CN102941023A - Bacteria cellulose hemodialysis membrane - Google Patents
Bacteria cellulose hemodialysis membrane Download PDFInfo
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- CN102941023A CN102941023A CN2012104684468A CN201210468446A CN102941023A CN 102941023 A CN102941023 A CN 102941023A CN 2012104684468 A CN2012104684468 A CN 2012104684468A CN 201210468446 A CN201210468446 A CN 201210468446A CN 102941023 A CN102941023 A CN 102941023A
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Abstract
The invention discloses a bacteria cellulose hemodialysis membrane and a preparation method of the bacteria cellulose hemodialysis membrane. The preparation method comprises the following steps of activating bacteria cellulose powder by a NaOH (sodium hydroxide) solution, then dissolving the bacteria cellulose powder in a LiCl/DMAC (lithium chloride/N, N-dimethylacetamide) solvent system under a heating condition, cooling the dissolving system, standing and scraping the membrane; slowly immersing a membrane scraping plate in a coagulating bath, standing, and taking the membrane scraping plate out of the coagulating bath after the membrane strips from the membrane scraping plate so as to obtain the bacteria cellulose regeneration membrane for hemodialysis. Bacteria cellulose is used as raw material, the regeneration cellulose membrane is prepared by an immersing, precipitating and phase conversion method, and then the regeneration cellulose membrane can be used as a novel hemodialysis membrane for treating acute and chronic renal failure. Compared with the traditional hemodialysis membrane, the bacteria cellulose hemodialysis membrane has the advantages that the chemical purity is high, the biocompatibility is high, the mechanical strength is high, the water ultrafiltering rate is high, the simple, environment-friendly, moderate and controllable effects are realized in the preparation process, and the bacteria cellulose hemodialysis membrane is suitable for the industrial production of the hemodialysis membranes with different requirements.
Description
One, technical field
The present invention relates to the technical field of hemodialysis membrane, particularly a kind of bacteria cellulose hemodialysis membrane.
Two, background technology
Haemodialysis is to remove harmful substance in the body by mechanism such as disperse, convection current, ultrafiltration, absorption, is the major measure for the treatment of acute or chronic renal failure, and the performance of hemodialysis membrane determines the effect of dialysis treatment.Hemodialysis membrane mainly comprises regenerated cellulose hemodialysis membrane, modified cellulose hemodialysis membrane, artificial dextran dialysis membrane etc.Wherein the regenerated cellulose hemodialysis membrane has the advantages such as price is low, hydrophily is high, mechanical strength is large, good, the little molecule toxin removing of stain resistance ability is strong, is to study the earliest, also is a most widely used class hemodialysis membrane.The most frequently used regenerated cellulose hemodialysis membrane is CUP element film at present, but CUP element film can not effectively be removed the noxious material (as: β-microglobulin) of medium molecule, and preparation process causes serious pollution to environment.
Bacteria cellulose is that bacterium is secreted into extracellular product, is formed by glucose polymerisation.Compare with plant cellulose, bacteria cellulose has many good performances, as: high-purity, high-crystallinity, high polymerization degree, high Young's modulus and nanofibrous structures, and have good biocompatibility and biosynthesis Modulatory character.Therefore bacteria cellulose is widely used in biomedical materials field, as scalding auxiliary material, artificial blood vessel, tissue engineering bracket etc.Brazil has reported more than the 400 routine examples of processing burn, scald and chronic ulcer of skin and dermatoplasty etc. with bacteria cellulose film since 1987.The former beautiful woman of domestic merchant (bacteria cellulose is as the application study [D] of biomedical material. University Of Science and Technology Of Tianjin, 2008) etc. research is found, keratocyte can be grown preferably take bacterial cellulose wet-coating as support, illustrates that bacteria cellulose can be used as the good support of keratocyte.The successful Application of bacteria cellulose aspect medical material shows that it meets the physics of the required uniqueness of medical material, chemical property and bio-compatible performance preferably.
Document (Chen Chuchu, Li Dagang, Deng Qiaoyun. a kind of method of utilizing bacteria cellulose to prepare the high barrier packaging film, publication No.: CN102391534A, the applying date: 2010.11.18) disclose a kind of method of utilizing bacteria cellulose to prepare the high barrier packaging film, this invention utilizes the film of LiCl/DMAC dicyandiamide solution dissolution of bacteria cellulose preparation to have certain flexibility, mechanical strength and barrier property.But its film-forming method is to film by glass bar coating or the tape casting, and process is comparatively coarse, and the regeneration membrane microstructure that obtains is inhomogeneous, has affected accuracy and the reliability of made thin film mechanical performance test data; In addition, the bacterial cellulose solution Cmax only is about 1.5% (wt%) in this invention, far below the Cmax of this patent 3.0% (wt%), causes easily diaphragm to shrink and fold in the low concentration solution film-forming process.
Three, summary of the invention
It is strong and cellulose impurities removed the easy bacteria cellulose hemodialysis membrane of process to the purpose of this invention is to provide a kind of mechanical strength height, good biocompatibility, Dusuqing removing solid capacity.
Realize that technical solution of the present invention is: a kind of bacteria cellulose hemodialysis membrane, it is characterized in that this hemodialysis membrane by bacteria cellulose preparation and get, and this hemodialysis membrane is the water white transparency shape, have densification, uniform microstructure; The hot strength of described hemodialysis membrane is 28.1MPa～41.4Mpa, water ultrafiltration rate UFR 〉=20mLm
-2H
-1MmHg
-1, bovine serum albumin rejection 〉=96%, urea dialysis permeability 〉=100 * 10
4Cmmin
-1, cobalamin dialysis permeability 〉=20 * 10
4Cmmin
-1, above performance parameter all satisfies the requirement of haemodialysis.
