JP2014100645A - Selective permeable membrane and method of producing the same - Google Patents

Abstract

A selectively permeable membrane having a coating layer made of a phospholipid bilayer membrane and having high separation performance and a method for producing the same are provided.
A method for producing a selective permeable membrane comprising a membrane body having selective permeability and a coating layer made of a phospholipid bilayer membrane formed on the surface of the membrane body, comprising: A method for producing a selective permeable membrane having a vesicle fusion step of contacting a dispersion liquid of a vesicle of a bilayer membrane and the membrane body at a temperature higher than a phase transition temperature of the phospholipid bilayer membrane to form the coating layer The method for producing a selective permeable membrane according to claim 1, wherein the vesicle has an average particle size of 0.5 to 5 µm.
[Selection] Figure 3

Description

  The present invention relates to a method for producing a selective permeable membrane used in the field of water treatment, and more particularly to a method for producing a selective permeable membrane having a coating layer comprising a phospholipid bilayer membrane. The present invention also relates to a selective permeable membrane produced by this method.

  Reverse osmosis (RO) membranes are used as selective permeable membranes in the fields of seawater and brine desalination, wastewater recovery, and the like. Cellulose acetate and polyamide are used as materials for the RO membrane. The cellulose acetate RO membrane is easily hydrolyzed and has a problem that it cannot be washed with alkali when contaminated. The polyamide RO membrane can be washed with an alkali, but has a problem that membrane contamination due to a biological metabolite or the like is likely to occur as compared with a cellulose acetate membrane.

  A phospholipid is a substance that constitutes the cell surface of a living organism, and a technique for coating the surface of a medical instrument or an artificial organ as a biocompatible material is known (Non-patent Document 1). If a biomimetic surface can be constructed with this coating, it is expected that contamination by biological metabolites is unlikely to occur.

  In order to improve the stain resistance of the permselective membrane, it has been studied to apply a phospholipid coating, and it has been reported that the stain resistance is improved (Non-Patent Documents 2 and 3).

  A substance that has a hydrophilic group and a hydrophobic group, represented by phospholipids, and forms lipid bilayers and liposomes (hereinafter sometimes referred to as phospholipids) is adsorbed on the substrate surface. As a method, there is a Langmuir-Blodgett method. For example, there is a method for forming a film by incorporating a membrane protein into a triblock copolymer matrix by the same method (Patent Document 1), and a method for forming an aquaporin sandwich structure with a permeable support layer (Patent Document 2).

  As a method for forming a flat phospholipid bilayer membrane by adsorbing a vesicle composed of a phospholipid bilayer membrane to a flat plate, there is a vesicle fusion method (Non-patent Documents 4 and 5). Non-Patent Document 4 p. 209 in the left column of FIG. FIG. 2 illustrates a phenomenon in which spherical shell vesicles adhere (adsorb) to the surface of a solid substrate and are fused, cleaved, and developed to form a planar lipid film. In lines 13 to 15 of the same column, it is described that vesicles having a diameter of 30 to 200 nm are generally used for film formation by vesicle fusion.

  Non-Patent Document 5 describes a method of forming a phospholipid layer on the surface of an NF membrane by a vesicle fusion method. In order to develop the function as a selective permeable membrane, it is important to control the phospholipid layer formed by the vesicle fusion method. Non-Patent Document 5 describes that a coating layer is formed using fine vesicles obtained by filtering 10 times with a 100 nm (0.1 μm) pore size polycarbonate track etching membrane (MF membrane with controlled pore size). (P.7389, right column, lines 21 to 25 of Non-Patent Document 5).

Patent No. 4444417 Special table 2008-540108

Y. Yao et al., TransMater Res Soc Jpn, Vol. 36 (2011), 573-576 Shigetoshi Ichimura, Jun Sawai, Kanagawa Institute of Technology Research Center for Advanced Technology, Vol.15 (2011), 251-253 Satoshi Hasegawa et al., Proceedings of the Society of Polymer Science, Vol.49 (2000), 3941-3942 Furukawa Kazuki et al., Surface Science Vol.30, No4 (2009), pp.207-218 Y. Kaufman et al., Langmuir, Vol. 26 (2010), 7388-7395

  The above-mentioned P. The right column of 7389 describes that a coating layer is formed by adhering a liquid containing a vesicle having a particle size of 100 nm or less and aquaporin as a channel substance to an NF film.

