多级结构石墨烯—羟基磷灰石杂化材料制备及其应用研究
发布时间：2018-10-05 21:33
【摘要】：石墨烯(Graphene)作为新兴的二维材料,具有优异的电性能、导热性能、机械性能、极大的表面积,在光电材料、有机染料的吸附和生物医学等领域受到广泛的关注和研究。然而,石墨烯的片层之间存在很强的范德华力,导致石墨烯易团聚,很难以单片层稳定存在,在与聚合物共混时,难以均匀分散;此外,石墨烯本身缺乏特定的生物活性,这些问题在一定程度上限制了石墨烯在纳米复合材料和生物医学的运用。羟基磷灰石(HA)作为一种天然的无机盐,主要存在于动物的骨结构中。有难溶于水、生物可降解及骨诱导等优点。HA作为吸附剂以及生物医用材料都有广泛的应用,但是纳米HA易团聚、脆性大、裂韧性差等缺点限制了其实际运用。聚乳酸作为一种重要的生物高分子材料,在组织工程中具有重要应用;但是聚乳酸其机械强度较低、韧性差、结晶速率较低。一种理想的骨组织工程支架材料,其不仅需具有良好的骨传导性和骨诱导性,而且必须具有良好的生物相容性和机械强度及可塑性。围绕上述问题,本论文主要开展了以下研究:1.碱性条件下,在氧化石墨烯片层表面原位生长纳米羟基磷灰石,可以实现原位还原氧化石墨烯,获得石墨烯-羟基磷灰石(RGO-HA)杂化材料,负载的羟基磷灰石能够有效抑制石墨烯片层之间的π-πstacking作用,实现还原氧化石墨烯和羟基磷灰石的协同分散。使用红外光谱(FT-IR)、透射电镜(TEM)、X射线衍射(XRD)、X射线电子能谱分析(XPS)、拉曼光谱等测试表征RGO-HA杂化材料。RGO-HA杂化材料作为吸附剂,进行吸附动力学、等温吸附和pH值对吸附的影响研究。实验结果表明:1、RGO-HA对有机染料的吸附过程包含物理吸附和化学吸附;2、RGO-HA吸附剂表层吸附位点吸附能力相同且分布均匀;3、RGO-HA吸附剂更适用于阳离子有机染料的吸附,在碱性条件下吸附能力呈现急剧上升趋势。2.先制备表面接枝聚(右旋乳酸)的RGO-HA(RGO-HA-g-PDLA),再通过静电纺丝技术制备载有辛伐他汀(SIM)的RGO-HA-g-PDLA/PLLA复合纳米纤维支架材。将制备的含有辛伐他汀(SIM)的RGO-HA-g-PDLA/PLLA的纳米纤维膜按照SIM浓度由高向低卷成圆柱状,接着吸附I型胶原、并利用戊二醛溶液作为交联剂,对支架材料进行交联,最后将其切成薄片支架材料植入雄性BALB/c小鼠颅骨进行修复。体外矿化实验结果表明制备的RGO-HA-g-PDLA/PLLA@SIM支架材料相对于PLLA、PLLA@SIM和RGO-HA-g-PDLA/PLLA具有更好的钙沉积能力。体外药物释放结果表明RGO-HA-g-PDLA/PLLA纤维膜中的SIM有效释放时间高达30天,相对于PLLA支架材料有更持久有效的释放,SIM的释放量高达88%,颅骨的修复实验结果表明RGO-HA-g-PDLA/PLLA@SIM支架材料具有更强的促进骨组织修复能力。
[Abstract]:Graphene (Graphene), as a new two-dimensional material, has been widely studied in the fields of optoelectronic materials, adsorption of organic dyes and biomedicine due to its excellent electrical properties, thermal conductivity, mechanical properties and great surface area. However, there is a strong van der Waals force between the layers of graphene, which leads to easy agglomeration of graphene, which makes it difficult for monolayer to exist stably and is difficult to disperse uniformly when mixed with polymer. In addition, graphene itself lacks specific biological activity. These problems limit the application of graphene in nanocomposites and biomedicine to some extent. Hydroxyapatite (HA), as a natural inorganic salt, mainly exists in the bone structure of animals. Ha is widely used as adsorbent and biomedical material in water, biodegradability and bone induction. However, nano-sized HA is easy to agglomerate, brittle and poor fracture toughness, which limits its practical application. Polylactic acid (PLA), as an important biomaterial, has important applications in tissue engineering, but its mechanical strength, toughness and crystallization rate are low. An ideal scaffold for bone tissue engineering should not only have good bone conductivity and bone induction, but also have good biocompatibility, mechanical strength and plasticity. Around the above question, this thesis mainly carried out the following research: 1. Nano-hydroxyapatite was grown on the surface of graphene oxide in situ under alkaline condition. In situ reduction of graphene and hydroxyapatite (RGO-HA) hybrid material could be achieved. The supported hydroxyapatite can effectively inhibit the 蟺-蟺 stacking interaction between the