CN106668954B - A kind of cation-modified absorbable pachymeninx repair materials and the preparation method and application thereof of antibiotic property - Google Patents
A kind of cation-modified absorbable pachymeninx repair materials and the preparation method and application thereof of antibiotic property Download PDFInfo
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- A61L27/00—Materials for grafts or prostheses or for coating grafts or prostheses
- A61L27/50—Materials characterised by their function or physical properties, e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials
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- A61L2300/40—Biologically active materials used in bandages, wound dressings, absorbent pads or medical devices characterised by a specific therapeutic activity or mode of action
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Abstract
The invention belongs to regenerative medicine Material Fields, and in particular to a kind of adsorbable artificial endocranium and the preparation method and application thereof that antibiotic property is cation-modified.The cation-modified endocranium repair materials of the antibiotic property are in double-layer structure, and one layer is the degradable polyester nano fibrous membrane modified through epsilon-polylysine, and another layer is the high molecular material of three-dimensional porous structure.Absorbable endocranium repair materials provided by the invention have excellent antagonistic property, can effective prevention of postoperative intracranial infection, while not only can directly attach but also can suture use, product form and preparation process are simple, Yi Shixian industrialization production.The cation-modified endocranium repair materials of antibiotic property of the present invention are the new medical biomaterials of a kind of structure novel, superior performance, repair field in dura defect and show good application prospect.
Description
Technical field
The invention belongs to regenerative medicine Material Fields, and in particular to a kind of adsorbable artificial that antibiotic property is cation-modified is hard
Meninx and the preparation method and application thereof.
Background technique
Endocranium is one layer of connective tissue being located on the inside of skull and on the outside of brain, is the natural barrier for protecting brain tissue.
The reasons such as open craniocerebral bone injury, metastases and other brainpan illness will cause dura defect, and then lead to cerebrospinal fluid
The generation of leakage.Simultaneously as intracranial infection caused by meningitis etc. is still the common severe complication of post-craniocerebral operation.
The incidence of document report, Postoperative Intracranial Infections is still up to 0.2%~5%.Once postoperative infect, not only greatly increase
The medical expense of patient, serious person will lead to the failure and death of operation.Therefore how effectively to repair dura defect and prevent and treat
Postoperative infection is scientist's urgent problem to be solved of spinal surgery, neurosurgeon and technical field of biological material.
Artificial dura mater made of existing multiple material is just in clinical use at present, and can be divided mainly into two major classes: biology spreads out
Green material and artificial synthesized high molecular material.Bio-derived material mainly have allogeneic human cerebral dura mater and xenogenesis pig/
Ox source pericardium, dermal matrix and the biomembrane prepared using ox tendon type i collagen etc..Artificial synthesized high molecular material is main
It additionally include poly- four including polyesters degradable macromolecule, such as polylactic acid, polyglycolic acid, polycaprolactone and polyurethane
The non-degradables high molecular material such as vinyl fluoride.But it up to the present, is produced in clinic using artificial dura mater made of above-mentioned material
Product all do not have the function of prevention and treatment postoperative infection, cannot fully meet clinical requirement.
Epsilon-polylysine is a kind of homotype monomer-polymer as made of 25-30 lysine polycondensation, generally by microorganism
It is natural fermented to obtain.Due to being rich in amino cation in structure, good bacteriostatic activity is had been shown to have, and catabolite is
One of eight kinds of amino acid needed by human, it is safe and non-toxic, it is known as " auxotype antibacterial agent ", in fields such as medicine, food antiseptics
It has a wide range of applications.Therefore, by antibiotic property cation --- epsilon-polylysine is added in artificial dura mater repair materials, in advance
Phase can make it have excellent anti-infective characteristic after clinical use.
Chinese patent " a kind of the nontoxic dressing of wide spectrum of water dispersible abandonment and preparation method thereof " (patent No.
CN105963762A), disclose a kind of prepare using electrostatic spinning or centrifugal spinning and contain the Antibacterial Constituents such as polylysine
Water-soluble or alcohol soluble high molecular fiber dressing method.Polylysine in the patent is by being mixed directly into macromolecule
Mode in spinning solution is added to dressing fibrous inside, is disadvantageous in that polylysine ingredient is easily fast when contacting with the surface of a wound
Speed is dissociated from dressing, cannot achieve the purpose of long-acting bacteriostatic.Chinese patent " polycaprolactone/natural polymer composite porous branch
The preparation method and application of frame " (patent No. CN102277737A) discloses a kind of utilization electrostatic spinning and Freeze Drying Technique
It prepares containing the natural polymer/polycaprolactone electrospun fiber membrane compound support frame material for having amino in the structures such as polylysine
Method.This method is laid particular emphasis on after introducing carboxyl in polycaprolactone strand and activate, the natural polymers such as grafting polylysine
To improve the surface wettability of polycaprolactone fiber, without reference to the polycaprolactone electrospun fiber membrane timbering material in patent content
Antagonistic property.In addition, the natural polymer spongy layer in polycaprolactone fiber surface have passed through crosslinking Treatment again after freeze drying,
It cannot water-soluble performance adhesiveness at once after being contacted with the surface of a wound.