  As a result of various studies, it has been found that when a vesicle having such a small particle size is used, defects (for example, voids, cracks, etc.) are likely to occur in the formed coating layer. In order to prevent such defects, it is conceivable to increase the film thickness of the coating layer. However, if the film thickness is increased, the permeability is lowered.

  An object of the present invention is to provide a selectively permeable membrane having a coating layer composed of a phospholipid bilayer membrane and excellent in separation performance and a method for producing the same.

  The method for producing a selective permeable membrane of the present invention is the production of a selective permeable membrane having a membrane body having selective permeability and a coating layer comprising a phospholipid bilayer membrane formed on the surface of the membrane body. A vesicle fusion step in which a dispersion of a vesicle of a phospholipid bilayer membrane and the membrane body are contacted at a temperature higher than a phase transition temperature of the phospholipid bilayer membrane to form the coating layer. In the method for producing a selective permeable membrane, the average particle diameter of the vesicle is 0.5 to 5 μm.

  The molecular weight of the amphiphilic molecule constituting the phospholipid bilayer is preferably 200 to 2000.

  The dispersion of vesicles includes fine vesicles having a particle size of less than 0.5 μm.

  The vesicle preferably contains a channel substance.

  As the channel substance, gramicidin, amphotericin B, hemolysin, or aquaporin is preferable.

  The membrane body is preferably an NF membrane.

  The selective permeable membrane of the present invention is produced by the method of the present invention.

  In the present invention, the average particle size of the vesicle is a 50% cumulative value in the particle size distribution obtained from the scattering intensity measured by the dynamic light scattering method. Specifically, in the vesicle particle size distribution obtained by analyzing the scattering intensity detected by the dynamic light scattering method using the Marquad analysis method of the histogram method, 50% accumulation when the frequency is accumulated from the small particle size side. Value. For the measurement of the particle size distribution, for example, an apparatus capable of measuring the particle size distribution by a dynamic light scattering method such as an electrophoretic light scattering photometer ELSZ-2 manufactured by Otsuka Electronics Co., Ltd. can be suitably used. Further, the above analysis processing can be performed by attached software.

  As a result of research, the inventor found that the vesicle size when adsorbing phospholipid vesicles to a selective permeation membrane (NF membrane, etc.) as a base material by the vesicle fusion method affects the characteristics of the phospholipid layer, It was found to affect the performance of the incorporated coating layer.

  When the coating layer is formed using only vesicles having a small particle diameter as in Non-Patent Document 5 described above, defects tend to occur in the coating layer, and it is necessary to form a thick adsorption layer in order to suppress the generation of defects. It will occur. Such a thick film is a major obstacle to drawing out the channel performance of the channel material. However, when a vesicle having an average particle size of 0.5 to 5 μm is used, the surface of the base material covered by one vesicle becomes wider and the small vesicle fills the gap. Thereby, a defect-free phospholipid bilayer can be formed without increasing the thickness of the adsorption layer.

  According to the present invention, a coating layer composed of a phospholipid bilayer membrane having a hydrophilic group and a hydrophobic group is formed on the surface of the NF membrane. Preferably, a channel material is contained in the coating layer, thereby providing a stable permselective membrane having high contamination resistance and separation performance.

  In the present invention, when the vesicle is adsorbed to form a coating layer, it is preferably adsorbed at a temperature 5 to 40 ° C. higher than the phase transition temperature of the phospholipid in order to increase the fluidity of the vesicle.

  In the present invention, the vesicle preferably contains a compound (channel substance) that forms a channel serving as a water-permeable portion. Examples of the channel substance include gramicidin, amphotericin B, hemolysin, aquaporin, and the like.

It is a typical explanatory view of experimental equipment. It is a longitudinal cross-sectional view of the flat membrane cell of FIG. It is a particle size distribution map of a vesicle. It is a particle size distribution map of a vesicle. It is a particle size distribution map of a vesicle.

  In the method of the present invention, a vesicle dispersion and a membrane body having selective permeability are brought into contact with each other to form a coating layer made of a phospholipid bilayer membrane on the surface of the membrane body.

  As this membrane body, an NF membrane, a UF membrane, or an MF membrane can be used, but an NF membrane and a UF membrane are preferred because the surface is flat, and an NF membrane is particularly preferred.

