CN1569736A - Preparation method of degradable porous calcium-silicate ceramic bioactive materials - Google Patents
Preparation method of degradable porous calcium-silicate ceramic bioactive materials Download PDFInfo
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- CN1569736A CN1569736A CN 200410058919 CN200410058919A CN1569736A CN 1569736 A CN1569736 A CN 1569736A CN 200410058919 CN200410058919 CN 200410058919 CN 200410058919 A CN200410058919 A CN 200410058919A CN 1569736 A CN1569736 A CN 1569736A
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Abstract
The invention relates to the preparation method of degradable porous calcium-silicate ceramic bioactive materials by using calcium silicate micro powder made through moisture chemical method as raw material, adding organic or macromolecular pore-forming agents of different particle sizes, mixing and dry-pressing for formation, or gel injection molding to obtain the porous material blank, finally calcining the blank at an elevated temperature.
Description
Technical field
The present invention relates to a kind of preparation of degradeable bioactive porous active calcium silicate ceramic material, belong to technical field of biological material.
Background technology
Existing human body hard tissue reparation and replacement material have metallic substance, stupalith, macromolecular material and matrix material etc. several, and relative merits are respectively arranged.From bionical angle, if can obtain the composition material close then be best with body bone tissue.A kind of good biomaterial must possess excellent biological compatibility and biological activity are arranged, and has suitable mechanical property simultaneously.
Medical hard tissue repair of lithotroph and replacement material aspect mainly contain calcium-phosphorus base biomaterial and calcium-silica-based biomaterial.Wherein calcium-phosphorus base biomaterial research has had very long history, past discover that hydroxyapatite class biomaterial has biological activity preferably in calcium-phosphorus sill, but degradation property is poor, and tricalcium phosphate class biomaterial degradation property better but biological activity is low.Calcium-silica-based biomaterial such as bioactivity glass and Calucium Silicate powder class material were then owing to not only had superior bioactive but also have good degradation property and more and more come into one's own in recent years.
The eighties in 20th century Japan people such as Kokubo (J.Mater.Sci., 1986, the A-W glass that 21:536) works out be a kind of in glassy phase the glass-ceramic of precipitation of phosphorus lime stone and two kinds of crystalline phases of Calucium Silicate powder.This material has preferably mechanical mechanics property and biological activity but can not degrade.P.N.de Aza (the Biomaterials of Spain San Diego university, 1997,18:1285) prepare fine and close biological ceramics and studied the biological activity of this material with tricalcium phosphate and Calucium Silicate powder congruent melting, studies show that in simulated body fluid, osteolith can form on the surface of wollastonite ceramics, people's such as Kokubo research also confirms, CaO-SiO in simulated body fluid
2The base glass surface can form the osteolith layer, and CaO-P
2O
5The base glass surface does not have osteolith to form.People such as Punnama (J.Biomed.Mater.Res., 2000,52:30) find, faster in the formation speed of simulated body fluid mesosilicic acid calcium ceramic surface osteolith than other biological glass and glass-ceramic.Our research shows that also Calucium Silicate powder pottery biomaterial has good biological activity, favorable biological degradability and good mechanical performance.Except the composition of material, the structure of material can directly have influence on the clinical application of material to a great extent.Studies show that in the past, the aperture is suitable as hard tissue repairing material and cytoskeleton material most at the porous blocks biomaterial of 50-500 micron.The aperture the advantage of the porous biomaterial of this scope be help cell migration, tissue is grown into and thereby the fusion of material and biological tissue more effectively reaches the purpose of the damaged and tissue reconstruction of reparation tissue.Organize and to strengthen being stationed and stability of planting material in the vesicular structure of growing into.In addition, in the organizational engineering research that developed rapidly in recent years, biodegradable porous biomaterial is a requisite part., allow cell in substrate material, grow and make up the biological tissue that contains this somatic cell gene information as cell carrier with porous support, again in the implant into body with repair deficiency tissue and organ.Therefore, the degradable porous gastrosil bioceramic material is as sclerous tissues's impairment renovation material be used for external osseous tissue cultured cells support and have a wide range of applications.
Yet the preparation of degradable porous gastrosil bioceramic material yet there are no report.
