CN111875742A - Preparation method of hydrophilic bacterial cellulose, hydrophilic bacterial cellulose and application - Google Patents
Preparation method of hydrophilic bacterial cellulose, hydrophilic bacterial cellulose and application Download PDFInfo
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- CN111875742A CN111875742A CN201910521623.6A CN201910521623A CN111875742A CN 111875742 A CN111875742 A CN 111875742A CN 201910521623 A CN201910521623 A CN 201910521623A CN 111875742 A CN111875742 A CN 111875742A
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- 229920002749 Bacterial cellulose Polymers 0.000 title claims abstract description 129
- 239000005016 bacterial cellulose Substances 0.000 title claims abstract description 129
- 238000002360 preparation method Methods 0.000 title claims abstract description 16
- PQUXFUBNSYCQAL-UHFFFAOYSA-N 1-(2,3-difluorophenyl)ethanone Chemical compound CC(=O)C1=CC=CC(F)=C1F PQUXFUBNSYCQAL-UHFFFAOYSA-N 0.000 claims abstract description 23
- 229940047670 sodium acrylate Drugs 0.000 claims abstract description 23
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 claims description 72
- 229910052757 nitrogen Inorganic materials 0.000 claims description 34
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 25
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims description 24
- ZMANZCXQSJIPKH-UHFFFAOYSA-N Triethylamine Chemical compound CCN(CC)CC ZMANZCXQSJIPKH-UHFFFAOYSA-N 0.000 claims description 24
- CIWBSHSKHKDKBQ-JLAZNSOCSA-N Ascorbic acid Chemical compound OC[C@H](O)[C@H]1OC(=O)C(O)=C1O CIWBSHSKHKDKBQ-JLAZNSOCSA-N 0.000 claims description 16
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 claims description 16
- 238000003756 stirring Methods 0.000 claims description 16
- 239000006185 dispersion Substances 0.000 claims description 14
- 239000007788 liquid Substances 0.000 claims description 14
- 238000006243 chemical reaction Methods 0.000 claims description 11
- 239000011261 inert gas Substances 0.000 claims description 9
- YOCIJWAHRAJQFT-UHFFFAOYSA-N 2-bromo-2-methylpropanoyl bromide Chemical compound CC(C)(Br)C(Br)=O YOCIJWAHRAJQFT-UHFFFAOYSA-N 0.000 claims description 8
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- 235000010323 ascorbic acid Nutrition 0.000 claims description 8
- 239000011668 ascorbic acid Substances 0.000 claims description 8
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- 239000008367 deionised water Substances 0.000 claims description 8
- 229910021641 deionized water Inorganic materials 0.000 claims description 8
- GBMDVOWEEQVZKZ-UHFFFAOYSA-N methanol;hydrate Chemical compound O.OC GBMDVOWEEQVZKZ-UHFFFAOYSA-N 0.000 claims description 8
- 239000011259 mixed solution Substances 0.000 claims description 8
- 239000011780 sodium chloride Substances 0.000 claims description 8
- 238000005406 washing Methods 0.000 claims description 8
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- 239000003519 biomedical and dental material Substances 0.000 claims description 4
- 229940030225 antihemorrhagics Drugs 0.000 claims description 2
- 239000002874 hemostatic agent Substances 0.000 claims description 2
- 238000010560 atom transfer radical polymerization reaction Methods 0.000 abstract description 20
- 230000004048 modification Effects 0.000 abstract description 13
- 238000012986 modification Methods 0.000 abstract description 13
- 239000000178 monomer Substances 0.000 abstract description 10
- 238000007385 chemical modification Methods 0.000 abstract description 5
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- 238000000576 coating method Methods 0.000 abstract description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 20
- 238000012360 testing method Methods 0.000 description 11
- 229920002678 cellulose Polymers 0.000 description 8
- 239000001913 cellulose Substances 0.000 description 8
- 238000010521 absorption reaction Methods 0.000 description 7
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- 230000000694 effects Effects 0.000 description 5
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- 238000006297 dehydration reaction Methods 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 238000001878 scanning electron micrograph Methods 0.000 description 4
- 241000589220 Acetobacter Species 0.000 description 3
- 102000015081 Blood Coagulation Factors Human genes 0.000 description 3
- 108010039209 Blood Coagulation Factors Proteins 0.000 description 3
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- 108010049003 Fibrinogen Proteins 0.000 description 3