Therefore, clinically there is an urgent need to one kind can effectively prevent Postoperative Intracranial Infections, preparation and clinical use process at present
Simply, it can suture and can directly adhere to the wide artificial hard brain (ridge) membrane patching material of use, industrialization prospect.
Summary of the invention
The object of the present invention is to provide a kind of endocranium that the antibiotic property with good anti-infective function is cation-modified to repair
Multiple material.
The cation-modified endocranium repair materials of antibiotic property provided by the present invention are in double-layer structure, and one layer is through ε-
The modified degradable polyester nano fibrous membrane of polylysine, another layer is the high molecular material of three-dimensional porous structure.
The degradable polyester nano fibrous membrane modified through epsilon-polylysine passes through electrostatic spinning process for degradable poly
Ester macromolecule is made nano fibrous membrane, rear surface-modified so that epsilon-polylysine is present in nanofiber surface is made.
The nano fibrous membrane with a thickness of 0.05-2 millimeters, fibre diameter is between 100-1000 nanometers, hole between fiber
Diameter size is between 300-3000 nanometers.
The degradable polyester macromolecule is selected from polylactic acid, polycaprolactone, polyglycolic acid, polydioxanone, poly- three
In carbonate, polyethylene glycol, poly butyric ester, poly- hydroxyl valerate, poly butylene succinate and polyurethane
One or more of copolymers, weight average molecular weight is between 30-500KDa.
Preferably, the degradable polyester macromolecule is l-lactic acid-caprolactone copolymer, and weight average molecular weight is
300KDa。
The high molecular material of the three-dimensional porous structure is made of the freeze-dried technique of natural polymer, has spongy
Porous structure, aperture size is between 10-1000 microns, with a thickness of 0.1-5 millimeters.
The natural polymer is selected from carboxymethyl chitosan, hydroxyl butyl chitosan, chitosan hydrochloride, chitosan quaternary ammonium
It is salt, Sodium Hyaluronate, carboxymethyl cellulose, hydroxyl acetopropion cellulose, oxidized regenerated cellulose, sodium alginate, collagen, bright
At least one of glue, chondroitin sulfate and fibrin, weight average molecular weight are 10-100 ten thousand.
Preferably, the natural polymer is Sodium Hyaluronate, and weight average molecular weight is 500,000.
The present invention also provides the preparation methods of the cation-modified endocranium repair materials of above-mentioned antibiotic property.
The method includes the following steps:
1) degradable polyester polymer electrostatic spinning solution is prepared, and degradable polyester fibre is obtained by electrostatic spinning process
Tie up membrane material；
2) the micro/nano fibrous membrane material surface obtained in step 1) introduces carboxyl；
3) the carboxylated micro/nano fibrous membrane material surface grafting epsilon-polylysine obtained in step 2), obtains epsilon-polylysine
Modified nano fibrous membrane；
4) natural polymer solution curtain coating is coated in the nano fibrous membrane table that the epsilon-polylysine that step 3) obtains is modified
Face, obtains the nano fibrous membrane that surface is coated with natural polymer solution, and freeze-drying is obtained containing three-dimensional porous macromolecule layer
Double-layer structure composite membrane, that is, the cation-modified endocranium repair materials of antibiotic property.
In above method step 1), the degradable polyester polymer electrostatic spinning solution is by by degradable polyester high score
Son is dissolved in specific solvent and is prepared.
The degradable polyester macromolecule is selected from polylactic acid, polycaprolactone, polyglycolic acid, polydioxanone, poly- three
In carbonate, polyethylene glycol, poly butyric ester, poly- hydroxyl valerate, poly butylene succinate and polyurethane
One or more of copolymers, weight average molecular weight is between 30-500KDa.
The solvent selection is acetone, dimethylformamide, dimethyl acetamide, tetrahydrofuran, methylene chloride, three chloromethanes
One or more of alkane, deionized water, 1,4- dioxane, hexafluoroisopropanol, ethyl alcohol, dimethyl sulfoxide, trifluoroacetic acid
Mixture.
