A kind of preparation method of porous artificial nerve catheter of the inner wall with orientation structure
Technical field
The invention belongs to the biomaterial for medical purpose fields in human implantable, and in particular to one kind is used for repairing nerve damage
Tissue engineering nerve conduit and preparation method thereof.
Background technique
In China, peripheral nerve injury patient populations are in the trend increased year by year.Although peripheral nerve has oneself certain
My repair function, but it is difficult to realize complete self-regeneration (especially long range neurologic defect), it is therefore desirable to by means of various minds
It is repaired through bridge material.Although Autologous bracket is the goldstandard for repairing peripheral nerve defection, but is faced with donor
The problems such as limited source, size mismatches and can cause permanent injury to materials position.Currently, people are mainly by by having
The various tissue engineering nerves bridge joint that the natural or synthetic biomaterial of preferable biocompatibility and biological degradability is prepared
Object realizes neural restoration.But these artificial nerve grafts promote the speed of peripheral nerve regeneration to be still difficult to meet clinical need
It wants, is especially difficult to repair the neurologic defect of relatively long distance (> 3cm), therefore, exploitation can comparatively fast promote peripheral nerve regeneration and energy
It realizes the new type nerve graft of relatively long distance neurologic defect reparation, while disclosing material with the interaction between nerve regneration
Relationship and inherent molecular mechanism have the design and clinical application that instruct peripheral nerve graft of new generation very important
Scientific meaning.
Material surface pattern technology can construct the surface with regular figureization distribution, and can accurate control figure
The width and depth of shape, controllability and repeatability with higher provide good thinking for solving the above problems.It grinds
Study carefully discovery, the biomaterial surface micrographics constructed on two-dimensional surface is conducive to regulation and correlation of the in vitro study figure to cell
Mechanism.As artificial nerve graft that the carinate figure of ditch is distributed can effectively induce and regulate and control nerve cell orientation grow with
Acceleration of nerve regeneration, orientation and the cell-ECM communication of the width and effect of depth nerve cell of ditch ridge.And column and circle
Other figure distributions such as platform then can be with the differentiation of Effective Regulation nerve cell.Applicant has found that striated is graphical under study for action
Chitosan can preferably induce and regulate and control the migration and orientation of schwann cells, and will not influence the original physiology function of cell
Energy.Therefore, the studies above shows reparation of the pattern technology for regulation nerve regeneration and acceleration peripheral nerve defection
With most important theories and application value.
Artificial nerve graft (the bracket/lead with different topology structure is designed and constructed from three-D space structure
Pipe), make it have the ability for carrying out bioelectric detecting to nerve cell and nerve regeneration becomes peripheral nerve regeneration in recent years
The research hotspot and difficult point of implanted device.Such as use freeze-drying method of molding and electrostatic spinning technique by material be processed into tubular structure for
Nerve regneration provides space appropriate and guiding function, still, since common nerve trachea inner wall does not have any modification, in pipe
Also without the filler of rush neural restoration, the function of repairing peripheral nerve defection is very limited.Therefore, it is necessary to conduit
Internal structure carry out more reasonable design (such as orientation inner wall), with construct can preferably inducing nerve cell growth and
Promote the microenvironment of nerve regneration.In recent ten years, change nerve trachea interior wall construction (such as inner wall orientation using various physico-chemical methods
Property, multi-channel type) or adding tube inner stuffing (such as built-in fabric bracket, built-in gel or the various factors and cell), to increase
Strong conduit own biological functionality has become research hotspot to advantageously promote nerve regneration.Such as using the tool of method of molding preparation
There is the PCL/ collagen nerve trachea of multichannel that can be obviously promoted the adherency and activity of schwann cells, and there is preferable mechanical property
Energy.Then the collagenous fiber bundle of laminin modified is filled into PCL/ collagen catheter chamber, is successfully realized the longer of dog
Reparation apart from Sciatic.And the various fibre bundles for promoting nerve growth migration or filiform are also filled into and lead
To promote neural restoration in pipe.In addition, the method electrospinning first for also thering is researcher's joint to use micrographics technology and electrostatic spinning
The PHBV-PLGA fiber of orientation is provided, then again with the PHBV-PLGA of the surface pattern prepared by same material
Film wraps up orientation fiber, and tube wall side stitches are finally become inner wall with orientation and while having the filling of orientation fiber
Nerve trachea, the conduit in terms of fast implementing repairing of neural injury have potential using value.It can be seen that conduit and pipe
The rational design of inner stuffing can advantageously promote neural restoration.However, the conduit with particular space form (orientation)
There are still certain difficulties for the building of inner wall.Although method of molding is easy to prepare conduit, it is difficult to obtain inner wall leading with orientation
It is difficult to be primarily due to removing for pipe.Method of electrostatic spinning can prepare the spinning fibre film of orientation arrangement, then film is crimped
The conduit that inner wall has orientation can be formed, but conduit side needs to realize closure by the method for suture or bonding, from
And it will increase inflammation odds;In addition it can which directly spinning is spun onto columned reception device, but due to made
Standby conduit is closer combined with mold, and pipe inner wall is easily damaged when removing.Micrographics technology can be very convenient
Building surface have orientation two-dimentional biomaterial surface, then material can be curled into catheter-like, but conduit side
The method by suturing or being bonded is needed to realize closure, equally increases inflammation odds.