The water ultrafiltration rate UFR of bacteria cellulose hemodialysis membrane of the present invention is 20.1mLm
-2H
-1MmHg
-1～23mLm
-2H
-1MmHg
-1, the bovine serum albumin rejection is 96%～98.5%, urea dialysis permeability is 118 * 10
4Cmmin
-1～168 * 10
4Cmmin
-1, Cobastab
12The dialysis permeability is 60 * 10
4Cmmin
-1～75 * 10
4Cmmin
-1
Prepare the method for bacteria cellulose hemodialysis membrane of the present invention, may further comprise the steps:
The first step, the bacteria cellulose preliminary treatment: the NaOH solution that bacteria cellulose is soaked in weight 3%～9% concentration also stirs, and is then extremely neutral with the deionized water washing, uses soaked in absolute ethyl alcohol again, dries at last;
Second step, the preparation of LiCl/DMAC dissolution system: the LiCl powder is put into air dry oven, in 80～150 ℃ of lower oven dry, then be mixed with the LiCl/DMAC solution of weight 8% concentration with the DMAC solvent, airtight preservation;
The 3rd step, the dissolving of bacteria cellulose powder: with the pretreated bacteria cellulose of the first step, mix with the LiCl/DMAC solution of second step preparation, add the bacterial cellulose solution that thermal agitation is configured to weight 2.0%～3.0% concentration, cooling after the bacteria cellulose dissolving, the refrigerator standing and defoaming;
In the 4th step, the preparation of bacteria cellulose hemodialysis membrane: the bacterial cellulose solution after the processing of the 3rd step is poured on the knifing machine, and adjusting the scraper height is 450 μ m, and knifing speed is 0.5mmin
-1Carry out knifing, will scrape immediately after knifing finishes in the template immersion coagulating bath and solidify, get the solid gel film, this solid gel film is washed with running water, soak with deionized water again; The solid gel film that cleans up is soaked in the plasticiser plastifies, then be tiled on the clean glass plate and dry under natural environment, obtain bacteria cellulose haemodialysis membrane sample;
The 5th step, the bacteria cellulose haemodialysis membrane sample of gained is characterized by SEM and the film properties test, estimate the requirement of whether satisfying haemodialysis, if do not satisfy, adjust preparation condition according to test result, continue to prepare the bacteria cellulose hemodialysis membrane according to the method in the first step～the 4th step; The preparation condition of wherein adjusting comprises the concentration of the composition of preprocessing process, the solution concentration after the bacteria cellulose dissolving, coagulating bath of bacteria cellulose powder and concentration, setting temperature, plasticiser.
The preparation method of bacteria cellulose hemodialysis membrane of the present invention, coagulating bath is the DMAC aqueous solution of 10～26 ℃ of temperature, weight 20～40% concentration described in the 4th step, perhaps the ethanolic solution of 4 ℃ of temperature, weight 95% concentration; Plasticiser described in the 4th step is the glycerine water solution of 26 ℃ of temperature, weight 10%～20% concentration.
The preparation method of bacteria cellulose hemodialysis membrane of the present invention, the haemodialysis membrane sample that described SEM of the 5th step characterizes is abundant swelling in deionized water first, then tests behind liquid nitrogen frozen, brittle failure, metal spraying; The 5th step, described film properties test comprised hot strength test, the test of water ultrafiltration rate, the test of bovine serum albumin rejection, the test of urea dialysis permeability and the test of cobalamin dialysis permeability, and is specific as follows:
1) hot strength test: the haemodialysis membrane sample of preparation is tested with the microcomputer controlled electronic universal tensile testing machine;
2) water ultrafiltration rate test: use deionized water, under 0.1MPa, utilize the ultrafiltration cup to carry out ultrafiltration;
3) bovine serum albumin rejection test: working concentration is 1.0mgmL
-1BSA solution, under 0.1MPa, utilize the ultrafiltration cup to carry out ultrafiltration;
4) urea dialysis permeability test: with the hemodialysis membrane specimen holder of preparation in the middle of osmotic cell, on one side osmotic cell adds 0.1mgmL
-1Urea liquid, another side adds deionized water, and whole osmotic cell is put into water-bath, and constant temperature keeps 37 ℃ to be tested;
5) Cobastab
12Dialysis permeability test: with the hemodialysis membrane specimen holder of preparation in the middle of osmotic cell, on one side osmotic cell adds 0.05mgmL
-1Cobastab
12Solution, another side adds deionized water, with black plastic film osmotic cell is wrapped up, and whole osmotic cell is put into water-bath, and constant temperature keeps 37 ℃ to be tested.
The present invention compared with prior art, its remarkable advantage is: 1) preparation process is easy, and is easy to operate, and mild condition, raw material is easy to reclaim, and is little to ambient influnence; 2) employed dicyandiamide solution is optimum, and cellulose dissolution velocity in this system is very fast, produce without derivative, and be difficult for causing cellulosic degraded, and the cellulose solution clear of gained, at room temperature highly stable, but long preservation; 3) hemodialysis membrane of preparation is except possessing good biocompatibility and mechanical strength, and its heat endurance is also higher, can keep original physicochemical properties constant during high-temperature sterilization; 4) hemodialysis membrane of preparation satisfies the related request of haemodialysis, and urea dialysis permeability and Cobastab
12The dialysis permeability all regenerated cellulose haemodialysis film properties than commercially available is good.