The high molecular weight of degradable polyester accounts for solution gross weight in the degradable polyester polymer electrostatic spinning solution
1-20%.
Preferably, the degradable polyester macromolecule be polylactic acid-caprolactone copolymer, weight average molecular weight 300KDa,
High molecular weight accounts for the 10% of solution gross weight in spinning solution.Preferably, hexafluoro may be selected in the solvent of the electrostatic spinning solution
Isopropanol.
In above method step 1), used electrostatic spinning process are as follows: be first packed into prepared electrostatic spinning solution
Electrostatic spinning liquid supplying device；It is 0.1-20 mls/hour by the supply flow rate that flow pump regulates and controls Electrospun liquid, concretely
1 ml/hour；Adjusting high pressure end occurs with the distance between collection device is 3 centimetres -30 centimetres, concretely 15 centimetres；It is logical
It crosses high pressure generator and provides high pressure to electrostatic spinning process, can regulate and control between 0.1-40 kilovolts (concretely 15 kilovolts)；It will
The roller that revolving speed is 100-1000 revs/min (concretely 100 revs/min), diameter is 2-20 centimetres (concretely 8 centimetres) with connect
Ground terminal is connected, the collection substrate as electrostatic spinning process；It collects on a rotating drum and obtains degradable polyester high molecular nanometer
Tunica fibrosa, thickness is at 0.05-2 millimeters, concretely 0.2 millimeter, 0.25 millimeter.
In above-mentioned spinning technique, preferably, supply flow rate is set as 3 mls/hour, high pressure occur end with collection device it
Between distance be set as 10 centimetres, high pressure is set as 15 kilovolts, and the revolving speed of roller is set as 100 revs/min, and diameter of cylinder is 8 lis
Rice, degradable polyester macromolecular fibre film thickness are 0.2 millimeter.
In above method step 2), the method for introducing carboxyl on degradable polyester high polymer nanometer fiber membrane surface can
Select one of Low Temperature Plasma Treating, alkali process or ultraviolet irradiation processing.
The Low Temperature Plasma Treating method are as follows: by the polyester nano tunica fibrosa that step 1) obtains be placed on low temperature etc. from
In daughter reaction chamber, 0-10Pa (concretely 5Pa) is evacuated to after closing reaction chamber.It is passed through nitrogen, helium or oxygen later
Deng at least one reaction gas (concretely helium), adjusting work pressure is 5-50Pa (concretely 20Pa).It is steady to air-flow
Radio-frequency power supply is opened after fixed, regulation power is 10-100W (concretely 40W), and the processing time to tunica fibrosa is 0.1-10 points
Clock (concretely 1 minute), later takes out sample, obtains the degradable polyester high polymer nanometer fiber that surface introduces carboxyl
Film.
The alkali treatment method are as follows: under 0-10 DEG C (concretely 4 DEG C), polyester nano tunica fibrosa that step 1) is obtained
Be immersed in concentration be 0.05-1M (concretely 0.1M) aqueous slkali in, soaking time be 1-30 minutes (concretely 10 points
Clock), tunica fibrosa is taken out cleaned with a large amount of deionized waters later, obtains the degradable polyester high molecular nanometer that surface introduces carboxyl
Tunica fibrosa.
Alkali selected by the aqueous slkali can be at least one of sodium hydroxide, potassium hydroxide etc..
The ultraviolet irradiation processing method are as follows: it is 3- that the polyester nano tunica fibrosa that step 1) obtains, which is immersed in volume fraction,
In the hydrogenperoxide steam generator of 30% (concretely 10%), it is placed on that wavelength is 300-400nm, power is that 30-60W (specifically may be used
Under ultraviolet lamp for 40W), distance 5-20cm (concretely 10cm) is reacted 20-90 minutes (concretely 30 minutes) and is taken out afterwards
It is cleaned with a large amount of deionized waters, obtains the degradable polyester high polymer nanometer fiber membrane that surface introduces carboxyl.
In above method step 3), the method for carrying out epsilon-polylysine grafting in polyester nano fiber film surface are as follows:
Under 0-10 DEG C (concretely 4 DEG C), the carboxylated polyester nano fibrous membrane that step 2) obtains is immersed in containing 5-50mM (tool
Body can be 30mM) the N- hydroxyl amber of 1- ethyl -3- (dimethylamine propyl) carbodiimide (EDC) and 5-50mM (concretely 10mM)
In amber acid imide (NHS) mixed solution, soaking time is 4-24 hours (concretely 18 hours), takes out a large amount of deionized waters
After cleaning, it is poly- bad that the ε-that mass fraction is 0.5%-10% (concretely 1%) is immersed under 0-10 DEG C (concretely 4 DEG C)
In propylhomoserin solution, soaking time is 4-24 hours (concretely 10 hours), takes out and is cleaned later with a large amount of deionized waters, is obtained
The nano fibrous membrane modified to epsilon-polylysine.
