A kind of method for preparing of galvanic deposit calcium phosphorus mineralized layer superfine fibre bone material
Technical field
The invention belongs to the preparation field of electric-woven super-fine fiber bone material, particularly relate to a kind of method for preparing of galvanic deposit calcium phosphorus mineralized layer superfine fibre bone material.
Background technology
The bone that causes because of a variety of causes is damaged, and the treatment that bone is damaged especially on a large scale remains a great problem that clinical medicine faces.Traditional exist as supply that the bone amount is limited, osteogenic ability is low, be prone to cause immunoreation and shortcoming such as spread disease, can't satisfy the requirement of clinical treatment from body or allogenic bone transplantation.
The biomineralization system that the main component of nature bone is made up of collagen fiber and hydroxyapatite (HA) crystal.Structurally; Nature bone is the composite organic-inorganic material with complicated hierarchy that is formed through HA by collagen fiber; With diameter is the main body frameworks of the collagen fiber of 100~2000nm by certain oriented formation bone; The filling of ultra-fine level HA crystal therebetween, its crystallization direction distributes along the major axis of collagen fiber.The unique multilevel hierarchy of nature bone makes it have mechanical properties such as high strength, high tenacity.Therefore simulate the formation mechanism of nature bone, adopt bionic method prepared composition, the structure organic and inorganic compound bone material similar with nature bone is the focus of bone material research always.
Adopting calcium, phosphorus inorganic salt and the macromolecular material composite methods close with the nature bone composition is the main thought of current preparation bionic scaffold material.As adopt phase detachment technique and rapid shaping technique HA and high polymer material to be processed into the composite of HA and high polymer through certain preparation method.But this material through direct compound preparation is the mechanical mixture of two kinds of materials, is difficult to form inorganic matter and the tight bonding of Organic substance on molecular level, can only be from composition and can not carry out bionical from structure.Another kind is an in-situ compositing; In polymer matrix inside or surface the composite that chemical reaction directly prepares HA and high polymer taking place through calcium salt and phosphate, can overcome direct compound tense HA and in polymer matrix, disperse uneven and the unmanageable shortcoming of composite structure.A kind of method for preparing that is used for the nm-crysal collagen-based calcium phosphate composition of bone reparation is disclosed like Chinese patent (application number 01136246.4); But this Compound Material Engineering intensity that is formed by self assembly merely is on the low side; Be difficult to obtain clinical practice widely, need to add new biology performance and the mechanical strength of component to improve material.In self assembly nHA/ collagen-based materials, add alginate and PLGA like Chinese patent (patent No. 01141901.6,01129699.2) respectively; Process the porous framework material; When keeping the good biocompatibility of self-assembled material; Improve the mechanical strength of material, had good clinical application prospect.
The static spinning superfine fibre can be simulated the ultrastructure of n cell epimatrix, is considered to a kind of ideal tissue substitute material.In recent years, many both at home and abroad researchs attempt adopting diverse ways to prepare organic and inorganic composite ultrafine fiber bone material.A kind of method is that bone ore deposit compositions such as HA are joined in the polymer solution, and directly electricity spins the HA composite ultrafine fiber.Though this method can be compound to bioactive molecules such as somatomedin in the material; But hydrophilic inorganic constituents and hydrophobic polymer phase capacitive are relatively poor; Need select special solvent for use or by surfactant; Inorganic constituents possibly reunited or disperse uneven in composite fibre, and the content of inorganic constituents is also owing to receiving the spinnability restriction to be difficult to improve (Kim HW, et al.J BiomedMater Res A 2006; 79 (3): 643-649.), the mechanical strength of material also can't reach requirements for clinical application (Sui G, et al.J Biomed Mater Res A 2007; 82 (2): 445-454.); Another kind method is that first electricity spins the polymer superfine fibre film, is placed among the SBF and soaks a period of time, makes HA be deposited on the superfine fibre surface preparation and goes out composite cellulosic membrane (Chen J, et al.J Biomed Mater Res A 2006; 79 (2): 307-17.).This method can overcome the mixing electricity and spin the inorganic constituents problem of uneven distribution that causes, also can improve the content of mineralogical composition.But mineralization process needs the long time, causes the degraded of composite fibre easily, is not suitable for the load of bioactive ingredients.
Summary of the invention
Technical problem to be solved by this invention provides a kind of method for preparing of galvanic deposit calcium phosphorus mineralized layer superfine fibre bone material; The porous bone material that the present invention is prepared; Be similar to the bone ore deposit composition that the nature bone forming process produces to a certain extent, have better biocompatibility.