- 230000001580 bacterial effect Effects 0.000 description 3
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- 238000002156 mixing Methods 0.000 description 3
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- 241000589158 Agrobacterium Species 0.000 description 2
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- 230000015572 biosynthetic process Effects 0.000 description 2
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- 238000011160 research Methods 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- 238000012546 transfer Methods 0.000 description 2
- 235000002837 Acetobacter xylinum Nutrition 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-M Acrylate Chemical compound [O-]C(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-M 0.000 description 1
- 241000032681 Gluconacetobacter Species 0.000 description 1
- 229920002488 Hemicellulose Polymers 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- 241001136169 Komagataeibacter xylinus Species 0.000 description 1
- CERQOIWHTDAKMF-UHFFFAOYSA-M Methacrylate Chemical compound CC(=C)C([O-])=O CERQOIWHTDAKMF-UHFFFAOYSA-M 0.000 description 1
- 229920001410 Microfiber Polymers 0.000 description 1
- CKUAXEQHGKSLHN-UHFFFAOYSA-N [C].[N] Chemical compound [C].[N] CKUAXEQHGKSLHN-UHFFFAOYSA-N 0.000 description 1
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- CREMABGTGYGIQB-UHFFFAOYSA-N carbon carbon Chemical compound C.C CREMABGTGYGIQB-UHFFFAOYSA-N 0.000 description 1
- 239000011203 carbon fibre reinforced carbon Substances 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000005518 electrochemistry Effects 0.000 description 1
- 238000007720 emulsion polymerization reaction Methods 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 238000000855 fermentation Methods 0.000 description 1
- 230000004151 fermentation Effects 0.000 description 1
- 235000013305 food Nutrition 0.000 description 1
- 238000010528 free radical solution polymerization reaction Methods 0.000 description 1
- 229920000578 graft copolymer Polymers 0.000 description 1
- 150000004820 halides Chemical class 0.000 description 1
- 125000005843 halogen group Chemical group 0.000 description 1
- 230000002439 hemostatic effect Effects 0.000 description 1
- 229920001519 homopolymer Polymers 0.000 description 1
- 239000000017 hydrogel Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
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- 239000003999 initiator Substances 0.000 description 1
- 229920005610 lignin Polymers 0.000 description 1
- 238000010550 living polymerization reaction Methods 0.000 description 1
- YQCIWBXEVYWRCW-UHFFFAOYSA-N methane;sulfane Chemical compound C.S YQCIWBXEVYWRCW-UHFFFAOYSA-N 0.000 description 1
- 239000003658 microfiber Substances 0.000 description 1
- 238000002715 modification method Methods 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
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- 230000035484 reaction time Effects 0.000 description 1
- 238000006479 redox reaction Methods 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 241000894007 species Species 0.000 description 1
- 229910052723 transition metal Inorganic materials 0.000 description 1
- 150000003624 transition metals Chemical class 0.000 description 1
Images
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F251/00—Macromolecular compounds obtained by polymerising monomers on to polysaccharides or derivatives thereof
- C08F251/02—Macromolecular compounds obtained by polymerising monomers on to polysaccharides or derivatives thereof on to cellulose or derivatives thereof
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L15/00—Chemical aspects of, or use of materials for, bandages, dressings or absorbent pads
- A61L15/16—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons
- A61L15/22—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons containing macromolecular materials
- A61L15/24—Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds; Derivatives thereof
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L15/00—Chemical aspects of, or use of materials for, bandages, dressings or absorbent pads
- A61L15/16—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons
- A61L15/42—Use of materials characterised by their function or physical properties
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L15/00—Chemical aspects of, or use of materials for, bandages, dressings or absorbent pads
- A61L15/16—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons
- A61L15/42—Use of materials characterised by their function or physical properties