In above method step 4), the additional amount of the natural polymer solution and the ratio of nano fibrous membrane surface area can
For 0.1-5ml/cm2(concretely 2ml/cm2)。
The lyophilized technique is that surface is integrally placed to freezing coated with the nano fibrous membrane of natural polymer solution to do
12-48 hours (concretely 20 hours) are lyophilized in dry machine, freeze temperature is -45~-5 DEG C (concretely -15 DEG C).
Above-mentioned natural polymer is selected from carboxymethyl chitosan, hydroxyl butyl chitosan, chitosan hydrochloride, chitosan quaternary ammonium
It is salt, Sodium Hyaluronate, carboxymethyl cellulose, hydroxyl acetopropion cellulose, oxidized regenerated cellulose, sodium alginate, collagen, bright
At least one of glue, chondroitin sulfate and fibrin, weight average molecular weight are 10-100 ten thousand.
Solvent in the natural polymer solution is deionized water, and natural polymer weight accounts for the 0.1- of solution gross weight
10%.
Preferably, the natural polymer is Sodium Hyaluronate, weight average molecular weight is 500,000, and it is total that high molecular weight accounts for solution
The 2% of weight.
The above method may also include the operation that the double-layer structure composite membrane for obtaining step 4) carries out sub-cut, sterilizing.
The cation-modified endocranium repair materials of above-mentioned antibiotic property are in preparation hard brain (ridge) membrane defect repairing product
Using also belonging to protection scope of the present invention.
The cation-modified endocranium repair materials of antibiotic property of the present invention have the advantages that
1, in composition containing with excellent anti-infection property can epsilon-polylysine, and it is present in a manner of surface grafting and receives
Rice fiber surface, permanently effective can prevent Postoperative Intracranial Infections.
2, the degradable polyester high polymer nanometer fiber contained in composition can provide good mechanical strength, so that this is artificial
Endocranium can bear certain suture power, not tear, not off-clip, can deformation occurs but it is damaged to be unlikely to；It is nanometer level microporous simultaneously
Structure can also effectively prevent the generation of tissue adhesion.
3, the three-dimensional porous natural polymer contained in composition may make the endocranium repair materials to have good aquation special
Property and compliance, while the good water soluble characteristic of natural polymer itself makes product that can directly attach use in clinical use,
Realization is exempted from suture and is fixed.
4, slowly degrade as time went on after implanting, finally can it is degradable and absorb, avoid diaphragm
Carcinogenic risk.
5, product form and preparation process are simple, and product quality is easily controllable, are able to achieve the industrialization of high-efficiency and low-cost
Production.
The cation-modified endocranium repair materials of antibiotic property of the present invention are a kind of structure novel, superior performance
New medical biomaterial repairs field in dura defect and shows good application prospect.
Detailed description of the invention
Fig. 1 is the structural schematic diagram of the cation-modified endocranium repair materials of antibiotic property, wherein 1 indicates three-dimensional porous day
Right macromolecule layer, 2 indicate the degradable polyester layers of nanofibers modified through epsilon-polylysine surface.
Specific embodiment
The present invention will be described below by way of specific embodiments, but the present invention is not limited thereto.
Experimental method used in following embodiments is conventional method unless otherwise specified；Institute in following embodiments
Reagent, material etc., are commercially available unless otherwise specified.
Embodiment 1
Polylactic acid-caprolactone copolymer (PLCL) that weight average molecular weight is 300,000 is dissolved in hexafluoroisopropanol, concentration
For 0.08 grams per milliliter, the solution of stable homogeneous is formed after being stirred at room temperature.Solution is placed in syringe later, syringe
High voltage power supply is connected at syringe needle.Solution supply flow rate is controlled at 1 ml/hour, and applying voltage is 15 kilovolts, and high-voltage end is the same as ground connection
The distance at end is 15 centimetres, uses the rotating cylinder that diameter is 8 centimetres as collection device, revolving speed is 100 revs/min.By PLCL
Nano fibrous membrane of the thickness at 0.2 millimeter or so is collected after solution-polymerized SBR.
PLCL nano fibrous membrane is placed in reaction of low temperature plasma room, is evacuated to 5Pa after closing reaction chamber, it
After be passed through helium, adjusting work pressure 20Pa.Radio-frequency power supply, regulation power 40W, to tunica fibrosa are opened after steady air current
Processing 1 minute after sample is taken out.