The method for preparing of a kind of galvanic deposit calcium phosphorus mineralized layer superfine fibre bone material of the present invention comprises:
(1) electricity spins the preparation of solution: use solvent and electric woven material compound concentration to spin solution as the electricity of 6%-15%;
(2) electrostatic spinning prepares superfine fibre: the electricity that will prepare spins solution packs in the electrostatic spinning apparatus, and the electricity spinning is equipped with polymer superfine fibre, and the control electricity spins parameter, makes the fiber surface of preparation uniform and smooth; Collect superfine fibre with stainless steel electrode or platinum electrode, the pole piece and the support section of electrode are detachable, and electrode slice uses through polishing with after cleaning, and guarantees that the mineralising superfine fibre is easy to separate from pole piece;
(3) preparation of electric depositing solution: with proper C a (NO
3)
2And NH
4H
2PO
4Two kinds of materials join mix homogeneously in the deionized water respectively, and with the pH value of ammonia and hydrochloric acid conditioning solution, obtaining concentration is the Ca (NO of 0.01~0.2mol/L
3)
2Solution, concentration are the NH of 0.01~0.05mol/L
4H
2PO
4Solution, the pH value of solution are 3.1~5.2;
(4) electrochemical deposition of electrospinning fibre: with the stainless steel electrode that covers superfine fibre film is that negative electrode, platinum electrode are anode, adding electric depositing solution; Water bath with thermostatic control control electrodeposition temperature is 30~70 ℃, constant voltage-1.5~-3.0V, constant current 0.1~10mA/cm
2Deposition; Electrode distance is 1.5~3cm, and sedimentation time is 15~120min, makes the calcium microcosmic salt pattern even compact, structurally ordered of generation; The mineralising superfine fibre of preparation takes off from electrode to be rinsed well; Through 0.1~1.0mol/LNaOH solution soaking, 1~24h, make synthos partly be converted into hydroxyapatite (HA), clean the back and in air, dry;
(5) machine-shaping of porous bone material:, be the NH of 1:0.5-1 again with mol ratio with range upon range of the adding up of mineralising superfine fibre 50-100 of preparation
4HCO
3And the even spreading of mixture of two kinds of salt of NaCl (particle diameter is controlled at 100~500 μ m) with being placed in the stainless steel mould, is cast into bulk at room temperature, 10~40MPa between each layer fiber, places 60~90 ℃ hot water to soak about 5~30min, NH material
4HCO
3Decomposes discharges ammonia and carbon dioxide is overflowed from material, on material, forms micron-sized aperture, places 50~70 ℃ of water-baths to soak 10~30min bulk material again, removes remaining NaCl particle, and last bone material is in-5~-20 ℃ of following lyophilizing;
(6) sterilization and packing: the bone material of above-mentioned preparation encapsulates with double-layer polyethylene film, and oxirane disinfection is preserved subsequent use after 2~4 hours.
The electric woven material of said step (1) comprises various natural, synthetic polymers and both complex.
Described natural polymer comprises native protein, polysaccharide and composites thereof such as collagen protein, elastin laminin, gelatin, fibroin albumen, Fibrinogen, vegetable protein, hyaluronic acid, chitosan, Bacterial cellulose; Synthetic polymer comprises and gathers Acetic acid, hydroxy-, bimol. cyclic ester, polylactide, polycaprolactone, poe, gathers anhydride, polyglycolic acid and various copolymer thereof.
Said step (1) solvent is selected from oxolane, dehydrated alcohol, acetic acid, hexafluoroisopropanol, acetone, trifluoroethanol, dichloromethane, chloroform, N, the mixed solvent of one or more in the dinethylformamide.
The electric spinning method of said step (2) comprises the single nozzle electrospinning of employing, coaxial cospinning and mixes electrospinning, preparation one pack system, skin-core, compound superfine fibre.
It is that voltage is 16.0-25KV that said step (2) electricity spins parameter; Receiving range is 15.0cm-20.0cm; Feed flow speed is 1.2ml/h-2ml/h, and PLLA (PLLA) fibrous membrane of the thick about 0.1mm of 30min rear electrode surface coverage changes the PLLA fibrous membrane that the electrode another side receives same thickness.
The porosity of said step (5) porous bone material is controlled at 50~90%, and pore diameter range is controlled to be 50~500 μ m;
The main component of described calcium phosphorus mineralized layer is brushite and hydroxyapatite.
