纳米碳基磁性复合材料的制备及在磷酸钙骨水泥中的应用

发布时间：2018-04-01 10:19

本文选题：骨水泥　切入点：磁性复合材料　出处：《西南交通大学》2017年硕士论文

【摘要】：磷酸钙骨水泥(Calcium phosphate cement,CPC)具有良好的生物安全性和可塑性,因此在骨修复领域得到广泛研究。但由于其抗压强度低,常用于非承重骨部位的骨修复和骨替代,使其在临床上的应用受到很大限制。新型纳米碳材料——碳纳米管(Carbon nanotubes,CNTs)和石墨烯或还原氧化石墨烯(Reduced-graphene oxide,RGO),由于具有高比表面积、优良的力学性能、电性能等优点,是理想的增强材料。纳米四氧化三铁(Fe304)由于具有良好的磁性能、生物相容性以及材料纳米效应,作为功能性纳米粒子在生物医学磁热疗、药物靶向治疗等领域得到广泛应用。因此,将Fe304与纳米碳材料进行复合,并引入到CPC体系中,可制备出具有优良力学性能和良好磁刺激响应性的骨修复材料。本实验通过水热法在CNTs和RGO两种碳纳米材料上原位沉积Fe3O4,制备了纳米碳基磁性复合材料,并研究了不同制备方法和不同表面活性剂的添加对磁性复合材料的物化性能影响。在此基础上,将所制备的饱磁化强度较高的CNTs/Fe3O4和RGO/Fe304添加到CPC中,成功制备了磁性磷酸钙骨水泥(MCPC),并对其物化性质进行了测试。并且,在不同磁强度的静磁场作用下,深入研究添加了 CNTs/Fe3O4的MCPC在模拟体液(SBF)中的降解性能和矿化性能。通过骨髓间充质干细胞(MSCs)与MCPC的体外共培养实验,对MCPC的细胞相容性进行了评价,并探讨了不同静磁场强度的刺激对MCPC细胞相容性的影响。首先,以沸点回流法和水热法,在CNTs和RGO上沉积Fe3O4制备磁性复合材料中,发现CNTs/Fe3O4上的Fe3O4的结晶度更高,磁性更强;通过不同的表面活性剂对Fe304的结晶度、形貌以及在CNTs上的分散程度进行调控;结果表明,通过添加NaAc和CTAB组合及NaAc和PEG 2000组合的表面活性剂,制得的CNTs/Fe3O4饱和磁化强度分别达到了 65.77emu/g和65.08emu/g,处于较高水平。将不同纳米碳基磁性复合材料加入到CPC的固相粉中,成功制备了具有磁性骨水泥(MCPC)。结果表明,纳米碳基磁性复合材料的添加,对MCPC的物相组成没有影响,但会减少MCPC的凝固时间;并且,随着添加量的升高,MCPC的凝固时间显著减少。不同纳米碳基磁性复合材料对MCPC的影响不同,加入RGO/Fe3O4的MCPC呈现脆性断裂,加入CNTs/Fe3O4的MCPC具有一定的塑性,且随着CNTs/Fe3O4量的增加,MCPC先呈现出塑性断裂,随后呈现脆性断裂。并且,加入CNTs/Fe3O4的MCPC较加入RGO/Fe3O4的MCPC的抗压强度和弹性模量分别提高了 178.4%和776.5%。但CNTs/Fe3O4复合材料的添加量为9wt%时,MCPC的抗压强度和弹性模量均最高,分别达到40.15MPa和1782 MPa,相对于没有添加CNTs/Fe3O4的空白CPC(BCPC)分别提高了 83.2%和93.7%。由降解与矿化实验可知,MCPC具有良好的防溃散能力,并且在SBF浸泡过程中,β-磷酸三钙(β-TCP)向羟基磷灰石(HA)的转化持续进行。在浸泡5天后,添加了 9wt%的CNTs/Fe3O能促进MCPC中HA晶粒在(113)晶面择优生长。另外,CNTs/Fe3O4的添加,有利于提高MCPC的降解速率。在静磁场刺激下,MCPC的降解和矿化行为的最终结果不会发生变化,但会对其降解和矿化过程产生影响,主要体现在影响MCPC的降解和矿化速率上。其中,80m T静磁场的刺激,有利于提高MCPC的降解速率,300mT静磁场的刺激,有利于提高MCPC的矿化速率。通过体外细胞共培养实验可知,在无静磁场刺激时,各MCPC对MSCs细胞的增殖有抑制作用,且磁性复合材料的添加不利于MCPC上细胞胞内Ca2+的富集,磁性复合材料的不同含量对细胞的形态没有影响。在有静磁场刺激时,不同静磁场刺激对BCPC上MSCs细胞的增殖活性呈现阶段性的抑制或促进作用;60mT静磁场的刺激对MCPC上MSCs细胞的增殖活性均有较明显的促进作用,当磁性复合材料添加量为9wt%时促进作用最为明显;不同静磁场刺激均对MCPC上MSCs细胞的分化有促进作用,且在130mT静磁场作用下,当添加量为12wt%时,MCPC上MSCs细胞的分化活性最高。不同静磁场刺激均能促进MCPC上MSCs细胞的黏附和铺展。不同静磁场刺激均不利于BCPC上细胞胞内Ca2+富集,且磁强越大,富集程度越低。不同静磁场刺激均能促进磁性复合材料含量为9wt%的MCPC上细胞对Ca2+的富集,且磁强越大,富集程度越高,但促进作用存在阀值。表明MCPC对MSCs细胞的影响具有磁响应性,并且其细胞相容性具有"窗口"效应。
[Abstract]:Calcium phosphate cement (Calcium phosphate, cement, CPC) has a good biocompatibility and plasticity, so it has been widely studied in the field of bone repair. But because of its low compressive strength, commonly used in non weight bearing bone bone repair and bone substitute, so its clinical application is limited. The new nano carbon material: carbon nanotubes (Carbon, nanotubes, CNTs) and graphene or graphene (Reduced-graphene oxide RGO), because of its high surface area, excellent mechanical properties, electrical properties and other advantages, is the ideal material. Enhancement of Fe3O4 nanoparticles (Fe304) with good magnetic properties, biocompatibility and material the effect of nano, as functional nanoparticles in biomedical magnetic hyperthermia, drug targeting and other fields are widely used. Therefore, Fe304 and nano carbon composite materials, and introduced into the CPC system, Can be prepared by stimulus response of bone repair materials with excellent mechanical properties and good magnetic. The experimental hydrothermal method by CNTs and RGO in two kinds of carbon nano materials in situ deposition Fe3O4, nano carbon based magnetic composite material was prepared, and studied the effects of different preparation methods and different surfactants. Add the physicochemical properties of the composite materials. On this basis, CNTs/Fe3O4 and RGO/Fe304 with high magnetization prepared will be added to the CPC, the magnetic calcium phosphate cement (MCPC) was prepared, and its physicochemical properties were tested. Furthermore, in static magnetic field with different magnetic intensity under the in-depth study of adding CNTs/Fe3O4 MCPC in simulated body fluid (SBF) in the degradation and mineralization properties. Through bone marrow mesenchymal stem cells (MSCs) and MCPC co cultured in vitro experiments on the biocompatibility of MCPC was evaluated, and discussed. With static magnetic field stimulation compatibility effects on MCPC cells. Firstly, by boiling reflux method and