Summary of the invention
The objective of the invention is to go out a kind of new have good mechanical property, biological activity and biodegradability by optimizing process exploitation, the porous biomaterial of while aperture and controlled porosity and tool through hole, as sclerous tissues's impairment renovation material and external osseous tissue cultivation cytoskeleton material, to satisfy the needs of biomaterial development of new generation.
The bioactivity glass that studies show that of Hench is the composition that can cause special physiological response.When bioactivity glass was exposed in the ambient body fluid, ion-exchange and irregular surface dissolution effect can produce a hydrated silica gel layer, thereby had increased specific surface area and promoted at coarse formation one deck crystallite osteolith layer on glass.This layer not only with the bone forming synostosis, also combine with collegen filament, fix thereby make such material form biology with tissue.
The porous calcium silicate pottery biomaterial that provides with preparation method of the present invention has good biological activity in human body simulation body fluid, similar to bioactivity glass, can discharge silicon ion in a few hours, and on surface deposition the crystallite osteolith.In addition, Calucium Silicate powder biological ceramics of the present invention also has good degradability, and the extracorporeal dissolution-ability experiment is presented at the following 5 days degradation rate of simulated body fluid environment about 31%.Therefore, porous calcium silicate bioceramic material of the present invention had both had good bioelectric interface and chemical property, had good biodegradability again.
Another characteristics of the present invention are to make material both have higher void content (40-80%) and suitable aperture (50-500 micron) by the CONTROL PROCESS condition, have suitable mechanical strength (ultimate compression strength is 3-80MPa) again.
In sum, porous calcium silicate bioceramic material of the present invention has unique advantage as sclerous tissues's impairment renovation material and the cultivation of external osseous tissue with the cytoskeleton material.
Embodiment of the present invention are as follows:
1, material preparation
Calcium silicate micro power of the present invention prepares by chemical process.Used inorganic raw material is analytically pure Ca (NO
3)
24H
2O, Na
2SiO
39H
2O, ammoniacal liquor, water are deionized water.Ca (the NO of preparation 0.1-1.0mol/L
3)
24H
2O and Na
2SiO
39H
2O solution, with etc. the material reaction of mol ratio, the speed of pressing 1-3ml/min is with Na
2SiO
3Solution adds Ca (NO
3)
2In the solution, material finishes the back and continue to stir 8-24 hour, filters and with deionized water and the residual Na of dehydrated alcohol thorough washing removal
+Ion, the powder that oven dry obtains was calcined the controlled β-CaSiO at 100nm-250 μ m of granularity behind the ball milling 1-3 hour in 800-1000 ℃ after ball milling sieves
4Micro mist.Preferred particulates degree of the present invention is 100nm-150 μ m.The preferred kind of pore-forming material of the present invention is organic or macromolecular materials such as PEG (polyoxyethylene glycol), PVA (polyvinyl alcohol), paraffin, polystyrene-divinylbenzene, and its granularity preferable range is the 100-700 micron.Adopt the pore-forming material of the 30-60% (mass percent) of certain granules degree scope to mix with calcium silicate micro power, can take two kinds of forming methods afterwards, first kind is dry pressing, the PVA (polyvinyl alcohol) that promptly adds 1-5% (mass percent) concentration and be 1-10% in above-mentioned compound makes cakingagent, after mixing, in punching block with the pressure of 2-20MPa dry-pressing formed porous material biscuit of the present invention; Second method is a gel-casting method, promptly is formulated as follows the aqueous solution of mass percent concentration earlier, the PMAA-NH of 20% AM, 2% MBAM and 5-10%
4By volume the ratio of per-cent 30-60% is even with above-mentioned aqueous solution with above-mentioned compound, the TEMED number droplet that adds ammonium persulphate number droplet, the mass percent 1-5% of mass percent 1-5%, stir the equal slurry preferably of mobile and homogeneity, pour slurry into plastics or gypsum mold inner gel casting, and, get porous material biscuit of the present invention 100 ℃ of dry a few hours afterwards crosslinking reaction 1-10 hour of 30-80 ℃ of trigger monomer.Biscuit with two kinds of technology gained obtained porous material of the present invention in 1-5 hour 900-1400 ℃ of calcining at last.
