composition ratio thereof is controlled. the biological fluid containing red blood cells and plasma by, came in without processing it adversely affect the erythrocytes. Further, in the case of a filter for removing white blood cells and platelets, white blood cells and platelets could be removed with high efficiency.

1... Inlet, 2... Outlet, 10, 11... Resin jig, 20... Filter, 21... Filter unit, 100... Biological fluid treatment filter device, 110... Syringe pump, 130... Container, 140, 150... Tube, Reference numeral 200... Biological fluid treatment system, 210... Pretreatment biological fluid, 220... Posttreatment biological fluid.

Claims (11)

A filter for treating a biological fluid containing erythrocytes and plasma, comprising a carrier and a polymer supported on the carrier, wherein the polymer has a hydroxyalkyl (meth)acrylate and a functional group containing a zwitterion. And a basic nitrogen-containing functional group, wherein the basic nitrogen-containing functional group is —NH ₂ , —NHR ₁ or —NR ₂ R ₃ (R ₁ , R ₂ and R ₃ are each a carbon number of 1 to 1). alkyl group) der of 3 is,
The hydroxyalkyl (meth)acrylate (l), the monomer unit (m) having the basic nitrogen-containing functional group, and the monomer unit (n) having the functional group containing the zwitterion have a molar ratio of: With the total molar ratio of the monomer units constituting the polymer being 100,
l+m+n=100,
0<l,m,n<100
Meet the relationship of
Biological fluid treatment filter. The biological fluid treatment filter according to claim 1, wherein the polymer is supported in an amount of 1.0 mg or more and 32.5 mg or less per 1 g of the carrier. The biological fluid treatment filter according to claim 1, wherein the functional group containing a zwitterion is derived from at least one selected from the group consisting of carbobetaine, sulfobetaine, and phosphobetaine. The hydroxyalkyl (meth)acrylate (l), the monomer unit (m) having the basic nitrogen-containing functional group, and the monomer unit (n) having the functional group containing the zwitterion have a molar ratio of: The biological fluid treatment filter according to any one of claims 1 to 3 , wherein 1/m/n=40.0 to 97.0/1.5 to 32.5/1.5 to 32.5. Monomer units having the basic nitrogen-containing functional group in the polymer, N, N-dialkyl amino alkyl (meth) acrylate, biological fluid treatment filter according to any of claims 1-4. The hydroxyalkyl(meth)acrylate is hydroxyethyl(meth)acrylate, the N,N-dialkylaminoalkyl(meth)acrylate is N,N-diethylaminoethyl(meth)acrylate, and the zwitterion is The biological fluid treatment filter according to claim 5 , wherein the functional group possessed is methyl betaine methacrylate. The hydroxyalkyl(meth)acrylate is hydroxypropyl(meth)acrylate, the N,N-dialkylaminoalkyl(meth)acrylate is N,N-diethylaminoethyl(meth)acrylate, and the zwitterion is The biological fluid treatment filter according to claim 5 , wherein the functional group possessed is methyl betaine methacrylate. The material of the carrier is polyethylene terephthalate or polybutylene terephthalate, biological fluid treatment filter according to any of claims 1-7. Wherein the carrier is a non-woven fabric, biological fluid treatment filter according to any of claims 1-8. The biological fluid treatment filter according to any one of claims 1 to 9, which is for removing platelets. It is a filter device which processes the biological origin liquid containing red blood cells and plasma, Comprising: The housing provided with the inlet and outlet of the biological origin liquid, and the biological origin in any one of Claims 1-10 accommodated in the said housing. A filter device comprising a liquid treatment filter.