  In the present invention, a coating layer is formed on the surface of the membrane body by a vesicle fusion method using vesicles made of phospholipid and having an average particle size of 0.5 to 5 μm. Examples of the phospholipid constituting the vesicle include dipalmitoyl phosphatidylcholine (DPPC), dimyristoyl phosphatidylcholine (DMPC), distearoyl phosphatidylcholine (DSPC), palmitoyl oleoyl phosphatidylcholine (POPC), and the like.

  In forming the vesicles, the phospholipid is first dissolved in a solvent, preferably with the channel material. As the channel substance, gramicidin, amphotericin B, hemolysin, aquaporin and the like can be used.

  The mixing ratio of the phospholipid and the channel substance is preferably such that the ratio of the channel substance to the total of both is 1 to 20 mol%, particularly 3 to 10 mol%.

  The vesicle dispersion having an average particle size of 0.5 to 5 μm is not particularly limited, but can be produced by the following method, for example.

  First, a phospholipid and a channel substance are dissolved in a solvent. As a solvent for dissolving the phospholipid and the channel substance, chloroform, chloroform / methanol mixed solution, or the like can be used.

  Next, 0.1 to 1.0 wt%, particularly 0.2 to 0.5 wt% solution of phospholipid and channel substance is prepared and dried under reduced pressure to obtain a dry lipid membrane, and pure water is added thereto By setting the temperature higher than the phase transition temperature of the phospholipid, a vesicle dispersion having a spherical shell shape is obtained.

  In one embodiment of the present invention, the vesicle dispersion is filtered through a membrane having pores having a pore size of 0.05 to 0.8 μm (for example, polycarbonate track etching membrane) to have a particle size of 0.05 to 0.8 μm or less. A dispersion of spherical shell vesicles is used. Subsequently, the spherical shell vesicles are grown by a freeze-thaw method in which this vesicle dispersion is repeatedly held at a temperature higher than the phase transition temperature of the phospholipid and below the freezing temperature, so that the average particle size is 0.5. ˜5 μm.

  In another embodiment of the present invention, it is used as it is as a vesicle dispersion having an average particle size of 0.5 to 5 μm without performing such freeze-thaw treatment.

  The average particle diameter of the vesicles of the vesicle dispersion used in the present invention is preferably 0.5 to 5 μm, particularly preferably 1 to 5 μm. This vesicle dispersion may contain an average particle size of less than 0.5 μm (for example, a particle size of 0.1 μm to 0.5 μm). When a vesicle having a small particle diameter is contained in this way, the resulting film is densified. In addition, the particle size distribution of the vesicles in the vesicle dispersion is such that the 25% cumulative value of the scattering intensity by the dynamic light scattering method is 0.5 μm or more and the 75% cumulative value of the scattering intensity is 5 μm or less. It is preferable to make it.

  This vesicle dispersion is brought into contact with the membrane body. The temperature of the vesicle dispersion is set to be equal to or higher than the phase transition temperature, preferably 5 to 40 ° C., particularly 10 to 30 ° C. higher than the phase transition temperature of the phospholipid, and 0.5% in a state of being in contact with the vesicle dispersion. By maintaining ˜6 Hr, particularly about 1 to 3 Hr, vesicles are adsorbed on the surface of the membrane body to form a coating layer of the phospholipid bilayer membrane. Thereafter, the membrane main body with the coating layer is pulled up from the solution and washed with ultrapure water or pure water as necessary to obtain a selective permeable membrane having a coating layer of a phospholipid bilayer membrane.

  The thickness of the phospholipid bilayer membrane is preferably about 1 to 30 layers, particularly about 1 to 15 layers. Anionic substances such as polyacrylic acid, polystyrene sulfonic acid, and tannic acid may be adsorbed on the surface of the coating layer. Since the surface of the phospholipid bilayer membrane has a cationic hydrophilic group, it can be fixed by contacting an anionic substance.

  In the present invention, it is preferable to introduce a cationic lipid such as dimyris trimethyl ammonium propane (DMTAP) or dioleoyl trimethyl ammonium propane (DOTAP) into the vesicle. By introducing the cationic lipid in this way, a positive charge is imparted to the phospholipid vesicle. The reason is as follows.