2, performance evaluation
2.1 the mechanical strength of porous material
The series of samples that the present invention obtains is tested ultimate compression strength on the accurate universal testing machine of AG-I of day island proper Tianjin company.The test speed of sample is 5.0mm/min, the caning be controlled in the 3-80MPa scope of the ultimate compression strength of the porous material that test shows the present invention obtains.
2.2 the porosity of porous material
The sample segment that we obtain the present invention is used Archimedes's method test porosity, application scanning Electronic Speculum (SEM) vision slit form and pore distribution.The controlled porosity of the porous material that test shows the present invention obtains is in the 40-80% scope.
2.3 evaluated biological activity
The porous material that the present invention is obtained is earlier after deionized water and washing with acetone, carry out external solution biological activity test after drying.Solutions employed is human body simulation body fluid (SBF; Simulated BodyFluid).SBF contains ion identical with human plasma and ionic group concentration.SBF consists of:
NaCl： 7.996g/L
NaHCO
3： 0.350g/L
KCl： 0.224g/L
K
2HPO
4.3H
2O： 0.228g/L
MgCl
2.6H
2O： 0.305g/L
HCl： 1mol/L
CaCl
2： 0.278g/L
Na
2SO
4： 0.071g/L
NH
2C(CH
2OH)
3： 6.057g/L
Porous material is in SBF, and reaction conditions vibrates in 37 ℃ of thermostat containers for the 0.15g porous material adds 30.0mL SBF solution.After respectively porous material being soaked 1,3 and 7 day, take out sample also through doing SEM, fourier infrared conversion spectrum (FTIR) and XRD test behind the deionized water wash, the result sees Fig. 3, Fig. 4, Fig. 5 respectively.Biological activity test shows that the Calucium Silicate powder porous material that the present invention obtains can generate the bone hydroxyapatite at spatial induction, thereby shows that these materials have good biological activity.
2.4 biodegradability evaluation
The porous material that the present invention is obtained is earlier after carry out the biodegradability experiment test after deionized water and washing with acetone, the oven dry.We soak degradation speed and the biodegradability that the percentage composition of the silicon that discharges after the different serial time comes evaluating material by this polyporous materials in SBF.Mix with the PEG powder of 315-630 micron as 60: 40 calcium silicate micro power of mass percent, the degradation rate of 5days just reaches 31.04% in SBF after dry-pressing formed and 1100 ℃/3h calcining, and visible porous material of the present invention has good biodegradability.
Description of drawings
In conjunction with the accompanying drawings to the detailed description that the present invention did, can understand content mentioned above by following better, wherein:
Fig. 1 is the TEM figure of the calcium silicate micro power of chemical method preparation.
Fig. 2 is the XRD figure of calcium silicate powder after 800 ℃/2h and 1100 ℃/2h calcining that chemical method prepares, and shows that material is respectively β-CaSiO at the 800 ℃/2h thing that calcining obtains with 1100 ℃/2h mutually
3And α-CaSiO
3The thing phase.
Fig. 3 is the SEM figure Calucium Silicate powder porous material of the present invention soaks preceding (A) and soaks 1 day (B) and 3 days (C) in SBF (human body simulation body fluid) after.
Fig. 4 is before Calucium Silicate powder porous material of the present invention soaks in SBF, soak Fourier transform infrared spectroscopy (FTIR) figure after 1,3 and 7 day.
Fig. 5 is that Calucium Silicate powder porous material of the present invention soaks the XRD figure after 0,1,3 and 7 day in SBF.
Fig. 3,4,5 result show that porous calcium silicate material of the present invention soaks in SBF after, on the surface of material, form the osteolith layer soon, have very strong biological activity.
Embodiment
Below by embodiments of the invention, further specify substantive distinguishing features of the present invention and marked improvement, but the present invention only is confined to embodiment by no means.
Embodiment 1:
Used starting material are as indicated above.