Summary of the invention
The angle optimized from design of material and conduit biological function, promotees to further increase artificial nerve catheter
The ability of nerve regneration, exploitation inner wall has orientation topological structure and energy rapid induction neural cell adhesion is not necessarily to what is grown
The artificial nerve graft (conduit/bracket) of suture or bonding has the repairing of neural injury of peripheral nerve injury patient non-
Often important theory and application value.For this problem, currently, applicant creatively molds micrographics technology and freeze-drying
Method combines, and provides a kind of artificial nerve catheter for being conducive to neural cell adhesion, growth, which has orientation item
Line structure, catheter wall is in loose and porous structure, it is not necessary that duct wall is sutured or is bonded when use.In order to prepare the nerve
Conduit, the present invention also provides a kind of preparation methods that is simple and easy, being suitble to large-scale production.
Technical scheme is as follows:
A kind of inner wall has the porous artificial nerve catheter of orientation structure, it is characterised in that: the pipe inner wall surface
With orientation striated structure, the striated structure is made of zastrugi, and the surface of ditch is concave surface, and the surface of ridge is convex surface, ditch
5-50 microns of width, the width of ridge is 5-50 micron, and the vertical range between the surface of ditch and the surface of ridge is 1-10 microns.
The catheter wall of the conduit is in loose and porous structure.
The material for preparing of the conduit contains at least one of natural biologic material or synthesising biological material, wherein described
Natural biologic material includes at least one of chitosan, collagen, and the synthesising biological material includes in PCL, PLGA, PLA
It is at least one.
The conduit can also contain biomolecule or growth factor, and the biomolecule or growth factor include that layer connects egg
White, fibronectin, hyaluronic acid, polypeptide sequence, NGF, BDNF, at least one of GDNF.
The internal diameter of the conduit is 1-5 millimeters, and conduit wall thickness is 1-2 millimeters.
The catheter length is 10-80 millimeters.
The duct wall is not necessarily to manual suture or bonding.
The present invention also provides the preparation methods of above-mentioned artificial nerve catheter, this method comprises:
The micro- pattern of ditch ridge that micron-scale is constructed on metal foil, is then rolled into cylinder for paillon, cylinder is interior at this time
Wall has the micro- pattern of groove, then pours dimethyl silicone polymer (PDMS) in cylinder, and gold is removed after PDMS curing molding
Belong to paillon, the PDMS cylindrical body that outer wall has the micro- pattern of groove is obtained after cutting, a concentric circles is then added outside PDMS cylindrical body
Shape outer sleeve closes wherein one end, and the solution dissolved with conduit material, freeze-drying are added between PDMS cylindrical body and outer sleeve
Round jacket cylinder and PDMS cylindrical body are removed afterwards, obtain the artificial conduit that inner wall has orientation structure.
The metal foil can be titanium foil, aluminium foil, goldleaf, preferably titanium foil.
The micro- pattern of ditch ridge, 5-50 microns of the width of ditch, the width of ridge are 5-50 microns of ditches, and the surface of ditch is recessed
Face, the surface of ridge are convex surface, and the vertical range between the surface of ditch and the surface of ridge is 1-10 microns.
The barrel bore is 1-10 microns.
The PDMS solution is formulated by the dimethylsiloxane monomer that volume ratio is 10:1 and crosslinking agent.