Four description of drawings
Fig. 1 is the experimental procedure schematic diagram of bacteria cellulose hemodialysis membrane of the present invention.
Fig. 2 is the SEM figure in bacteria cellulose hemodialysis membrane of the present invention cross section.
Fig. 3 is the SEM figure on bacteria cellulose hemodialysis membrane of the present invention surface.
Five specific embodiment
Below in conjunction with accompanying drawing the present invention is done and to describe in further detail.
A kind of bacteria cellulose hemodialysis membrane is characterized in that this hemodialysis membrane by bacteria cellulose preparation and get, and this hemodialysis membrane is the water white transparency shape, has densification, uniform microstructure; The hot strength of described hemodialysis membrane is 28.1MPa～41.4Mpa, water ultrafiltration rate UFR 〉=20mLm
-2H
-1MmHg
-1, bovine serum albumin rejection 〉=96%, urea dialysis permeability 〉=100 * 10
4cMmin
-1, Cobastab
12Dialysis permeability 〉=20 * 10
4Cmmin
-1, above performance parameter all satisfies the requirement of haemodialysis.
The water ultrafiltration rate UFR of bacteria cellulose hemodialysis membrane of the present invention is 20.1mLm
-2H
-1MmHg
-1～23mLm
-2H
-1MmHg
-1, the bovine serum albumin rejection is 96%～98.5%, urea dialysis permeability is 118 * 10
4Cmmin
-1～168 * 10
4Cmmin
-1, Cobastab
12The dialysis permeability is 60 * 10
4Cmmin
-1～75 * 10
4Cmmin
-1
As shown in Figure 1, prepare the method for bacteria cellulose hemodialysis membrane of the present invention, may further comprise the steps:
The first step, the bacteria cellulose preliminary treatment: the NaOH solution that bacteria cellulose is soaked in weight 3%～9% concentration also stirs, and is then extremely neutral with the deionized water washing, uses soaked in absolute ethyl alcohol again, dries at last;
Second step, the preparation of LiCl/DMAC dissolution system: the LiCl powder is put into air dry oven, in 80～150 ℃ of lower oven dry, then be mixed with the LiCl/DMAC solution of weight 8% concentration with the DMAC solvent, airtight preservation;
The 3rd step, the dissolving of bacteria cellulose powder: with the pretreated bacteria cellulose of the first step, mix with the LiCl/DMAC solution of second step preparation, add the bacterial cellulose solution that thermal agitation is configured to weight 2.0%～3.0% concentration, cooling after the bacteria cellulose dissolving, the refrigerator standing and defoaming;
In the 4th step, the preparation of bacteria cellulose hemodialysis membrane: the bacterial cellulose solution after the processing of the 3rd step is poured on the knifing machine, and adjusting the scraper height is 450 μ m, and knifing speed is 0.5mmin
-1Carry out knifing, will scrape immediately after knifing finishes in the template immersion coagulating bath and solidify, get the solid gel film, this solid gel film is washed with running water, soak with deionized water again; With the solid gel film that cleans up be soaked in plasticiser namely in plasticizing, then be tiled on the clean glass plate and dry under natural environment, obtain bacteria cellulose haemodialysis membrane sample; Described coagulating bath is the DMAC aqueous solution of 10～26 ℃ of temperature, weight 20～40% concentration, perhaps the ethanolic solution of 4 ℃ of temperature, weight 95% concentration; Described plasticiser is the glycerine water solution of 26 ℃ of temperature, weight 10%～20% concentration.
The 5th step, the bacteria cellulose haemodialysis membrane sample of gained is characterized by SEM and the film properties test, estimate the requirement of whether satisfying haemodialysis, if do not satisfy, adjust preparation condition according to test result and continue to prepare the bacteria cellulose hemodialysis membrane according to the method in the first step～the 4th step.The preparation condition of wherein adjusting comprises the concentration of the composition of preprocessing process, the solution concentration after the bacteria cellulose dissolving, coagulating bath of bacteria cellulose powder and concentration, setting temperature, plasticiser; The haemodialysis membrane sample that described SEM characterizes is abundant swelling in deionized water first, then tests behind liquid nitrogen frozen, brittle failure, metal spraying; Described film properties test comprises hot strength test, the test of water ultrafiltration rate, the test of bovine serum albumin rejection, the test of urea dialysis permeability and the test of cobalamin dialysis permeability, and is specific as follows:
1) hot strength test: the haemodialysis membrane sample of preparation is tested with the microcomputer controlled electronic universal tensile testing machine;
2) water ultrafiltration rate test: use deionized water, under 0.1MPa, utilize the ultrafiltration cup to carry out ultrafiltration;
3) bovine serum albumin rejection test: working concentration is 1.0mgmL
-1BSA solution, under 0.1MPa, utilize the ultrafiltration cup to carry out ultrafiltration;
4) urea dialysis permeability test: with the hemodialysis membrane specimen holder of preparation in the middle of osmotic cell, on one side osmotic cell adds 0.1mgmL
-1Urea liquid, another side adds deionized water, and whole osmotic cell is put into water-bath, and constant temperature keeps 37 ℃ to be tested;
5) Cobastab
12Dialysis permeability test: with the hemodialysis membrane specimen holder of preparation in the middle of osmotic cell, on one side osmotic cell adds 0.05mgmL
-1Cobastab
12Solution, another side adds deionized water, with black plastic film osmotic cell is wrapped up, and whole osmotic cell is put into water-bath, and constant temperature keeps 37 ℃ to be tested.