- A61L15/62—Compostable, hydrosoluble or hydrodegradable materials
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L24/00—Surgical adhesives or cements; Adhesives for colostomy devices
- A61L24/001—Use of materials characterised by their function or physical properties
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L24/00—Surgical adhesives or cements; Adhesives for colostomy devices
- A61L24/001—Use of materials characterised by their function or physical properties
- A61L24/0042—Materials resorbable by the body
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L24/00—Surgical adhesives or cements; Adhesives for colostomy devices
- A61L24/04—Surgical adhesives or cements; Adhesives for colostomy devices containing macromolecular materials
- A61L24/06—Surgical adhesives or cements; Adhesives for colostomy devices containing macromolecular materials obtained by reactions only involving carbon-to-carbon unsaturated bonds
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L2400/00—Materials characterised by their function or physical properties
- A61L2400/04—Materials for stopping bleeding
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F2438/00—Living radical polymerisation
- C08F2438/01—Atom Transfer Radical Polymerization [ATRP] or reverse ATRP
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Abstract
The application discloses a preparation method of hydrophilic bacterial cellulose, hydrophilic bacterial cellulose and application, the preparation method is characterized in that chemical modification is carried out on the surface of the bacterial cellulose by utilizing an Atom Transfer Radical Polymerization (ATRP) technology, a sodium acrylate monomer is uniformly grafted and polymerized onto the bacterial cellulose, successful surface chemical modification of the bacterial cellulose is realized, the modified bacterial cellulose has excellent hydrophilic performance, and the hydrophilicity can still be maintained along with the time lapse. Compared with the traditional modification of directly coating a hydrophilic layer, the ATRP technology can uniformly, effectively and accurately modify.
Description
Technical Field
The invention relates to the technical field of biomedical material modification, and in particular relates to a preparation method of hydrophilic bacterial cellulose, hydrophilic bacterial cellulose and application of the hydrophilic bacterial cellulose.
Background
Bacterial Cellulose (BC) is natural cellulose containing no impurities, and is a general name of cellulose synthesized by some microorganism in the genera Acetobacter (Acetobacter), Agrobacterium (Agrobacterium), Rhizobium (Rhizobium), Sarcina (Sarcina), and the like. Gluconacetobacter in Acetobacter has high cellulose productivity and is confirmed to be a model strain for researching cellulose synthesis, crystallization process and structural properties. Bacterial cellulose possesses the following characteristics: (1) has high purity and crystallinity. Compared with plant cellulose, the bacterial cellulose does not contain impurities such as hemicellulose, lignin and the like, and exists in the form of 100% cellulose. (2) Fine network structure. The bacterial cellulose fiber is a 40-60 nm thick fiber bundle formed by combining microfibers with diameters of 3-4 nm, and the fibers are mutually interwoven to form a developed hyperfine network structure. The diameter of the bacterial cellulose produced by the acetobacter xylinum is between 0.01 and 0.1 mu m, and the bacterial cellulose is a natural nano-grade material. Whereas plant cellulose has a diameter of about 10 μm, which is hundreds times larger than that of bacterial cellulose. (3) The controllability during synthesis. The structure and properties of the cellulose obtained vary with the fermentation conditions. (4) Degradability and recyclability. Under natural conditions, the microorganisms can degrade cellulose into micromolecular sugar, and environmental pollution can not be caused. (5) Good hydrophilicity and air permeability. The bacterial cellulose has a large number of hydrophilic groups inside, and the molecules and the inside of the bacterial cellulose are connected with each other through hydrogen bonds, so that the bacterial cellulose is determined to be hydrogel, wherein the bound water accounts for the most part, and the free water accounts for only 10 percent. (6) High tensile strength and young's modulus. After the bacterial cellulose is dried, the Young modulus can reach 10MPa, which is 4 times of that of the synthetic cellulose.