The material for preparing of the conduit contains at least one of natural biologic material or synthesising biological material, can also contain
Biomolecule or growth factor, wherein the natural biologic material includes at least one of chitosan, collagen, the synthesis life
Object material includes at least one of PCL, PLGA, PLA, the biomolecule or growth factor include laminin, fine even egg
White, hyaluronic acid, polypeptide sequence, NGF, BDNF, at least one of GDNF.
The conduit of preparation method and preparation of the invention has the advantage that
1, the artificial nerve catheter is without being sutured or being bonded to catheter wall;
2, inner wall has the complete candy strip of rule, is conducive to neural cell adhesion, growth;
3, catheter wall is loose and porous structure, conducive to the exchange of the metabolic object of the transport and cell of nutriment, separately
The various growth factors for also promoting nerve regneration outside for load provide good platform;
4, conduit is easily peeled off, and preparation method is simple, is suitble to large-scale production.
Specific embodiment
Present invention will be further explained below with reference to specific examples.It should be understood that these embodiments are merely to illustrate the present invention
Rather than it limits the scope of the invention.In addition, it should also be understood that, after reading the content taught by the present invention, those skilled in the art
Member can make various changes or modifications the present invention, and such equivalent forms equally fall within the application the appended claims and limited
Range.
Embodiment 1
(1) preparation of the design of micrographics size and pure titanium foil piece motherboard
Dimension of picture: ditch/ridge width is the um of 5 um/5,10 um/10 um, 20 um/20 um, 30 um/30
Um, 50 um/50um, graphics depth be 1 um, 2 um, 4 um, 6 um, 10 μm.Using laser microscopic carvings lithography in pure titanium
The carinate micro- pattern of ditch of above-mentioned dimension of picture is carved out on paillon, engraving area is 10cm × 10cm.
(2) outer wall has the preparation and characterization of the PDMS cylindrical body elastomeric stamp of orientation figure
Along striped be orientated by pure titanium foil piece be curled into inner wall with micrographics different inner diameters (1mm, 3mm, 5mm, 7mm,
Cylinder 10mm), will prepared PDMS(monomer at room temperature: crosslinking agent=10:1(volume ratio)) it is cast to there is certain micro- figure
In the pure titanium foil piece catheter mold of shape size (micrographics is in pure titanium foil piece pipe inner wall), then put it into vacuum oven
Exclusion bubble is vacuumized, and carries out dry solidification, removing obtains outer wall with the carinate micrographics of ditch point after finally being solidified
The PDMS cylindrical body elastomeric stamp of the different-diameter of cloth.Using scanning electron microscope to the ditch ridge graphic scale of PDMS cylindrical body elastomeric stamp
Very little and depth is detected.
(3) side wall is without suture and inner wall has the preparation of the porous nerve trachea of orientation micrographics
Side wall is prepared without suture using micrographics technology and freeze-drying method of molding and inner wall has the more of orientation micrographics
Hole nerve trachea.Certain density chitosan/collagen mixed solution is prepared first, and then the solution is filled into outer wall ditch
In the catheter mold of the carinate PDMS cylindrical body elastomeric stamp composition being graphically distributed, bubble removing is vacuumized, after freeze-drying,
Conduit can be completely stripped and obtain the porous artificial nerve catheter that side wall has orientation micrographics without suture and inner wall, and
It is bad that tube wall is intact.
(4) inner wall for loading bioactive molecule has porous chitosan/collagen nerve trachea of orientation micrographics
Preparation
At room temperature, certain density (5 μ g/mL, 10 μ g/mL, 50 μ g/mL) are had to the biology for promoting nerve regneration function
Molecule (laminin, fibronectin, hyaluronic acid, polypeptide sequence (YIGSR, IKVAV) or the various factors for promoting nerve growth
Then (NGF, BDNF, GDNF etc.) uses micrographics technology first with the abundant blending reaction of chitosan/collagen mixed solution 2 hours
Solution after blending is prepared into the film of the carinate micrographics distribution of surface ditch with freeze-drying method of molding;Or the method using grafting
Certain density bioactive molecule is directly fixed to the porous membrane of surface pattern by (covalent bond or electrostatic interaction)
On, to realize fixation of the bioactive molecule in the orientation distribution of pipe inner wall and conduit porous structure respectively.