Get the Ca (NO of 0.4mol
3)
24H
2O is dissolved in the 1000mL deionized water, and is adjusted to about pH=13 with 1: 1 the ammoniacal liquor of 120mL, with the Na of 0.4mol
2SiO
39H
2O is dissolved in the 1000mL deionized water.The speed of pressing 2mL/min is with above-mentioned Na
2SiO
3Solution joins Ca (NO
3)
2In the solution, finish and continue to stir 12 hours, suction filtration is also removed residual Na with deionized water and dehydrated alcohol thorough washing respectively
+Ion gets wet powder, and wet powder was obtained the dry powder body in 12 hours 80 ℃ of oven dry, and ball milling was calcined 2 hours at 800 ℃ after also crossing 100 order nylon mesh screens, obtained β-CaSiO
3Micro mist.
800 ℃/2h incinerating powder is crossed 300 mesh sieves.Pressed mass ratio 60: 40, Calucium Silicate powder mixed with the PEG powder of 315-630 micron, add concentration and be 6% PVA solution and make cakingagent, transfer evenly after, dry-pressing formed under 14MPa pressure, the demoulding gets the biscuit of porous material.The calcinating system of biscuit is as follows:
The temperature rise rate of 2 ℃/min rises to 400 ℃, is incubated 2 hours, still rises to 1100 ℃ with the temperature rise rate of 2 ℃/min afterwards, and is incubated 3 hours, furnace cooling.Make the about 48MPa of ultimate compression strength of porous material of the present invention, porosity is about 54%, and thing is α-CaSiO mutually
3(Fig. 2).
The porous material of gained was soaked in the SBF simulated body fluid 1,3,5 and 7 day, and the sample after will soaking carries out biological activity and biological degradability performance evaluation.Fig. 3, Fig. 4 and Fig. 5 show that the porous biomaterial that the present invention prepares has superior bioactive.The biological degradation rate that soaked 5 days in SBF reaches 31%, shows that the bioactive ceramics that the present invention obtains has good biodegradability.
Embodiment 2:
Raw material that uses and wollastonite micropowder preparing process and embodiment 1 are together.800 ℃/2h incinerating powder is crossed 300 mesh sieves.
Get material at 50: 50 by the wollastonite and the PVA powder mass ratio of 300-600 micron and mix, get solid mixture.Preparation contains 20% AM, 2% MBAM and 8% PMAA-NH
4The aqueous solution, by volume 50: 50 ratio of per-cent is even with above-mentioned aqueous solution with the above-mentioned solid mixture of 10 grams, 2 of 3 of the ammonium persulphates of adding mass percent 3%, the TEMED of mass percent 3%, stir mobile slurry preferably, pour slurry into plastics or gypsum mold inner gel casting, and the crosslinking reaction of 60 ℃ of trigger monomers 3 hours, afterwards 100 ℃ of dryings after 12 hours the demoulding get porous material biscuit of the present invention.The calcinating system of biscuit is as follows:
The temperature rise rate of 2 ℃/min rises to 400 ℃, is incubated 2 hours, still rises to 1150 ℃ with the temperature rise rate of 2 ℃/min afterwards, and is incubated 5 hours, furnace cooling.The ultimate compression strength that makes porous material of the present invention is about 20MPa, porosity about 65%.
The performance evaluation of porous material such as embodiment 1.
Embodiment 3:
Raw material that uses and wollastonite micropowder preparing process and embodiment 1 cross 300 mesh sieves with 800 ℃/2h incinerating powder together.
Pressed mass ratio 40: 60, calcium silicate powder mixed with the PEG powder of 315-630 micron, add concentration and be 6% PVA solution and make cakingagent, transfer evenly after, dry-pressing formed under 14MPa pressure, the demoulding gets the biscuit of porous material.The calcinating system of biscuit such as embodiment 1 make the about 5MPa of ultimate compression strength of porous material of the present invention, and porosity reaches 75%.
The performance evaluation of porous material such as embodiment 1.
Claims (3)
1, a kind of preparation method of degradable porous gastrosil bioceramic material comprises and adopts chemical process to prepare β-calcium silicate micro power earlier, it is characterized in that:
(1) adding quality in β-calcium silicate micro power is 30～60% pore-forming material uniform mixing;
(2) the preparation quality is that 20% AM, quality are that 2% MBAN and quality are 5～10% PMAA-NH
4The aqueous solution, ratio with volume percent 30%～60% is even with the aqueous solution of being prepared with the compound of above-mentioned (1) then, add concentration and be the TEMED number droplet of 1～5% ammonium persulphate and 1～5%, stirring obtains flowability slurry preferably;
(3) slurry is poured into plastics or gypsum mold inner gel casting, and the crosslinking reaction of 30～80 ℃ of trigger monomers after 1～10 hour 100 ℃ of oven dry;
(4) oven dry back biscuit was 900～1400 ℃ of calcinings 1～5 hour;
(5) described pore-forming material is a kind of in polyoxyethylene glycol, polyvinyl alcohol, paraffin or polystyrene one divinyl.