Because bacterial cellulose has many unique properties such as fine network structure, high mechanical strength, high water absorption and retention performance, good biocompatibility and biodegradability, in recent years, intensive research on bacterial cellulose mainly focuses on the fields of biomedicine, electrochemistry and optics, food packaging and the like, and is one of the hot spots of international biomaterial research. However, in some specific biomaterial designs, such as dressings, hemostats, etc., these require the material itself to satisfy strong water absorption capability to rapidly and efficiently absorb the biological fluid and concentrate the blood in the bleeding area (increase the concentration of blood coagulation factors and fibrinogen, and accelerate hemostasis). Although bacterial cellulose has certain hydrophilic performance, in order to improve the performance of the dressing or the hemostatic prepared on the basis of the bacterial cellulose, the enhancement of the hydrophilic performance of the bacterial cellulose is a field worth discussing.
Atom Transfer Radical Polymerization (ATRP) is a new living polymerization reaction. As with atom transfer radical addition reactions, in atom transfer radical polymerization, two different catalytic processes can form carbon-carbon, carbon-sulfur, carbon-nitrogen, etc. bonds. The reaction system takes organic halide as an initiator and a transition metal complex as a halogen atom carrier, and reversible dynamic equilibrium is established between active species and dormant species through redox reaction, so that the control of polymerization reaction is realized. The advantages are that: (1) the monomers suitable for ATRP are more in variety: most monomers such as methacrylate, acrylate, styrene, and charge transfer complexes can be smoothly ATRP, and living homopolymers, block and graft copolymers have been successfully prepared; (2) gradient copolymers can be synthesized: the monomer with higher activity enters the polymer at the initial stage of polymerization, the concentration of the monomer with higher activity is reduced along with the reaction, and the monomer with lower activity enters the polymer chain more, so that a gradient copolymer with the comonomer changing in gradient along with the prolonging of time is formed; (3) suitable for use in a wide variety of industrial polymerization processes, such as bulk polymerization, solution polymerization, and emulsion polymerization; (4) the polymerized monomer is uniform and controllable, and the regulation and control of the performance can be indirectly realized.
Disclosure of Invention
The invention aims to overcome at least one defect of the prior art, and provides a preparation method of hydrophilic bacterial cellulose, wherein the preparation method utilizes an Atom Transfer Radical Polymerization (ATRP) technology to carry out chemical modification on the surface of the bacterial cellulose, and sodium acrylate monomers are uniformly polymerized onto the bacterial cellulose, and compared with the traditional modification of directly coating a hydrophilic layer or blending modification, the ATRP technology can carry out modification uniformly, effectively and accurately.
The invention also aims to provide the hydrophilic bacterial cellulose prepared by the ATRP technology, and the contact angle of the prepared hydrophilic bacterial cellulose can reach 0 degree, and the hydrophilic bacterial cellulose has strong hydrophilic and water-absorbing properties.
The technical scheme adopted by the invention is as follows:
a preparation method of hydrophilic bacterial cellulose comprises the following steps:
s1, dehydrating the bacterial cellulose dispersion liquid with the mass concentration of 0.55-0.6%, weighing 5-10 g of the bacterial cellulose dispersion liquid, adding the 5-10 g of the bacterial cellulose dispersion liquid into a flask, adding 40-60 ml of N, N-dimethylformamide, keeping the inert gas atmosphere for 15-30 min, adding 3-5 ml of triethylamine, dropwise adding 3-5 ml of 2-bromoisobutyryl bromide under the ice bath condition, recovering to room temperature, continuing to react for 12-24 h at the room temperature, centrifuging, continuing to wash with N, N-dimethylformamide, and centrifuging to obtain brominated bacterial cellulose;
s2, adding 1-2 g of sodium acrylate, 4-5 g of brominated bacterial cellulose, 1-2 g of sodium chloride, 25-35 ml of methanol, 20-40 ml of deionized water, 15-30 mu l N, N, N' -pentamethyldiethylenetriamine into a flask, stirring for 15-60 min under the protection of inert gas, then adding 0.03-0.05 g of copper bromide and 45-55 mg of ascorbic acid, stirring for 15-60 min under the protection of inert gas, placing the flask in an oil bath at 75-90 ℃, reacting for 12-48 h, centrifuging after the reaction is finished, and washing with a methanol-water mixed solution to obtain the hydrophilic bacterial cellulose modified by the sodium acrylate.