The calcium phosphorus mineralized layer superfine fibre bone material of above-mentioned preparation adopts salt grain leaching/gas foaming technology to be processed into the porous bone holder material, to be used for bone defect repair clinically.
The electric-woven super-fine fiber that relates among the present invention is meant the nanometer, submicron or the micron order that adopt medically acceptable any material electricity spinning to be equipped with (diameter 0.1 nanometer to 10 micron) fiber, and the difference of spinning processing mode according to electricity can obtain one-component, skin-core, the different composition and the superfine fibre of fine structure such as compound.
The porous bone material that the present invention is prepared because of bone mineral has special preferred orientation property in electrochemical deposition process, is similar to the bone ore deposit composition that the nature bone forming process produces to a certain extent, has better biocompatibility.Electrochemical deposition technique is used for the biomineralization of electric-woven super-fine fiber; Can prepare the composite organic-inorganic material that contains higher mineralogical composition in the short period of time; Because preparation time is short and mild condition, can not cause that the bioactive ingredients that loads in the superfine fibre discharges and inactivation in advance.For reaching the purpose of treatment and healing acceleration, in electrospinning fibre, can add various bioactive ingredients, comprise various curative drugs, antibiotic, somatomedin, oligonucleotide, polynucleotide etc.
Beneficial effect
(1) the porous bone material of the present invention's preparation is similar to the bone ore deposit composition that the nature bone forming process produces to a certain extent, has the compatibility preferably;
(2) the present invention's porous bone material here has appropriate bore gap structure and mechanical property;
(3) the short and mild condition of preparation time of the present invention can not cause that the bioactive ingredients that loads in the superfine fibre discharges and inactivation in advance.
Description of drawings
Fig. 1 is the SEM pattern photo of the PLLA superfine fibre of preparation, and A is that static spins gained PLLA superfine fibre; B is-the 2.0V running voltage under behind the electro-deposition 60min, the cellular calcium microcosmic salt of formation is covered in the fibrous membrane surface;
Fig. 2 is the XRD diffraction spectrogram of sample among the embodiment 1, the commercialization HA particulate XRD diffracting spectrum of A for buying; B is that static spins gained PLLA superfine fibre soaks 60min in electrolyte XRD diffracting spectrum; The back XRD diffracting spectrum of the C electro-deposition 60min that is the PLLA superfine fibre under-2.0V running voltage.After 60 minutes, 2 θ=11.8 on the spectrogram.It is thus clear that obviously sharp peak is the characteristic peak of calcium hydrogen phosphate salt, at 25.8 °, 32 °, HA characteristic peak place is the indefinite form peak, has generated section H A after can knowing 60min in conjunction with the FTIR collection of illustrative plates.So its fiber mineralized layer is calcium hydrogen phosphate salt and HA salt-mixture; Fig. 3 is the FTIR spectrogram of sample among the embodiment 1, the commercialization HA particulate FTIR of A for buying; B is that static spins gained PLLA superfine fibre soaks 60min in electrolyte FTIR; The C FTIR behind the electro-deposition 60min that is PLLA superfine fibre template under-2.0V running voltage.At 1000~1100 (cm
-1) its peak is sharply obvious, is PO
4 3-, H
2PO
4-, HPO
4 2-Absorption region, in conjunction with 870 (cm
-1) locate the peak and XRD result can confirm phosphoric acid hydrogen calcium salt.At 3510cm
-1The hydroxyl characteristic absorption peak of the visible HA in place in conjunction with the XRD characterization result of figure two, shows and contains section H A in the calcium-phosphate layer.
The specific embodiment
Further set forth the present invention below in conjunction with specific embodiment.Should be understood that these embodiment only to be used to the present invention is described and be not used in the restriction scope of the present invention.Should be understood that in addition those skilled in the art can do various changes or modification to the present invention after the content of having read the present invention's instruction, these equivalent form of values fall within the application's appended claims institute restricted portion equally.