At 4 DEG C, it is molten that the PLCL nano fibrous membrane of carboxylated is immersed in the mixing containing 30mM EDC and 15mM NHS
In liquid, takes out after impregnating 18 hours and cleaned with a large amount of deionized waters.PLCL tunica fibrosa is immersed in mass fraction at 4 DEG C later
To take out after immersion 10 hours and being cleaned with a large amount of deionized waters in 1% epsilon-polylysine solution.
Sodium Hyaluronate (weight average molecular weight is 500,000) solution that mass fraction is 2% is prepared, according to 1.0ml/cm2It will be molten
Liquid is cast on the modified PLCL nano fibrous membrane of epsilon-polylysine, it is integrally placed to freeze-drying 12 in freeze drier later
Hour, freeze temperature is -15 DEG C, and cutting and sterilizing after taking-up can be obtained the cation-modified absorbable endocranium of antibiotic property and repair
Multiple material.
Embodiment 2
The l-lactic acid (PLLA) that weight average molecular weight is 300,000 is dissolved in chloroform, concentration is 0.1 gram/milli
It rises, forms the solution of stable homogeneous after being stirred at room temperature.Solution is placed in syringe later, is connected at syringe needle high
Voltage source.Solution supply flow rate is controlled at 1.5 mls/hour, and applying voltage is 17.5 kilovolts, distance of the high-voltage end with ground terminal
It is 12.5 centimetres, uses the rotating cylinder that diameter is 8 centimetres as collection device, revolving speed is 100 revs/min.PLLA solution is spun
Nano fibrous membrane of the thickness at 0.25 millimeter or so is collected after silk.
At 4 DEG C, PLLA nano fibrous membrane is immersed in the sodium hydroxide solution that concentration is 0.1M, soaking time 15
Minute, tunica fibrosa is taken out cleaned with a large amount of deionized waters later.At 4 DEG C, the PLLA nano fibrous membrane of carboxylated is impregnated
In the mixed solution containing 20mM EDC and 10mM NHS, takes out after impregnating 12 hours and cleaned with a large amount of deionized waters.Later
PLLA tunica fibrosa is immersed in the epsilon-polylysine solution that mass fraction is 0.5% at 4 DEG C, is taken out simultaneously after impregnating 5 hours
It is cleaned with a large amount of deionized waters.
Carboxymethyl chitosan (weight average molecular weight is 600,000) solution that mass fraction is 1.5% is prepared, according to 1.5ml/cm2
By in solution curtain coating to the modified PLLA nano fibrous membrane of epsilon-polylysine, it is integrally placed to freeze in freeze drier later
14 hours dry, freeze temperature is -10 DEG C, and cutting and sterilizing after taking-up can be obtained the cation-modified absorbable hard brain of antibiotic property
Film repair materials.
Embodiment 3
The polylactic-co-glycolic acid (PLGA) that weight average molecular weight is 250,000 is dissolved in acetone, concentration 0.2
Grams per milliliter forms the solution of stable homogeneous after being stirred at room temperature.Solution is placed in syringe later, at syringe needle
Connect high voltage power supply.Solution supply flow rate is controlled at 2 mls/hour, and applying voltage is 20 kilovolts, high-voltage end with ground terminal away from
From being 20 centimetres, use the rotating cylinder that diameter is 8 centimetres as collection device, revolving speed is 100 revs/min.PLGA solution is spun
Nano fibrous membrane of the thickness at 0.15 millimeter or so is collected after silk.
PLGA nano fibrous membrane is immersed in the hydrogenperoxide steam generator that volume fraction is 10%, being placed on wavelength is
Under 350nm, the ultraviolet lamp that power is 40W, distance 10cm, reaction is taken out after 30 minutes and is cleaned with a large amount of deionized waters.At 4 DEG C
Under, the PLGA nano fibrous membrane of carboxylated is immersed in the mixed solution containing 40mM EDC and 20mM NHS, it is small to impregnate 10
When after take out and cleaned with a large amount of deionized waters.It is poly- that PLGA tunica fibrosa is immersed in the ε-that mass fraction is 1.5% at 4 DEG C later
In lysine solution, takes out after impregnating 3 hours and cleaned with a large amount of deionized waters.
Carboxymethyl cellulose (weight average molecular weight is 700,000) solution that mass fraction is 2.5% is prepared, according to 0.5ml/cm2
By in solution curtain coating to the modified PLGA nano fibrous membrane of epsilon-polylysine, it is integrally placed to freeze in freeze drier later
10 hours dry, freeze temperature is -5 DEG C, and cutting and sterilizing after taking-up can be obtained the cation-modified absorbable hard brain of antibiotic property
Film repair materials.