Below in conjunction with specific embodiment the present invention is done and to describe in further detail.
Embodiment 1
In conjunction with Fig. 1, prepare bacteria cellulose film hemodialysis membrane of the present invention, may further comprise the steps:
The first step, bacteria cellulose preliminary treatment: get a certain amount of bacteria cellulose powder and cross 150 purpose sieves, the powder that sieves out is soaked in 3% the NaOH solution, after stirring 3h under the room temperature, vacuum filtration, use the deionized water cyclic washing, be neutrality to cleaning solution till, use again soaked in absolute ethyl alcohol 3 times, each 3h that keeps, it is dry to put at last vacuum drying chamber, and 80 ℃ of baking temperatures are dried to till the powder constant weight;
Second step, the preparation of LiCl/DMAC dissolution system: the analytically pure LiCl particle of certain mass is put into air dry oven, in 80 ℃ of lower oven dry 24h, LiCl powder and a certain amount of DMAC solvent and at room temperature stirring with oven dry, be mixed with the LiCl/DMAC solution of weight 8% concentration, the solution clear, airtight preservation;
The 3rd step, the dissolving of bacteria cellulose powder: will activate good bacteria cellulose powder, and put into the LiCl/DMAC solution that has prepared, and stir 3 hours in 100 ℃ of lower magnetic forces, and be mixed with the cellulose solution of weight 3% concentration.Put into 4 ℃ of refrigerator standing and defoaming 48h, whole process bottle sealing after being cooled to room temperature;
In the 4th step, the preparation of bacteria cellulose hemodialysis membrane: the cellulose solution of clear is poured into scrapes on the mould machine, adjusting the scraper height is 450 μ m, and knifing speed is transferred to 0.5mmin
-1, will scraping immediately lamina membranacea after knifing finishes, to put into coagulating bath be the 40%DMAC aqueous solution, temperature remains on 20 ℃, solidify 10min, then the solid gel film is washed 12h in the running water that flows, soak with deionized water again, with the solid gel film that cleans up, be immersed in the glycerine water solution that certain density plasticiser is weight 15% concentration, temperature remains on 26 ℃, plasticizing 10min, take out, be tiled on the clean glass plate, natural drying, obtain bacteria cellulose haemodialysis membrane sample;
The 5th step, the bacteria cellulose hemodialysis membrane of gained is tested by SEM sign and film properties, estimate the requirement of whether satisfying haemodialysis; The bacteria cellulose hemodialysis membrane that described SEM characterizes is abundant swelling in deionized water first, then tests behind liquid nitrogen frozen, brittle failure, metal spraying; Described film properties test comprises hot strength test, the test of water ultrafiltration rate, the test of bovine serum albumin rejection, the test of urea dialysis permeability and the test of cobalamin dialysis permeability, and is specific as follows:
1) hot strength test: the haemodialysis membrane sample of preparation is cut into the strip batten of about 5mm * 40mm, tests with the microcomputer controlled electronic universal tensile testing machine, draw speed is 20mmmin
-1, test clip is apart from being 20mm, recording hot strength is 37.9MPa;
2) water ultrafiltration rate test: use deionized water, utilize the ultrafiltration cup to carry out ultrafiltration under 0.1MPa the haemodialysis membrane sample for preparing, recording the water ultrafiltration rate is 20.1mLm
-2H
-1MmHg
-1
3) bovine serum albumin rejection test: working concentration is 1.0mgmL
-1BSA solution, with the preparation the haemodialysis membrane sample under 0.1MPa, utilize the ultrafiltration cup to carry out ultrafiltration, recording the bovine serum albumin rejection is 96.5%;
4) urea dialysis permeability test: with the hemodialysis membrane specimen holder of preparation in the middle of osmotic cell, on one side osmotic cell adds 0.1mgmL
-1Urea liquid, another side adds deionized water, and whole osmotic cell is put into water-bath, and constant temperature keeps 37 ℃, and recording urea dialysis permeability is 160 * 10
4Cmmin
-1
5) Cobastab
12Dialysis permeability test: with the hemodialysis membrane specimen holder of preparation in the middle of osmotic cell, on one side osmotic cell adds 150mL, 0.05mgmL
-1Cobastab
12Solution, another side adds the 150mL deionized water, with black plastic film osmotic cell is wrapped up, and whole osmotic cell is put into water-bath, and constant temperature keeps 37 ℃, records Cobastab
12The dialysis permeability is 71 * 10
4Cmmin
-1
Embodiment 2
In conjunction with Fig. 1, prepare bacteria cellulose film hemodialysis membrane of the present invention, may further comprise the steps:
The first step, bacteria cellulose preliminary treatment: get a certain amount of bacteria cellulose powder and cross 150 purpose sieves, the powder that sieves out is soaked in 6% the NaOH solution, after stirring 3h under the room temperature, vacuum filtration, use the deionized water cyclic washing, be neutrality to cleaning solution till, use again soaked in absolute ethyl alcohol 4 times, each 3h that keeps, it is dry to put at last vacuum drying chamber, and 80 ℃ of baking temperatures are dried to till the powder constant weight;
Second step, the preparation of LiCl/DMAC dissolution system: the analytically pure LiCl particle of certain mass is put into air dry oven, in 110 ℃ of lower oven dry 24h, LiCl powder and a certain amount of DMAC solvent and at room temperature stirring with oven dry, be mixed with the LiCl/DMAC solution of weight 8% concentration, the solution clear, airtight preservation;