Embodiment 1
(1) be that the chloroform/acetone of 3:1 is a solvent with the volume ratio, preparation 6% (w/v) PLLA (molecular weight 130,000) electricity spins solution;
(2) choose the platinum electrode of 2cm * 2cm, the surface is through polishing and be used as electricity after cleaning and spin gathering-device, adopts single shower nozzle electrospinning to prepare the PLLA superfine fibre at electrode surface.Adopting 21G entry needle (internal diameter 0.51mm) is spinning head, and HV generator provides high direct voltage, and micro-injection pump carries electricity to spin solution; Electricity spins parameter: voltage is 16.0KV, and receiving range is 15.0cm, and feed flow speed is 1.2ml/h, and the PLLA fibrous membrane of the thick about 0.1mm of 30min rear electrode surface coverage changes the PLLA fibrous membrane that the electrode another side receives same thickness;
(3) preparation 100ml electrolyte, wherein Ca (NO
3)
2The concentration of solution is 0.042mol/L, NH
4H
2PO
4The concentration of solution is 0.025mol/L, and calcium-phosphorus ratio is 1.67 in the solution, and regulating pH value is 4.7.With two-sided collection the platinum electrode of PLLA nanofiber being arranged is negative electrode, and the another platinum electrode is an anode, uses the constant voltage mode to carry out electrochemical deposition; Sedimentary condition: voltage is-2.0V, and electrode distance is 2.5cm, and sedimentation time is 60min; The mineralising nanofiber sample of preparation soaks 2h through 0.1mol/L NaOH, cleans the back and in air, dries subsequent use naturally; The same terms is the mineralising fibrous membrane of 50 same sizes of preparation down;
The 50 lump ore superfine fibre multilamellars that (4) will prepare stack up containing NH
4HCO
3And the even spreading of mixture that two kinds of salt of NaCl (particle diameter 200~300 μ m) are formed is between each layer fiber, will prop up subsequently to be placed in the self-control stainless steel mould, about room temperature, 20MPa, is cast into bulk.Bulk material adopts salt grain leaching/gas foaming technology to process porous material.Promptly place 80~90 ℃ hot water to soak about 10min bulk material earlier, will prop up to be placed in 60 ℃ of water-baths again and soak 20~30min, remove remaining NaCl particle, last support is in-20 ℃ of following lyophilizing;
(5) material of preparation encapsulates with double-layer polyethylene film, and oxirane disinfection is preserved subsequent use after 2 hours.
The PLLA superfine fibre SEM pattern photo see Fig. 1.
Embodiment 2
(1) material therefor is for engraving the type i collagen (molecular weight 0.8~1.0 * 10 that lets Bioisystech Co., Ltd buy from Sichuan
5), the employing hexafluoroisopropanol is a solvent, compound concentration is that the electricity of 8% (w/v) spins solution;
(2) two-sided reception electricity spins collagen fiber on platinum electrode.Electricity spins parameter: voltage is 15KV, and receiving range is 10cm, and feed flow speed is 0.8ml/h, and the single-side electrode time of reception is 30min.Treat that the two-sided collagen fiber of all having collected of electrode are placed in the vacuum drying oven that evacuation 12h removes residual solvent under the room temperature;
All the other prepare mineralized collagen porous bone material with embodiment 1.
Embodiment 3
With embodiment 1, different is to adopt coaxial cospinning (coaxial electrospinning) technology two-sided preparation skin-core electric-woven super-fine fiber on platinum electrode.It is interior pin (internal diameter 0.51mm, external diameter 0.8mm) that coaxial cospinning device in the present embodiment adopts the 21G entry needle, and outer nozzle needle internal diameter is 1.6mm.The about 5mm of the inside indentation of interior nozzle needle mouth.Cortical material adopts 10% (w/v) PLLA electricity to spin solution, core matter adopts the 3%PEO that adds rhBMP-2 (rhBMP-2) (80~100 μ g/mL electricity spin liquid), is that solvent preparation skin, sandwich layer electricity spin solution with chloroform and physiological saline solution respectively.The control output voltage is 18KV during coaxial cospinning, and the liquid supply speed of skin, sandwich layer solution is respectively 3ml/h and 0.4ml/h, and receiving range is 12cm.
All the other same embodiment (1) prepare the porous bone material.
Embodiment 4
With embodiment 1, different is to adopt the mixing electricity to spin (mixing electrospinning) technology two-sided preparation collagen/PLLA composite ultrafine fiber on platinum electrode.In the mixing electricity spun, 8% (w/v) type i collagen and 10% (w/v) PLLA solution deposited on the platinum electrode from two spouts respectively simultaneously, have obtained the composite cellulosic membrane of two kinds of material interlacings.Electricity spins parameter: voltage is 16KV, and receiving range is 10cm, and feed flow speed is 1.5ml/h.
All the other same embodiment (1) prepare the porous bone material.