Embodiment 4
It weighs after the artificial dura mater sample 0.75g in embodiment 2 is shredded and is put into the conical flask of a 50mL, addition contains
Have 103The nutrient broth 10mL of CFU/mL Escherichia coli bacteria suspension, is completely submerged in film in bacterium solution.Conical flask is fixed on vibration
It swings on shaking table, with 180r/min, 37 DEG C were co-cultured to 48 hours.Take respectively 4h, 8h, 20h, for 24 hours, 32h, 44h, 48h co-culture
Sample liquid 0.6mL afterwards, measures its OD value at 570nm.Control group and blank group are set simultaneously, and control group is poly- without containing ε-
The polyester nano tunica fibrosa of lysine, blank group are that the blank bacterium solution of sample is not added.Test is repeated 3 times altogether.The result shows that when altogether
Incubation time is more than after 12 hours, and cation-modified artificial dura mater group bacteriostasis rate is up to 99% or more, i.e. people in embodiment 2
Work endocranium product has significant antibacterial action.
Embodiment 5
Using new zealand rabbit 20 of healthy adult, at 19 monthly ages, for weight between 2.5 and 3.4 kilograms, male and female are unlimited.
Auricular vein injects 3% yellow Jackets (30 mg/kg) anesthesia.Along head median incision longitudinal incision scalp, successively divide
From to cranial periosteum, miniature abrasive drilling prepares about 1.2 centimetres of diameter of symmetrical round bone window in bilateral calvarium portion, in surgical operation microscope
8 × 8mm of lower preparation2Size dura defect.
The absorbable endocranium repair materials that embodiment 2 is prepared are cut into 12 × 12mm2It is hard to be attached to right side for size
Defect of meninges area, left side is without any processing to be used as blank control.After endocranium repair materials are implanted into, skin of head is stitched
It closes.Animal is put to death after implantation 6 months, dural patch and surrounding tissue is taken out, observes its exterior appearance, detected whether
Inflammatory reaction, and dural reconstruciton situation is observed, and whether stick together with surrounding tissue.Postoperative experimental animal single cage raising,
It maintains environment temperature and periodically feeds feed.
Postoperative all experimental rabbits are kept fit, and do not have the abnormal behaviours such as apparent epilepsy.Wound healing is good, hand
Art position is without tumour and bulging, no leakage of cerebrospinal.Obvious degradation, no inflammation reaction, with surrounding group occur for endocranium repair materials
No adhesion is knitted, implant site has one layer of newborn class endocranium connective tissue to generate.
The basic principles, main features and advantages of the present invention have been shown and described above.The technology of the industry
Personnel are it should be appreciated that the present invention is not limited to the above embodiments, and the above embodiments and description only describe this
The principle of invention, various changes and improvements may be made to the invention without departing from the spirit and scope of the present invention, these changes
Change and improvement all fall within the protetion scope of the claimed invention.The claimed scope of the invention by appended claims and its
Equivalent defines.
Claims (11)
1. a kind of endocranium repair materials that antibiotic property is cation-modified are in double-layer structure, one layer is modified through epsilon-polylysine
Degradable polyester nano fibrous membrane, another layer is the high molecular material of three-dimensional porous structure；
The method for preparing the cation-modified endocranium repair materials of the antibiotic property, includes the following steps:
1) degradable polyester polymer electrostatic spinning solution is prepared, and degradable polyester Nanowire is obtained by electrostatic spinning process
Tie up membrane material；
2) the micro/nano fibrous membrane material surface obtained in step 1) introduces carboxyl；
3) it is modified to obtain epsilon-polylysine for the carboxylated micro/nano fibrous membrane material surface grafting epsilon-polylysine obtained in step 2)
Nano fibrous membrane；
4) natural polymer solution curtain coating is coated in the nanofiber film surface that the epsilon-polylysine that step 3) obtains is modified, obtained
The nano fibrous membrane of natural polymer solution is coated with to surface, freeze-drying obtains the bilayer containing three-dimensional porous macromolecule layer
Structure composite film, that is, the cation-modified endocranium repair materials of antibiotic property.