The method utilizes an Atom Transfer Radical Polymerization (ATRP) technology to carry out chemical modification on the surface of the bacterial cellulose, uniformly polymerizes sodium acrylate monomers on the bacterial cellulose, regulates and controls reaction time, temperature and monomer amount to realize successful surface chemical modification on the bacterial cellulose, and the modified bacterial cellulose has excellent hydrophilic performance (a contact angle can reach 0 degree), and can still maintain hydrophilicity along with the passage of time. Compared with the traditional modification of directly coating a hydrophilic layer, the ATRP technology can uniformly, effectively and accurately modify.
Preferably, step S1 is: dehydrating bacterial cellulose dispersion liquid with the mass concentration of 0.55-0.6%, weighing 8-10 g of the bacterial cellulose dispersion liquid, adding the bacterial cellulose dispersion liquid into a single-mouth round-bottom flask, adding 40-60 ml of N, N-dimethylformamide, keeping the atmosphere of N2, adding 3-5 ml of triethylamine, dropwise adding 3-5 ml of 2-bromoisobutyryl bromide under the ice bath condition, recovering to room temperature, continuing to react for 12-24 hours at the normal temperature, centrifuging, continuing to wash with N, N-dimethylformamide, and centrifuging to obtain brominated bacterial cellulose.
Preferably, step S2 is: adding 1-2 g of sodium acrylate, 4-5 g of brominated bacterial cellulose, 1-2 g of sodium chloride, 25-35 ml of methanol, 25-35 ml of deionized water, 15-30 mu l N, N, N' -pentamethyldiethylenetriamine and N2 into an eggplant-shaped bottle, stirring for 15-45 min under protection, then adding 0.03-0.05 g of copper bromide and 45-55 mg of ascorbic acid, stirring for 15-45 min under protection of inert gas, placing the eggplant-shaped bottle into an oil bath at 75-90 ℃, reacting for 12-48 h, centrifuging after reaction, and washing with a methanol-water mixed solution to obtain the sodium acrylate modified hydrophilic bacterial cellulose.
The hydrophilic bacterial cellulose comprises bacterial cellulose and a sodium polyacrylate layer which is grafted and coated on the surface of the bacterial cellulose.
The hydrophilic bacterial cellulose obtained by chemically modifying the surface of the bacterial cellulose by utilizing the ATRP technology is grafted with a sodium polyacrylate layer on the surface of the bacterial cellulose, the bacterial cellulose has a fine network structure, high mechanical strength, high water absorption and water retention performance, good biocompatibility and excellent biodegradability, the bacterial cellulose has more excellent hydrophilic characteristic after being grafted with the sodium polyacrylate layer, and has strong absorption effect on water, and biological seepage and blood in a bleeding area can be quickly and efficiently absorbed (the concentration of blood coagulation factors and fibrinogen is promoted, and hemostasis is accelerated).
Preferably, the contact angle of the hydrophilic bacterial cellulose is 0 °. The contact angle of the hydrophilic bacterial cellulose obtained by the ATRP technology can reach 0 degree.
The application also discloses application of the hydrophilic bacterial cellulose in preparation of biomedical materials.
Preferably, the biomedical material is a dressing or a hemostatic agent.
Compared with the prior art, the invention has the beneficial effects that: according to the method, the surface of the bacterial cellulose is chemically modified by utilizing an Atom Transfer Radical Polymerization (ATRP) technology, and compared with the traditional modification or blending modification of directly coating a hydrophilic layer, the ATRP technology can be used for uniformly, effectively and accurately modifying; the modified hydrophilic bacterial cellulose not only retains the fine network structure, higher mechanical strength, higher water absorption and retention performance, good biocompatibility and excellent biodegradability of the bacterial cellulose, but also has excellent hydrophilic property, has strong absorption effect on water, and can quickly and efficiently absorb biological seepage and concentrate blood in bleeding areas (the concentration of blood coagulation factors and fibrinogen is improved, and the hemostasis is accelerated); according to the modification method, the sodium polyacrylate is grafted to the bacterial cellulose, compared with the traditional modification of directly coating a hydrophilic layer or the blending modification, the bacterial cellulose subjected to chemical reaction grafting modification is more stable in performance than the bacterial cellulose subjected to physical adsorption, and the modified bacterial cellulose can still maintain strong hydrophilicity along with the time lapse.