  During vesicle fusion, the pH is lowered by the addition of HCl, so amphoteric phospholipids (DPPC, DMPC, etc.) have a positive charge. Accordingly, phospholipids are adsorbed on the support membrane without introducing DMTAP or the like. However, if cationic lipids such as DMTAP and DOTAP are not added, the pH becomes neutral when the film is washed with pure water after film formation. There is a possibility that the phenomenon of lipid peeling occurs. When a cationic lipid such as DMTAP or DOTAP is introduced into the vesicle, the phospholipid is prevented from peeling off. When POPC is used as the phospholipid, it is preferable to add DOTAP, which is an unsaturated cationic lipid, so as not to affect the phase transition temperature. The compounding ratio of the cationic lipid such as DMTAP and the amphoteric phospholipid such as DPPC is preferably a molar ratio, DMTAP / (phospholipid + DMTAP) = 5 to 40 mol%, more preferably 10 to 30 mol. %.

  Hereinafter, examples and comparative examples will be described.

[NF membrane]
In the following examples and comparative examples, a sulfonated polyethersulfone-based nanofiltration membrane NTR-7450 (manufactured by Nitto Denko, pure water permeability coefficient 27-38 × 10 ⁻¹² m / (sPa), permeation flux 1 as an NF membrane .75 to 2.46 m ³ / (m ² d), and a desalting rate of 0.50 to 0.55) was used.

[Membrane performance testing equipment]
The film performance evaluation apparatus used in the following examples and comparative examples is shown in FIGS. The test membrane M is attached to the flat membrane cell 10 as shown in FIG. In this cell 10, a porous support plate 13 is sandwiched between a lower half body 11 and an upper half body 12, a test membrane M is disposed on the lower surface side of the porous support plate 13, and sealed with an O-ring 14. It is comprised so that it may do. A stirrer 17 of a stirrer 16 is disposed in the lower half body 11.

  The treated water is supplied from the inlet 2 into the lower half 11 by the pump 1, the permeated water is discharged from the outlet 3, and the concentrated water is discharged from the outlet 4 to the outlet pipe 5. The exhaust pipe 5 is provided with a back pressure valve 6.

[Method for evaluating membrane performance]
As evaluation water for the membrane performance, pure water, a 500 ppm sodium chloride aqueous solution, and a 100 ppm urea aqueous solution were used. The operating pressure at that time is 0.75 MPa, and the water temperature is 25 ° C. ± 2 ° C. The permeation flux, pure water permeation coefficient, desalination rate, and urea rejection rate were determined by the following equations.
Permeation flux [m / s] = permeation flow rate [m ³ / s] / membrane area [m ² ] × temperature correction coefficient [−]
Pure water permeability coefficient [m / (sPa)] = pure water flux [m / s] / operating pressure [Pa]
Desalination rate [−] = 1−permeated water electrical conductivity [mS / m] / concentrated water electrical conductivity [mS / m]
Urea rejection rate [−] = 1−permeated water TOC [mg / L] / concentrated water TOC [mg / L]

[Measurement method of phase transition temperature]
The phase transition temperature was measured by DSC (differential operation calorimeter). The device used is a DSC8500 manufactured by Perkin Elmer. The phase transition temperature of the phospholipid or its channel substance mixture measured by this apparatus is as follows.
DPPC / DMTAP / GA (molar ratio 76/19/5): 45.23 ° C.
DPPC: 41.4 ° C
DMPC: 23.9 ° C
DMPC / DMTAP / GA (molar ratio 76/19/5): 26.9 to 29.9 ° C
POPC: -2.9 ° C

[Example 1]
Dipalmitoylphosphatidylcholine (DPPC) was used as the phospholipid constituting the vesicle, dimyristoyltrimethylammoniumpropane (DMTAP) was used as the cationic lipid, and gramidine A (GA) was used as the channel substance to be introduced into the vesicle.

  The phospholipid and the channel substance were dissolved in 50:50 vol% chloroform / methanol, and a 0.3 wt% solution of DPPC / DMTAP / GA = 76/19/5 (mol%) was prepared as a mixing ratio. For the production of vesicles, pure water was added to the dry lipid film remaining in the container by evaporating the organic solvent under reduced pressure, and the thin film composed of DPPC / DMTAP / GA was hydrated at 60 ° C. The resulting spherical shell vesicle dispersion is filtered through a polycarbonate track etching membrane having a pore size of 0.2 μm to reduce the particle size to 0.2 μm or less, and then immersed in liquid nitrogen and a 60 ° C. hot water bath alternately. Were grown by freeze-thaw method repeated 5 times.