2. the cation-modified endocranium repair materials of antibiotic property according to claim 1, it is characterised in that: described through ε-
By electrostatic spinning process nanometer is made in degradable polyester macromolecule by the modified degradable polyester nano fibrous membrane of polylysine
Tunica fibrosa, it is rear surface-modified so that epsilon-polylysine be present in nanofiber surface be made；
The nano fibrous membrane with a thickness of 0.05-2 millimeters, fibre diameter is between 100-1000 nanometers, aperture ruler between fiber
It is very little between 300-3000 nanometers.
3. the cation-modified endocranium repair materials of antibiotic property according to claim 1 or 2, it is characterised in that: described
Degradable polyester macromolecule be selected from polylactic acid, polycaprolactone, polyglycolic acid, polydioxanone, polytrimethylene carbonate,
One or more of polyethylene glycol, poly butyric ester, poly- hydroxyl valerate, poly butylene succinate and polyurethane are total to
Polymers, weight average molecular weight is between 30-500KDa.
4. the cation-modified endocranium repair materials of antibiotic property according to claim 1 or 2, it is characterised in that: described
The high molecular material of three-dimensional porous structure is made of the freeze-dried technique of natural polymer, has spongy porous structure,
Aperture size is between 10-1000 microns, with a thickness of 0.1-5 millimeters.
5. the cation-modified endocranium repair materials of antibiotic property according to claim 1 or 2, it is characterised in that: described
Natural polymer be selected from carboxymethyl chitosan, hydroxyl butyl chitosan, chitosan hydrochloride, chitosan quaternary ammonium salt, Sodium Hyaluronate,
Carboxymethyl cellulose, hydroxyl acetopropion cellulose, oxidized regenerated cellulose, sodium alginate, collagen, gelatin, chondroitin sulfate and
At least one of fibrin, weight average molecular weight are 10-100 ten thousand.
6. the method for preparing the cation-modified endocranium repair materials of antibiotic property of any of claims 1-5, packet
Include following step:
1) degradable polyester polymer electrostatic spinning solution is prepared, and degradable polyester Nanowire is obtained by electrostatic spinning process
Tie up membrane material；
2) the micro/nano fibrous membrane material surface obtained in step 1) introduces carboxyl；
3) it is modified to obtain epsilon-polylysine for the carboxylated micro/nano fibrous membrane material surface grafting epsilon-polylysine obtained in step 2)
Nano fibrous membrane；
4) natural polymer solution curtain coating is coated in the nanofiber film surface that the epsilon-polylysine that step 3) obtains is modified, obtained
The nano fibrous membrane of natural polymer solution is coated with to surface, freeze-drying obtains the bilayer containing three-dimensional porous macromolecule layer
Structure composite film, that is, the cation-modified endocranium repair materials of antibiotic property.
7. according to the method described in claim 6, it is characterized by: in step 1), the degradable polyester macromolecule Static Spinning
Silk solution is by the way that degradable polyester macromolecule dissolution to be prepared in specific solvent；
The degradable polyester macromolecule is selected from polylactic acid, polycaprolactone, polyglycolic acid, polydioxanone, poly- three methylene
One of base carbonic ester, polyethylene glycol, poly butyric ester, poly- hydroxyl valerate, poly butylene succinate and polyurethane
Or several copolymers, weight average molecular weight is between 30-500KDa；
The solvent selection be acetone, dimethylformamide, dimethyl acetamide, tetrahydrofuran, methylene chloride, chloroform,
The mixing of one or more of deionized water, 1,4- dioxane, hexafluoroisopropanol, ethyl alcohol, dimethyl sulfoxide, trifluoroacetic acid
Object；
The high molecular weight of degradable polyester accounts for the 1- of solution gross weight in the degradable polyester polymer electrostatic spinning solution
20%；
Used electrostatic spinning process are as follows: prepared electrostatic spinning solution is first packed into electrostatic spinning liquid supplying device；It is logical
The supply flow rate of inflow-rate of water turbine pump regulation Electrospun liquid is 0.1-20 mls/hour；It adjusts high pressure and end occurs between collection device
Distance be 3 centimetres -30 centimetres；High pressure is provided to electrostatic spinning process by high pressure generator, it can be between 0.1-40 kilovolts
Regulation；The roller that revolving speed is 100-1000 revs/min, diameter is 2-20 centimetres is connected with ground terminal, as electrostatic spinning process
Collection substrate；It collects on a rotating drum and obtains degradable polyester high polymer nanometer fiber membrane.