Drawings
FIG. 1 is a SEM image of hydrophilic bacterial cellulose in example 1.
FIG. 2 is a SEM image of bacterial cellulose of example 1.
FIG. 3 is a scanning electron microscope element mapping of the hydrophilic bacterial cellulose in example 1.
FIG. 4 is a contact angle test chart of the bacterial cellulose/hydrophilic bacterial cellulose in example 1.
Detailed Description
The drawings are only for purposes of illustration and are not to be construed as limiting the invention. For a better understanding of the following embodiments, certain features of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.
Example 1
A preparation method of hydrophilic bacterial cellulose comprises the following steps:
s1, completely dehydrating the bacterial cellulose dispersion liquid with the mass concentration of 0.6% (through N, N-dimethylformamide multiple-dispersing centrifugal dehydration), weighing 8g, adding the weighed mass into a 100ml single-mouth round-bottom flask, adding 40ml of N, N-dimethylformamide, keeping the atmosphere of inert gas, adding 3.2ml of triethylamine, dropwise adding 4ml of 2-bromoisobutyryl bromide under the ice bath condition, recovering to room temperature, continuing to react for 12h at normal temperature, centrifuging, continuing to wash with N, N-dimethylformamide, and centrifuging to obtain brominated bacterial cellulose (a small amount of N, N-dimethylformamide remains);
s2, adding 1.5g of sodium acrylate, 4.5g of brominated bacterial fibers obtained in the step S1, 1g of sodium chloride, 30mL of methanol, 30mL of deionized water, 20 mu l N, N, N' -pentamethyldiethylenetriamine into an eggplant-shaped bottle, stirring for 30min under the protection of nitrogen, then adding 0.03g of copper bromide and 50mg of ascorbic acid, stirring for 30min under the protection of nitrogen, placing the flask in an oil bath at 75-90 ℃, reacting for 24h, centrifuging after the reaction is finished, and washing with a methanol-water mixed solution to obtain the hydrophilic bacterial cellulose modified by the sodium acrylate.
Example 2
A preparation method of hydrophilic bacterial cellulose comprises the following steps:
s1, completely dehydrating the bacterial cellulose dispersion liquid with the mass concentration of 0.55% (through N, N-dimethylformamide multiple-dispersing centrifugal dehydration), weighing 9g, adding the weighed 9g into a 100ml single-neck round-bottom flask, adding 60ml of N, N-dimethylformamide, keeping the atmosphere of nitrogen, adding 5ml of triethylamine, dropwise adding 5ml of 2-bromoisobutyryl bromide under an ice bath condition, recovering to room temperature, continuing to react for 12 hours at room temperature, centrifuging, continuing to wash with N, N-dimethylformamide, and centrifuging to obtain brominated bacterial cellulose (a small amount of N, N-dimethylformamide remains);
s2, adding 1g of sodium acrylate, 4g of brominated bacterial fibers prepared in the step S1, 1.5g of sodium chloride, 35mL of methanol, 20mL of deionized water, 15 mu l N, N, N' -pentamethyldiethylenetriamine, stirring for 30min under the protection of nitrogen, then adding 0.03g of copper bromide and 45mg of ascorbic acid, stirring for 30min under the protection of nitrogen, placing the flask in an oil bath at 75-90 ℃, reacting for 24h, centrifuging after the reaction is finished, and washing with a methanol-water mixed solution to obtain the hydrophilic bacterial cellulose modified by the sodium acrylate.