(6) described β-calcium silicate micro power chemical process preparation process is with analytical pure Ca (No
3)
24H
2O, Na
2SiO
39H
2O, ammoniacal liquor and deionized water are raw material; Be mixed with the Ca (No of 1.0mol/l
3) and Na
2SiO
3The aqueous solution is with Na
2SiO
3Solution joins Ca (No
3)
2In the solution with etc. the mol ratio material reaction, finish the back continue to stir 8～24 hours, filter and remove residual Na with deionized water and dehydrated alcohol thorough washing
+, oven dry is sieved the back in 800～1000 ℃ of calcinings 1-3 hour, prepares β-calcium silicate micro power.
2, by the preparation method of the described a kind of degradable porous gastrosil bioceramic material of claim 1, it is characterized in that prepared β-calcium silicate particle is 100nm～150 μ m.
3, the porous calcium silicate biomaterial that makes by the preparation method of the described a kind of degradable porous gastrosil bioceramic material of claim 1 is characterized in that void content is 40%～80%, and the aperture is 50～500 microns.
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|---|---|---|---|---|
| WO2008017203A1 (en) * | 2006-08-01 | 2008-02-14 | Unilever Plc | Biomaterials, their preparation and use |
| CN101869724A (en) * | 2009-04-27 | 2010-10-27 | 裴国献 | Bone repair scaffold material with controlled release of traditional Chinese medicine and preparation method thereof |
| CN101700414B (en) * | 2009-11-13 | 2013-05-29 | 中国科学院上海硅酸盐研究所 | Calcium silicate nanowire/hydroxyapatite nanoparticle composite powder and preparation method thereof |
| US9149419B2 (en) | 2006-12-05 | 2015-10-06 | Conopco, Inc. | Oral care product |
| CN105645941A (en) * | 2016-01-11 | 2016-06-08 | 中国计量学院 | Preparation method of superfine porous calcium silicate ceramic membrane |
| WO2017028715A1 (en) * | 2015-08-18 | 2017-02-23 | 重庆润泽医药有限公司 | Culture device for tissue cell |
| CN109498844A (en) * | 2018-11-22 | 2019-03-22 | 北京科技大学 | A kind of method of the high compound porosity tissue scaffold design material of low cost preparation |
-
2002
- 2002-09-28 CN CN 200410058919 patent/CN1569736A/en active Pending
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2008017203A1 (en) * | 2006-08-01 | 2008-02-14 | Unilever Plc | Biomaterials, their preparation and use |
| US9149419B2 (en) | 2006-12-05 | 2015-10-06 | Conopco, Inc. | Oral care product |
| CN101869724A (en) * | 2009-04-27 | 2010-10-27 | 裴国献 | Bone repair scaffold material with controlled release of traditional Chinese medicine and preparation method thereof |
| CN101869724B (en) * | 2009-04-27 | 2014-03-26 | 裴国献 | Bone repair stent material capable of realizing controlled-release of traditional Chinese medicine and preparation method thereof |
| CN101700414B (en) * | 2009-11-13 | 2013-05-29 | 中国科学院上海硅酸盐研究所 | Calcium silicate nanowire/hydroxyapatite nanoparticle composite powder and preparation method thereof |
| WO2017028715A1 (en) * | 2015-08-18 | 2017-02-23 | 重庆润泽医药有限公司 | Culture device for tissue cell |
| CN105645941A (en) * | 2016-01-11 | 2016-06-08 | 中国计量学院 | Preparation method of superfine porous calcium silicate ceramic membrane |
| CN109498844A (en) * | 2018-11-22 | 2019-03-22 | 北京科技大学 | A kind of method of the high compound porosity tissue scaffold design material of low cost preparation |
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