  The vesicle dispersion was diluted with pure water so that the phospholipid concentration was 1.5 mM, and diluted hydrochloric acid was added to adjust the pH to 2.0. The result of measuring the particle size distribution of the vesicles by the dynamic light scattering method (manufactured by Otsuka Electronics, ELSZ-2) is shown in FIG. The average particle diameter of the prepared DPPC / DMTAP / GA vesicle was 2300 nm (2.3 μm). This vesicle is substantially free of particles having a particle size of 0.5 μm or less. This vesicle dispersion was brought into contact with an NF membrane NTR-7450 (Nitto Denko) and left to stand in a thermostatic chamber heated to 60 ° C. for 3 hours to adsorb the vesicle on the surface of the NF membrane. Thereafter, the membrane was pulled up from the water and washed with pure water.

When the characteristics of the NF membrane on which the vesicle adsorption layer made of DPPC / DMTAP / GA was formed were evaluated, the pure water permeability coefficient was 2.2 × 10 ⁻¹² min / (sPa), and the pure water permeability flux was 0.14 m ^3. / (M ² d), the salt rejection was 0.95, and the urea rejection was 0.45. The thickness of the phospholipid bilayer calculated from the amount of adsorption was 10 layers.

[Example 2]
Dimyristoylphosphatidylcholine (DMPC) was used as the phospholipid constituting the vesicle, DMTAP was used as the cationic lipid, and GA was used as the channel substance to be introduced into the vesicle. Phospholipids, cationic lipids and channel substances were dissolved in 50:50 vol% chloroform / methanol, and a 0.3 wt% solution of DMPC / DMTAP / GA = 76/19/5 [mol%] was prepared as a mixing ratio. . After depressurizing this solution and evaporating the organic solvent, pure water was added to the dry lipid membrane remaining in the container, and the thin film composed of DMPC / DMTAP / GA was hydrated at 45 ° C. Subsequently, it diluted with pure water so that the phospholipid density | concentration of a vesicle dispersion liquid might be set to 1.5 mM, and diluted hydrochloric acid was added and pH was adjusted to 2.0. The result of measuring the particle size distribution of the vesicles by the dynamic light scattering method (using the same apparatus as in Example 1) is shown in FIG. The prepared DMPC / DMTAP / GA vesicle had an average particle size of 940 nm (0.94 μm), and contained 4% fine particles having a particle size of 0.1 to 0.2 μm in terms of scattering intensity distribution.

The vesicle dispersion is brought into contact with the NF film NTR-7450 (Nitto Denko) and left in a thermostatic chamber heated to 45 ° C. for 3 hours to adsorb the vesicles on the surface of the NF film, thereby coating the DMPC / DMTAP / GA coating layer. An NF membrane having When the characteristics of the NF membrane with a coating layer were evaluated, the pure water permeability coefficient was 2.1 × 10 ⁻¹² m / (sPa), the pure water permeability flux was 0.14 m ³ / (m ² d), and the salt rejection was 0. The urea rejection was 0.58. The thickness of the phospholipid bilayer calculated from the amount of adsorption was 5 layers.

[Comparative Example 1]
Instead of performing a freeze-thaw method in which a thin film composed of DPPC / DMTAP / GA is hydrated at 60 ° C. and then alternately immersed in liquid nitrogen and a 60 ° C. water bath five times, a vesicle solution is used. A vesicle dispersion having a particle size of less than 0.1 μm and an average particle size of 0.08 μm was prepared by filtering through a polycarbonate track etching membrane having a pore size of 0.1 μm, and Example 1 was used except that this dispersion was used. The NF membrane in which the adsorption layer of DPPC / DMTAP / GA was formed was manufactured in the same procedure as described above. The desalting rate of this membrane was 0.75 or less, and sufficient desalting performance was not obtained.

[Comparative Example 2]
A thin film composed of DMPC / DMTAP / GA is hydrated at 45 ° C., and then the vesicle solution is filtered through a polycarbonate track etching film having a pore diameter of 0.1 μm. A NF membrane having an adsorption layer of DMPC / DMTAP / GA was produced in the same manner as in Example 2 except that a dispersion of 08 μm vesicle was prepared and this dispersion was used. The desalting rate of this membrane was 0.75 or less, and sufficient desalting performance was not obtained.