The 3rd step, the dissolving of bacteria cellulose powder: will activate good bacteria cellulose powder, and put into the LiCl/DMAC solution that has prepared, and stir 3 hours in 100 ℃ of lower magnetic forces, and be mixed with the cellulose solution of weight 3% concentration.Put into 4 ℃ of refrigerator standing and defoaming 48h, whole process bottle sealing after being cooled to room temperature;
In the 4th step, the preparation of bacteria cellulose hemodialysis membrane: the cellulose solution of clear is poured into scrapes on the mould machine, adjusting the scraper height is 450 μ m, and knifing speed is transferred to 0.5mmin
-1, will scrape immediately lamina membranacea after knifing finishes and put into i.e. 95% ethanol water of coagulating bath, temperature remains on 4 ℃, solidify 10min, then the solid gel film is washed 12h in the running water that flows, soak with deionized water again, with the solid gel film that cleans up, be immersed in the glycerine water solution that certain density plasticiser is weight 20% concentration, temperature remains on 26 ℃, plasticizing 10min, take out, be tiled on the clean glass plate, natural drying, obtain bacteria cellulose haemodialysis membrane sample;
The 5th step, the bacteria cellulose hemodialysis membrane of gained is tested by SEM sign and film properties, estimate the requirement of whether satisfying haemodialysis; The bacteria cellulose hemodialysis membrane that described SEM characterizes is abundant swelling in deionized water first, then tests behind liquid nitrogen frozen, brittle failure, metal spraying; Described film properties test comprises hot strength test, the test of water ultrafiltration rate, the test of bovine serum albumin rejection, the test of urea dialysis permeability and the test of cobalamin dialysis permeability, and is specific as follows:
1) hot strength test: the haemodialysis membrane sample of preparation is cut into the strip batten of about 5mm * 40mm, tests with the microcomputer controlled electronic universal tensile testing machine, draw speed is 20mmmin
-1, test clip is apart from being 20mm, recording hot strength is 41.4MPa;
2) water ultrafiltration rate test: use deionized water, utilize the ultrafiltration cup to carry out ultrafiltration under 0.1MPa the haemodialysis membrane sample for preparing, recording the water ultrafiltration rate is 21.0mLm
-2H
-1MmHg
-1
3) bovine serum albumin rejection test: working concentration is 1.0mgmL
-1BSA solution, with the preparation the haemodialysis membrane sample under 0.1MPa, utilize the ultrafiltration cup to carry out ultrafiltration, recording the bovine serum albumin rejection is 98.5%;
4) urea dialysis permeability test: with the hemodialysis membrane specimen holder of preparation in the middle of osmotic cell, on one side osmotic cell adds 0.1mgmL
-1Urea liquid, another side adds deionized water, and whole osmotic cell is put into water-bath, and constant temperature keeps 37 ℃, and recording urea dialysis permeability is 118 * 10
4Cmmin
-1
5) Cobastab
12Dialysis permeability test: with the hemodialysis membrane specimen holder of preparation in the middle of osmotic cell, on one side osmotic cell adds 0.05mgmL
-1Cobastab
12Solution, another side adds deionized water, with black plastic film osmotic cell is wrapped up, and whole osmotic cell is put into water-bath, and constant temperature keeps 37 ℃, records Cobastab
12The dialysis permeability is 60 * 10
4Cmmin
-1
Embodiment 3
In conjunction with Fig. 1, prepare bacteria cellulose film hemodialysis membrane of the present invention, may further comprise the steps:
The first step, bacteria cellulose preliminary treatment: get a certain amount of bacteria cellulose powder and cross 150 purpose sieves, the powder that sieves out is soaked in 6% the NaOH solution, after stirring 3h under the room temperature, vacuum filtration, use the deionized water cyclic washing, be neutrality to cleaning solution till, use again soaked in absolute ethyl alcohol 5 times, each 3h that keeps, it is dry to put at last vacuum drying chamber, and 80 ℃ of baking temperatures are dried to till the powder constant weight;
Second step, the preparation of LiCl/DMAC dissolution system: the analytically pure LiCl particle of certain mass is put into air dry oven, in 130 ℃ of lower oven dry 24h, LiCl powder and a certain amount of DMAC solvent and at room temperature stirring with oven dry, be mixed with the LiCl/DMAC solution of weight 8% concentration, the solution clear, airtight preservation;
The 3rd step, the dissolving of bacteria cellulose powder: will activate good bacteria cellulose powder, and put into the LiCl/DMAC solution that has prepared, and stir 3 hours in 100 ℃ of lower magnetic forces, and be mixed with the cellulose solution of weight 2.5% concentration.Put into 4 ℃ of refrigerator standing and defoaming 48h, whole process bottle sealing after being cooled to room temperature;
In the 4th step, the preparation of bacteria cellulose hemodialysis membrane: the cellulose solution of clear is poured into scrapes on the mould machine, adjusting the scraper height is 450 μ m, and knifing speed is transferred to 0.5mmin
-1, will scraping immediately lamina membranacea after knifing finishes, to put into coagulating bath be the 30%DMAC aqueous solution, temperature remains on 26 ℃, solidify 10min, then the solid gel film is washed 12h in the running water that flows, soak with deionized water again, with the solid gel film that cleans up, be immersed in the glycerine water solution that certain density plasticiser is weight 20% concentration, temperature remains on 26 ℃, plasticizing 10min, take out, be tiled on the clean glass plate, natural drying, obtain bacteria cellulose haemodialysis membrane sample;