hydrothermal method, CNTs and RGO on the deposition of Fe3O4 in preparation of magnetic composite materials, found on the crystallization of CNTs/Fe3O4 Fe3O4 degrees higher, stronger magnetic; by crystallization of different surfactants on the degree of Fe304, morphology and dispersion degree of CNTs in the regulation; results show that by adding surface active NaAc and CTAB and NaAc and PEG 2000 combination agent, prepared by CNTs/Fe3O4 saturation magnetization reached 65.77emu/g and 65.08emu/g, at a high level. The different carbon based magnetic composite material is added into solid powder CPC in the successful preparation of the magnetic bone cement (MCPC). The results show that the addition of nano carbon based magnetic composite materials of MCPC, the phase composition has no effect, but will reduce the setting time of MCPC; and, with the amount of Increased coagulation time was significantly reduced. MCPC effects of different nano carbon based magnetic composite materials of MCPC different, adding RGO/Fe3O4 MCPC showed brittle fracture, adding CNTs/Fe3O4 MCPC has certain plasticity, and with the increase of CNTs/Fe3O4 content, MCPC first showed ductile fracture and brittle fracture. Then the compressive strength. And the elastic modulus of MCPC was added into CNTs/Fe3O4 RGO/Fe3O4 MCPC and 776.5%. were increased by 178.4% but the amount of CNTs/Fe3O4 composites was 9wt%, compressive strength and elastic modulus of MCPC was the highest, reached 40.15MPa and 1782 MPa respectively, compared with no added CNTs/Fe3O4 blank CPC (BCPC) were increased by 83.2% and by 93.7%. degradation and mineralization experiment shows that MCPC has good ability of anti collapsibility, and SBF in the soaking process, beta tricalcium phosphate (beta -TCP) to hydroxyapatite (HA) transformed into continuous In line. After 5 days of immersion, adding 9wt% CNTs/Fe3O could promote the MCPC in the HA grain in the (113) preferred growth. In addition, the addition of CNTs/Fe3O4 can improve the degradation rate of MCPC. In the static magnetic field stimulation, the final result of MCPC degradation and mineralization behavior will not change, but the impact the degradation and mineralization process, mainly reflected in the influence of MCPC degradation and mineralization rate. Among them, 80m T static magnetic field stimulation, can improve the degradation rate of MCPC and 300mT static magnetic field stimulation, can improve the mineralization rate of MCPC. Through the experiment in vitro, in the absence of static magnetic field stimulation, inhibit the MCPC proliferation of MSCs cells, and the addition of magnetic composite materials for MCPC on the intracellular Ca2+ accumulation, did not affect the content of different forms of magnetic composite materials of cells. In a static magnetic field stimulation, different static Magnetic stimulation on BCPC MSCs cell proliferation activity showed phasic inhibition or facilitation; promote the proliferation activity of 60mT static magnetic field stimulation on MCPC MSCs cells obviously, when the magnetic composite dosage 9wt% the most obvious role; promote the stimulation of different static magnetic field of MCPC on the differentiation of MSCs cells, and the static magnetic field in 130mT, when the dosage is 12wt%, MCPC on the differentiation of MSCs cells. The highest activity of different static magnetic stimulation can promote cell adhesion and spreading of MSCs cells MCPC. Stimulation of different static magnetic field are not conducive to BCPC on the intracellular accumulation of Ca2+, and the strong magnetic the greater the enrichment, the lower degree of different static magnetic stimulation can promote the content of magnetic composite materials for the enrichment of Ca2+ 9wt% on MCPC cells, and the magnetic intensity is strong, the higher the degree of enrichment, but the role of MSCs MCPC. That there is a threshold of fine The effect of the cell is magnetic responsiveness, and its cell compatibility has a "window" effect.

【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB33;R318.08

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