8. described in degradable polyester high molecular nanometer according to the method described in claim 6, it is characterized by: in step 2)
Fiber film surface introduces one of method choice Low Temperature Plasma Treating, alkali process or ultraviolet irradiation processing of carboxyl；
The Low Temperature Plasma Treating method are as follows: the polyester nano tunica fibrosa that step 1) obtains is placed on low temperature plasma
In reaction chamber, 0-10Pa is evacuated to after closing reaction chamber；It is passed through at least one reaction gas such as nitrogen, helium or oxygen later
Body, adjusting work pressure 5-50Pa；Radio-frequency power supply, regulation power 10-100W, to tunica fibrosa are opened after steady air current
Handling the time is 0.1-10 minutes, later takes out sample, obtains the degradable polyester high molecular nanometer fibre that surface introduces carboxyl
Tie up film；
The alkali treatment method are as follows: at 0-10 DEG C, it is 0.05- that the polyester nano tunica fibrosa that step 1) obtains, which is immersed in concentration,
In the aqueous slkali of 1M, soaking time is 1-30 minutes, takes out tunica fibrosa cleaned with a large amount of deionized waters later, obtain to surface and draw
Enter the degradable polyester high polymer nanometer fiber membrane of carboxyl；
Wherein alkali selected by the aqueous slkali can be at least one of sodium hydroxide, potassium hydroxide etc.；
The ultraviolet irradiation processing method are as follows: it is 3-30% that the polyester nano tunica fibrosa that step 1) obtains, which is immersed in volume fraction,
Hydrogenperoxide steam generator in, be placed under the ultraviolet lamp that wavelength is 300-400nm, power is 30-60W, distance 5-20cm, react
It takes out after 20-90 minutes and is cleaned with a large amount of deionized waters, obtain the degradable polyester high polymer nanometer fiber that surface introduces carboxyl
Film.
9. according to the method described in claim 6, it is characterized by: in step 3), it is described polyester nano fiber film surface into
The method of row epsilon-polylysine grafting are as follows: at 0-10 DEG C, the carboxylated polyester nano fibrous membrane that step 2) obtains is immersed in
In n-hydroxysuccinimide mixed solution containing 5-50mM1- ethyl -3- (dimethylamine propyl) carbodiimide and 5-50mM,
Soaking time is 4-24 hours, and after taking-up is cleaned with a large amount of deionized waters, it is 0.5%- that mass fraction is immersed at 0-10 DEG C
In 10% epsilon-polylysine solution, soaking time is 4-24 hours, takes out and is cleaned later with a large amount of deionized waters, obtains ε-
The modified nano fibrous membrane of polylysine.
10. according to the method described in claim 6, it is characterized by: in step 4), the additional amount of the natural polymer solution
Ratio with nano fibrous membrane surface area is 0.1-5ml/cm2；
The lyophilized technique is that the nano fibrous membrane that surface is coated with natural polymer solution is integrally placed to freeze drier
Interior freeze-drying 12-48 hours, freeze temperature are -45~-5 DEG C；
The natural polymer be selected from carboxymethyl chitosan, hydroxyl butyl chitosan, chitosan hydrochloride, chitosan quaternary ammonium salt, thoroughly
Bright matter acid sodium, carboxymethyl cellulose, hydroxyl acetopropion cellulose, oxidized regenerated cellulose, sodium alginate, collagen, gelatin, sulfuric acid
At least one of chondroitin and fibrin, weight average molecular weight are 10-100 ten thousand；
Solvent in the natural polymer solution is deionized water, and natural polymer weight accounts for the 0.1-10% of solution gross weight.
11. the cation-modified endocranium repair materials of antibiotic property of any of claims 1-5 are preparing hard brain ridge
Application in film defect repairing product.
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| CN109364294B (en) * | 2018-11-27 | 2019-12-17 | 普丽妍（南京）医疗科技有限公司 | Absorbable artificial dura mater and preparation method thereof |
| CN109847094B (en) * | 2018-12-25 | 2021-06-08 | 温州医科大学附属口腔医院 | Preparation method and application of multifunctional GTR gradient barrier film |
| CN110314557A (en) * | 2019-07-19 | 2019-10-11 | 武汉纺织大学 | A kind of bio-pharmaceuticals nanofiber coating sterilization film and preparation method thereof |
| CN112107736A (en) * | 2020-09-23 | 2020-12-22 | 成都美益达医疗科技有限公司 | Absorbable endocranium and preparation method thereof |
| CN113209384B (en) * | 2021-05-08 | 2022-03-25 | 宁波市第一医院 | Pelvic floor patch for gynecology and preparation method thereof |
| CN114032691A (en) * | 2021-11-12 | 2022-02-11 | 西南大学 | Flat-plate silk antibacterial composite material and preparation method thereof |
| CN115178029A (en) * | 2022-06-20 | 2022-10-14 | 苏州大学 | Air filtering membrane and preparation method and application thereof |
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