The 5th step, the bacteria cellulose hemodialysis membrane of gained is tested by SEM sign and film properties, estimate the requirement of whether satisfying haemodialysis; The bacteria cellulose hemodialysis membrane that described SEM characterizes is abundant swelling in deionized water first, then through liquid nitrogen frozen, brittle failure, test behind the metal spraying, Fig. 2 is the cross section metal spraying of freezing brittle failure of the prepared bacteria cellulose haemodialysis of the present embodiment membrane sample SEM figure after by 1500 times of amplifications of SEM, Fig. 3 is that the sample surfaces metal spraying of the prepared bacteria cellulose hemodialysis membrane of present embodiment is by SEM 10, SEM figure after 000 times of amplification, can find out this haemodialysis membrane sample cross section and the surperficial smooth structure of densification that all presents after amplifying, not have obvious hole to exist; Described film properties test comprises hot strength test, the test of water ultrafiltration rate, the test of bovine serum albumin rejection, the test of urea dialysis permeability and the test of cobalamin dialysis permeability, and is specific as follows:
1) hot strength test: the haemodialysis membrane sample of preparation is cut into the strip batten of about 5mm * 40mm, tests with the microcomputer controlled electronic universal tensile testing machine, draw speed is 20mmmin
-1, test clip is apart from being 20mm, recording hot strength is 32.8MPa;
2) water ultrafiltration rate test: use deionized water, utilize the ultrafiltration cup to carry out ultrafiltration under 0.1MPa the haemodialysis membrane sample for preparing, recording the water ultrafiltration rate is 23.0mLm
-2H
-1MmHg
-1
3) bovine serum albumin rejection test: working concentration is 1.0mgmL
-1BSA solution, with the preparation the haemodialysis membrane sample under 0.1MPa, utilize the ultrafiltration cup to carry out ultrafiltration, recording the bovine serum albumin rejection is 96.3%;
4) urea dialysis permeability test: with the hemodialysis membrane specimen holder of preparation in the middle of osmotic cell, on one side osmotic cell adds 0.1mgmL
-1Urea liquid, another side adds deionized water, and whole osmotic cell is put into water-bath, and constant temperature keeps 37 ℃, and recording urea dialysis permeability is 166 * 10
4Cmmin
-1
5) Cobastab
12Dialysis permeability test: with the hemodialysis membrane specimen holder of preparation in the middle of osmotic cell, on one side osmotic cell adds 0.05mgmL
-1Cobastab
12Solution, another side adds deionized water, with black plastic film osmotic cell is wrapped up, and whole osmotic cell is put into water-bath, and constant temperature keeps 37 ℃, records Cobastab
12The dialysis permeability is 73 * 10
4Cmmin
-1
Embodiment 4
In conjunction with Fig. 1, standby bacteria cellulose film hemodialysis membrane of the present invention may further comprise the steps:
The first step, bacteria cellulose preliminary treatment: get a certain amount of bacteria cellulose powder and cross 150 purpose sieves, the powder that sieves out is soaked in 9% the NaOH solution, after stirring 3h under the room temperature, vacuum filtration, use the deionized water cyclic washing, be neutrality to cleaning solution till, use again soaked in absolute ethyl alcohol 3 times, each 3h that keeps, it is dry to put at last vacuum drying chamber, and 80 ℃ of baking temperatures are dried to till the powder constant weight;
Second step, the preparation of LiCl/DMAC dissolution system: the analytically pure LiCl particle of certain mass is put into air dry oven, in 150 ℃ of lower oven dry 24h, LiCl powder and a certain amount of DMAC solvent and at room temperature stirring with oven dry, be mixed with the LiCl/DMAC solution of weight 8% concentration, the solution clear, airtight preservation;
The 3rd step, the dissolving of bacteria cellulose powder: will activate good bacteria cellulose powder, and put into the LiCl/DMAC solution that has prepared, and stir 3 hours in 100 ℃ of lower magnetic forces, and be mixed with the cellulose solution of weight 2% concentration.Put into 4 ℃ of refrigerator standing and defoaming 48h, whole process bottle sealing after being cooled to room temperature;
In the 4th step, the preparation of bacteria cellulose hemodialysis membrane: the cellulose solution of clear is poured into scrapes on the mould machine, adjusting the scraper height is 450 μ m, and knifing speed is transferred to 0.5mmin
-1To scrape immediately lamina membranacea after knifing finishes and put into the DMAC aqueous solution that coagulating bath is weight 20% concentration, temperature remains on 10 ℃, solidify 10min, then the solid gel film is washed 12h in the running water that flows, soak with deionized water again, with the solid gel film that cleans up, be immersed in the glycerine water solution that certain density plasticiser is weight 10% concentration, temperature remains on 26 ℃, plasticizing 10min, take out, be tiled on the clean glass plate, natural drying, obtain bacteria cellulose haemodialysis membrane sample;