Example 3
A preparation method of hydrophilic bacterial cellulose comprises the following steps:
s1, completely dehydrating the bacterial cellulose dispersion liquid with the mass concentration of 0.6% (through N, N-dimethylformamide multiple-dispersing centrifugal dehydration), weighing 10g, adding the 10g into a 100ml single-neck round-bottom flask, adding 50ml of N, N-dimethylformamide, keeping the nitrogen atmosphere, adding 3ml of triethylamine, dropwise adding 3ml of 2-bromoisobutyryl bromide under the ice bath condition, recovering to room temperature, continuing to react for 18 hours at room temperature, centrifuging, continuing to wash with N, N-dimethylformamide, and centrifuging to obtain brominated bacterial cellulose (a small amount of N, N-dimethylformamide remains);
s2, adding 2g of sodium acrylate, 5g of brominated bacterial cellulose prepared in the step S1, 2g of sodium chloride, 25mL of methanol, 40mL of deionized water, 30 mu l N, N, N' -pentamethyldiethylenetriamine into an eggplant-shaped bottle, stirring for 30min under the protection of nitrogen, then adding 0.05g of copper bromide and 55mg of ascorbic acid, stirring for 30min under the protection of nitrogen, placing the flask in an oil bath at 75-90 ℃, reacting for 24h, centrifuging after the reaction is finished, and washing with a methanol-water mixed solution to obtain the hydrophilic bacterial cellulose modified by the sodium acrylate.
Example 4
A preparation method of hydrophilic bacterial cellulose comprises the following steps:
s1, completely dehydrating the bacterial cellulose dispersion liquid with the mass concentration of 0.6% (through N, N-dimethylformamide multiple-dispersing centrifugal dehydration), weighing 8g, adding the weighed 8g into a 100ml single-mouth round-bottom flask, adding 40ml of N, N-dimethylformamide, keeping the atmosphere of nitrogen, adding 3ml of triethylamine, dropwise adding 4.5ml of 2-bromoisobutyryl bromide under an ice bath condition, recovering to room temperature, continuing to react for 24h at the normal temperature, centrifuging, continuing to wash with N, N-dimethylformamide, and centrifuging to obtain brominated bacterial cellulose (a small amount of N, N-dimethylformamide remains);
s2, adding 1.2g of sodium acrylate, 4.8g of brominated bacterial fibers obtained in the step S1, 2g of sodium chloride, 28mL of methanol, 30mL of deionized water, 20 mu l N, N, N' -pentamethyldiethylenetriamine into an eggplant-shaped bottle, stirring for 30min under the protection of nitrogen, then adding 0.05g of copper bromide and 48mg of ascorbic acid, stirring for 30min under the protection of nitrogen, placing the flask in an oil bath at 75-90 ℃, reacting for 24h, centrifuging after the reaction is finished, and washing with a methanol-water mixed solution to obtain the hydrophilic bacterial cellulose modified by the sodium acrylate.
In order to verify whether the sodium acrylate is successfully grafted to the surface of the bacterial cellulose, a Scanning Electron Microscope (SEM) test is performed on the prepared hydrophilic bacterial cellulose, as shown in fig. 1, the SEM image of the hydrophilic bacterial cellulose prepared in example 1 is shown, and fig. 2 is the SEM image of the bacterial cellulose of example 1, and it can be known from comparing fig. 1 and fig. 2 that the bacterial cellulose is fine and smooth, compared with the bacterial cellulose, the modified hydrophilic bacterial cellulose is thickened, and it is shown that the sodium acrylate is uniformly grafted on the surface of the bacterial cellulose. Fig. 3 is a scanning electron microscope element mapping of modified hydrophilic bacterial cellulose, from which the presence of elemental sodium was seen, at about 2.69% by weight and about 1.66% by atomic percent.
The contact angle tests of the bacterial cellulose and the hydrophilic bacterial cellulose are carried out according to the ISO15989Technical Corrigengdum 1-2007 standard, and the contact angle test results of the examples 1 to 4 are respectively shown in tables 1 to 4. The contact angle test chart of example 1 is shown in fig. 4, wherein a is the contact angle test chart of the bacterial cellulose, and b is the contact angle test chart of the hydrophilic bacterial cellulose modified by sodium acrylate.
Table 1 example 1 contact angle test results
Table 2 example 2 contact angle test results
Table 3 example 3 contact angle test results
Table 4 example 4 contact angle test results
As can be seen from tables 1 to 4, the contact angle comparison between the bacterial cellulose and the modified hydrophilic bacterial cellulose shows that: the contact angle of the hydrophilic bacterial cellulose after the grafting modification of the sodium acrylate is smaller, and the water absorption speed is higher.