[Comparative Example 3]
Other than contacting the vesicle dispersion with the NF membrane NTR-7450 (Nitto Denko) and leaving it in a 45 ° C constant temperature bath for 3 hours, instead of leaving it in a 25 ° C constant temperature bath for 3 hours Manufactured an NF film having a DMPC / DMTAP / GA adsorption layer formed in the same procedure as in Example 2.

When the characteristics of the NF membrane with this coating layer (adsorption layer) were evaluated, the pure water permeability coefficient 12 × 10 ⁻¹² min / (sPa), the pure water permeability flux 0.78 m ³ / (m ² (D)), The salt rejection was 0.1 or less and the urea rejection was 0. From Comparative Example 3, it was confirmed that when the contact temperature was lower than the phase transition temperature of DMPC / DMTAP / GA (molar ratio 76/19/5), sufficient desalting performance could not be obtained.

[Example 3]
Palmitoyl oleoyl phosphatidylcholine (POPC) was used as the lipid constituting the vesicle, dioleoyltrimethylammoniumpropane (DOTAP) was used as the cationic lipid, and gramidine A (GA) was used as the channel substance to be introduced into the vesicle. The lipid and the channel substance were dissolved in 50:50 vol% chloroform / methanol, and a solution having a mixing ratio of POPC / DOTAP / GA = 76/19/5 [mol%] was prepared.

  For the production of vesicles, the organic solvent was evaporated under reduced pressure to dry the lipid, and then pure water was added to the dry lipid film remaining in the container, and a thin film composed of POPC / DOTAP / GA was formed at 25 ° C. Hydrated with. The obtained vesicle solution was filtered through a polycarbonate track etching film to reduce the particle size to about 0.2 μm, and then the operation of alternately immersing in liquid nitrogen and a 40 ° C. hot water bath was repeated five times by a freeze-thaw method. Large single film vesicles were prepared.

  The solution was diluted with pure water so that the lipid concentration of the vesicle solution was 1.5 mM, and diluted hydrochloric acid was added to adjust the pH to 2.0. The result of measuring the particle size distribution of the vesicles by the dynamic light scattering method (using ELSZ-2 manufactured by Otsuka Electronics) is shown in FIG.

The vesicle solution and the nanofiltration membrane NTR-7450 (Nitto Denko) were contacted and allowed to stand at 25 ° C. for 3 hours to adsorb the lipid layer on the surface of the NF membrane to produce an NF membrane with an adsorption layer of POPC / DOTAP / GA. . This membrane had a pure water permeation coefficient of 3.6 × 10 ⁻¹³ m / (sPa), a pure water permeation flux of 0.027 m ³ / (m ² d), and a desalting rate of 0.97. The thickness of the phospholipid bilayer calculated from the amount of adsorption was 5 layers. Since the phase transition temperature of the vesicle to be adsorbed is 0 ° C. or lower and the temperature at the time of adsorption is 25 ° C., it is considered that a membrane having separation performance was obtained.

10 Flat membrane cell 13 Porous support plate

Claims (7)

A method for producing a selectively permeable membrane comprising a membrane body having selective permeability and a coating layer comprising a phospholipid bilayer membrane formed on the surface of the membrane body,
A selective permeable membrane having a vesicle fusion step in which a dispersion of a vesicle of a phospholipid bilayer membrane and the membrane body are brought into contact with each other at a temperature higher than the phase transition temperature of the phospholipid bilayer membrane to form the coating layer In the manufacturing method of
A method for producing a selective permeable membrane, wherein the vesicle has an average particle size of 0.5 to 5 µm.   2. The method for producing a selective permeable membrane according to claim 1, wherein the amphiphilic molecule constituting the phospholipid bilayer has a molecular weight of 200 to 2,000.   3. The method for producing a selective permeable membrane according to claim 1, wherein the vesicle dispersion contains fine vesicles having a particle diameter of less than 0.5 μm.   4. The method for manufacturing a selective permeable membrane according to claim 1, wherein the vesicle contains a channel substance.   5. The method for producing a selective permeable membrane according to claim 4, wherein the channel substance comprises gramicidin, amphotericin B, hemolysin, or aquaporin.   6. The method of manufacturing a selective permeable membrane according to claim 1, wherein the membrane body is an NF membrane.   The selective permeable membrane manufactured by the method of any one of Claim 1 thru | or 6.

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