The 5th step, the bacteria cellulose hemodialysis membrane of gained is tested by SEM sign and film properties, estimate the requirement of whether satisfying haemodialysis; The bacteria cellulose hemodialysis membrane that described SEM characterizes is abundant swelling in deionized water first, then tests behind liquid nitrogen frozen, brittle failure, metal spraying; Described film properties test comprises hot strength test, the test of water ultrafiltration rate, the test of bovine serum albumin rejection, the test of urea dialysis permeability and the test of cobalamin dialysis permeability, and is specific as follows:
1) hot strength test: the haemodialysis membrane sample of preparation is cut into the strip batten of about 5mm * 40mm, tests with the microcomputer controlled electronic universal tensile testing machine, draw speed is 20mmmin
-1, test clip is apart from being 20mm, recording hot strength is 28.1MPa;
2) water ultrafiltration rate test: use deionized water, utilize the ultrafiltration cup to carry out ultrafiltration under 0.1MPa the haemodialysis membrane sample for preparing, recording the water ultrafiltration rate is 21.0mLm
-2H
-1MmHg
-1
3) bovine serum albumin rejection test: working concentration is 1.0mgmL
-1BSA solution, with the preparation the haemodialysis membrane sample under 0.1MPa, utilize the ultrafiltration cup to carry out ultrafiltration, recording the bovine serum albumin rejection is 96.0%;
4) urea dialysis permeability test: with the hemodialysis membrane specimen holder of preparation in the middle of osmotic cell, on one side osmotic cell adds 0.1mgmL
-1Urea liquid, another side adds deionized water, and whole osmotic cell is put into water-bath, and constant temperature keeps 37 ℃, and recording urea dialysis permeability is 168 * 10
4Cmmin
-1
5) Cobastab
12Dialysis permeability test: with the hemodialysis membrane specimen holder of preparation in the middle of osmotic cell, on one side osmotic cell adds 0.05mgmL
-1Cobastab
12Solution, another side adds deionized water, with black plastic film osmotic cell is wrapped up, and whole osmotic cell is put into water-bath, and constant temperature keeps 37 ℃, records Cobastab
12The dialysis permeability is 75 * 10
4Cmmin
-1
The water flux ability of water ultrafiltration rate reflection film in the hemodialysis membrane dialysis procedure, high-throughout dialysis membrane can be removed unnecessary moisture and middle low-molecular-weight noxious material in the body better; The uremia noxious material of low molecular mass and medium molecule quality is such as urea, uric acid and β in the dialysis procedure
2-microglobulin (11,800Da) need to remove, in order to characterize the regenerated bacteria cellulose membrane to the removing ability of little molecule and medium molecule material, with urea (molecular weight 60) and Cobastab
12Be little molecule and middle molecular substances representative, test regenerated bacteria cellulose membrane is to its dialysis permeability; And molecular weight is 66, the albumin of 000Da is essential the reservation in dialysis procedure, for whether the regenerated bacteria cellulose membrane that characterizes preparation satisfies requirement as hemodialysis membrane, with bovine serum albumin (67,000Da) for characterizing material, ultrafiltration under 0.1MPa, test regenerated bacteria cellulose membrane is to the rejection of bovine serum albumin.
Performance parameter by the prepared hemodialysis membrane of embodiment 1～embodiment 4 is as shown in table 1:
Table 1
By table 1 data as can be known, the bacteria cellulose hemodialysis membrane that is obtained by this preparation method has reached the ultrafiltration level of during high flux hemodialysis device, i.e. water ultrafiltration rate (UFR) 〉=20mLm
-2H
-1MmHg
-1, also meet haemodialysis film water ultrafiltration rate and be generally 10～50mLm
-2H
-1MmHg
-1Requirement.Each dialysis membrane so can guarantee that albumin is difficult for losing in the blood, satisfies the basic demand of hemodialysis membrane to the rejection of bovine serum albumin 〉=96%.Prepared bacteria cellulose hemodialysis membrane has higher dialysis permeability to urea, and its value is higher than the regenerated cellulose film of market sale to the dialysis permeability (100 * 10 of urea
4Cmmin
-1).The bacteria cellulose hemodialysis membrane is to Cobastab
12The dialysis permeability also higher, than the regenerated cellulose hemodialysis membrane of market sale to Cobastab
12Dialysis permeability (20 * 10
4Cmmin
-1) height.
The present invention is take bacteria cellulose as raw material, make renewable cellulose membrane with the immersion precipitation phase inversion, can be used as a kind of novel hemodialysis film for the treatment of acute or chronic renal failure uses, compare it to have a chemical purity height, good biocompatibility, mechanical strength strong with traditional dialysis membrane, the advantages such as the water ultrafiltration rate is larger, and preparation process is simple, green, gentle, controlled, is suitable for the suitability for industrialized production of the hemodialysis membrane of different demands.
Claims (10)
1. bacteria cellulose hemodialysis membrane is characterized in that this hemodialysis membrane by the bacteria cellulose preparation and get, and this hemodialysis membrane is the water white transparency shape, has densification, uniform microstructure; The hot strength of described hemodialysis membrane is 28.1MPa～41.4Mpa, water ultrafiltration rate UFR 〉=20mLm
-2H
-1MmHg
-1, bovine serum albumin rejection 〉=96%, urea dialysis permeability 〉=100 * 10
4Cmmin
-1, Cobastab
12Dialysis permeability 〉=20 * 10
4Cmmin
-1, above performance parameter all satisfies the requirement of haemodialysis.