The hydrophilic bacterial cellulose can be used for preparing biomedical materials such as dressings and hemostats, and has precious application value.
It should be understood that the above-mentioned embodiments of the present invention are only examples for clearly illustrating the technical solutions of the present invention, and are not intended to limit the specific embodiments of the present invention. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention claims should be included in the protection scope of the present invention claims.
Claims (7)
1. A preparation method of hydrophilic bacterial cellulose is characterized by comprising the following steps:
s1, dehydrating the bacterial cellulose dispersion liquid with the mass concentration of 0.55-0.6%, weighing 5-10 g of the bacterial cellulose dispersion liquid, adding the 5-10 g of the bacterial cellulose dispersion liquid into a flask, adding 40-60 ml of N, N-dimethylformamide, keeping the inert gas atmosphere for 15-30 min, adding 3-5 ml of triethylamine, dropwise adding 3-5 ml of 2-bromoisobutyryl bromide under the ice bath condition, recovering to room temperature, continuing to react for 12-24 h at the room temperature, centrifuging, continuing to wash with N, N-dimethylformamide, and centrifuging to obtain brominated bacterial cellulose;
s2, adding 1-2 g of sodium acrylate, 4-5 g of brominated bacterial cellulose, 1-2 g of sodium chloride, 25-35 ml of methanol, 20-40 ml of deionized water, 15-30 mu l N, N, N' -pentamethyldiethylenetriamine into a flask, stirring for 15-60 min under the protection of inert gas, then adding 0.03-0.05 g of copper bromide and 45-55 mg of ascorbic acid, stirring for 15-60 min under the protection of inert gas, placing the flask in an oil bath at 75-90 ℃, reacting for 12-48 h, centrifuging after the reaction is finished, and washing with a methanol-water mixed solution to obtain the hydrophilic bacterial cellulose modified by the sodium acrylate.
2. The method for preparing hydrophilic bacterial cellulose according to claim 1, wherein step S1 is: dehydrating bacterial cellulose dispersion liquid with mass concentration of 0.55-0.6%, weighing 8-10 g, adding into a single-neck round-bottom flask, adding 40-60 ml of N, N-dimethylformamide, and keeping N2And (3) adding 3-5 ml of triethylamine under an atmosphere, dropwise adding 3-5 ml of 2-bromoisobutyryl bromide under an ice bath condition, recovering to room temperature, continuing to react for 12-24 h at room temperature, centrifuging, continuing to wash with N, N-dimethylformamide, and centrifuging to obtain the brominated bacterial cellulose.
3. The method for preparing hydrophilic bacterial cellulose according to claim 1, wherein step S2 is: adding 1-2 g of sodium acrylate, 4-5 g of brominated bacterial cellulose, 1-2 g of sodium chloride, 25-35 ml of methanol and 25-35 ml of deionized water into an eggplant-shaped bottle,15 to 30. mu.l of N, N, N' -pentamethyldiethylenetriamine, N2Stirring for 15-45 min under protection, then adding 0.03-0.05 g of copper bromide and 45-55 mg of ascorbic acid, stirring for 15-45 min under the protection of inert gas, placing the eggplant-shaped bottle in an oil bath at 75-90 ℃, reacting for 12-48 h, centrifuging after the reaction is finished, and washing with a methanol-water mixed solution to obtain the sodium acrylate modified hydrophilic bacterial cellulose.
4. The hydrophilic bacterial cellulose prepared by the preparation method of any one of claims 1 to 3, which is characterized by comprising bacterial cellulose and a sodium polyacrylate layer grafted and coated on the surface of the bacterial cellulose.
5. The hydrophilic bacterial cellulose according to claim 5, wherein a contact angle of the hydrophilic bacterial cellulose is 0 °.
6. Use of the hydrophilic bacterial cellulose of claim 4 or 5 for the preparation of a biomedical material.
7. The use of claim 6, wherein the biomedical material is a dressing or a hemostatic agent.
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