2. bacteria cellulose hemodialysis membrane according to claim 1, it is characterized in that: the water ultrafiltration rate UFR of described hemodialysis membrane is 20.1mLm
-2H
-1MmHg
-1～23.0mLm
-2H
-1MmHg
-1
3. bacteria cellulose hemodialysis membrane according to claim 1, it is characterized in that: the bovine serum albumin rejection of described hemodialysis membrane is 96.0%～98.5%.
4. bacteria cellulose hemodialysis membrane according to claim 1, it is characterized in that: the urea dialysis permeability of described hemodialysis membrane is 118 * 10
4Cmmin
-1～168 * 10
4Cmmin
-1
5. bacteria cellulose hemodialysis membrane according to claim 1 is characterized in that: the Cobastab of described hemodialysis membrane
12The dialysis permeability is 60 * 10
4Cmmin
-1～75 * 10
4Cmmin
-1
6. the method for preparing bacteria cellulose hemodialysis membrane claimed in claim 1 is characterized in that may further comprise the steps:
The first step, the bacteria cellulose preliminary treatment: the NaOH solution that bacteria cellulose is soaked in weight 3%～9% concentration also stirs, and is then extremely neutral with the deionized water washing, uses soaked in absolute ethyl alcohol again, dries at last;
Second step, the preparation of LiCl/DMAC dissolution system: the LiCl powder is put into air dry oven, in 80～150 ℃ of lower oven dry, then be mixed with the LiCl/DMAC solution of weight 8% concentration with the DMAC solvent, airtight preservation;
The 3rd step, the dissolving of bacteria cellulose powder: with the pretreated bacteria cellulose of the first step, mix with the LiCl/DMAC solution of second step preparation, add the bacterial cellulose solution that thermal agitation is configured to weight 2.0%～3.0% concentration, cooling after the bacteria cellulose dissolving, the refrigerator standing and defoaming;
In the 4th step, the preparation of bacteria cellulose hemodialysis membrane: the bacterial cellulose solution after the processing of the 3rd step is poured on the knifing machine, and adjusting the scraper height is 450 μ m, and knifing speed is 0.5mmin
-1Carry out knifing, will scrape immediately after knifing finishes in the template immersion coagulating bath and solidify, get the solid gel film, this solid gel film is washed with running water, soak with deionized water again; The solid gel film that cleans up is soaked in the plasticiser plastifies, then be tiled on the clean glass plate and dry under natural environment, obtain bacteria cellulose haemodialysis membrane sample;
The 5th step, the bacteria cellulose haemodialysis membrane sample of gained is characterized by SEM and the film properties test, estimate the requirement of whether satisfying haemodialysis, if do not satisfy, adjust preparation condition according to test result and continue to prepare the bacteria cellulose hemodialysis membrane according to the method in the first step～the 4th step; The preparation condition of wherein adjusting comprises the concentration of the composition of preprocessing process, the solution concentration after the bacteria cellulose dissolving, coagulating bath of bacteria cellulose powder and concentration, setting temperature, plasticiser.
7. the preparation method of bacteria cellulose hemodialysis membrane according to claim 6, it is characterized in that: coagulating bath is the DMAC aqueous solution of 10～26 ℃ of temperature, weight 20～40% concentration described in the 4th step, perhaps the ethanolic solution of 4 ℃ of temperature, weight 95% concentration.
8. the preparation method of bacteria cellulose hemodialysis membrane according to claim 6 is characterized in that: the plasticiser described in the 4th step is the glycerine water solution of 26 ℃ of temperature, weight 10%～20% concentration.
9. the preparation method of bacteria cellulose hemodialysis membrane according to claim 6 is characterized in that: the haemodialysis membrane sample that described SEM of the 5th step characterizes is abundant swelling in deionized water first, then tests behind liquid nitrogen frozen, brittle failure, metal spraying.
10. the preparation method of bacteria cellulose hemodialysis membrane according to claim 6, it is characterized in that: the 5th step, described film properties test comprised hot strength test, the test of water ultrafiltration rate, the test of bovine serum albumin rejection, the test of urea dialysis permeability and the test of cobalamin dialysis permeability, and is specific as follows:
1) hot strength test: the haemodialysis membrane sample of preparation is tested with the microcomputer controlled electronic universal tensile testing machine;
2) water ultrafiltration rate test: use deionized water, under 0.1MPa, utilize the ultrafiltration cup to carry out ultrafiltration the haemodialysis membrane sample for preparing;
3) bovine serum albumin rejection test: working concentration is 1.0mgmL
-1BSA solution, with the preparation the haemodialysis membrane sample under 0.1MPa, utilize the ultrafiltration cup to carry out ultrafiltration;
4) urea dialysis permeability test: with the hemodialysis membrane specimen holder of preparation in the middle of osmotic cell, on one side osmotic cell adds 0.1mgmL
-1Urea liquid, another side adds deionized water, and whole osmotic cell is put into water-bath, and constant temperature keeps 37 ℃ to be tested;
5) Cobastab
12Dialysis permeability test: with the hemodialysis membrane specimen holder of preparation in the middle of osmotic cell, on one side osmotic cell adds 0.05mgmL
-1Cobastab
12Solution, another side adds deionized water, with black plastic film osmotic cell is wrapped up, and whole osmotic cell is put into water-bath, and constant temperature keeps 37 ℃ to be tested.
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