graphene lamellae and realize the synergistic dispersion of reduced graphene and hydroxyapatite. The adsorption kinetics, isothermal adsorption and the effect of pH value on the adsorption of RGO-HA hybrid material. RGO-HA hybrid material were characterized by infrared spectroscopy (FT-IR), transmission electron microscopy (TEM) (TEM) X-ray diffraction (XRD) X-ray electron spectroscopy (XRD) and Raman spectroscopy (XPS),). The adsorption kinetics, isothermal adsorption and the effect of pH value on the adsorption were studied. The experimental results show that the adsorption process of organic dyes by RGO-HA includes physical adsorption and chemical adsorption. The adsorption ability of RGO-HA on the surface layer of RGO-HA is the same, and the RGO-HA adsorbent is more suitable for the adsorption of cationic organic dyes. The adsorption capacity showed a sharp upward trend under alkaline conditions. Surface grafted RGO-HA (RGO-HA-g-PDLA) was prepared, and then RGO-HA-g-PDLA/PLLA composite nanofiber scaffold containing simvastatin (SIM) was prepared by electrostatic spinning. The prepared RGO-HA-g-PDLA/PLLA nanofiber membrane containing simvastatin (SIM) was rolled into columns according to the concentration of SIM from high to low. Then collagen I was adsorbed, and glutaraldehyde solution was used as crosslinking agent to cross-link the scaffold. Finally, a thin slice of the scaffold was implanted into the skull of male BALB/c mice for repair. The results of in vitro mineralization test showed that the prepared RGO-HA-g-PDLA/PLLA@SIM scaffold had better calcium deposition ability than that of PLLA,PLLA@SIM and RGO-HA-g-PDLA/PLLA. The results of drug release in vitro showed that the effective release time of SIM in RGO-HA-g-PDLA/PLLA fiber membrane was up to 30 days. Compared with PLLA scaffold material, the release amount of SIM was as high as 88%. The results of skull repair experiment showed that RGO-HA-g-PDLA/PLLA@SIM scaffold material had a stronger ability to promote bone tissue repair.
【学位授予单位】：南昌大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB332
本文编号：2254941
[Abstract]:Graphene (Graphene), as a new two-dimensional material, has been widely studied in the fields of optoelectronic materials, adsorption of organic dyes and biomedicine due to its excellent electrical properties, thermal conductivity, mechanical properties and great surface area. However, there is a strong van der Waals force between the layers of graphene, which leads to easy agglomeration of graphene, which makes it difficult for monolayer to exist stably and is difficult to disperse uniformly when mixed with polymer. In addition, graphene itself lacks specific biological activity. These problems limit the application of graphene in nanocomposites and biomedicine to some extent. Hydroxyapatite (HA), as a natural inorganic salt, mainly exists in the bone structure of animals. Ha is widely used as adsorbent and biomedical material in water, biodegradability and bone induction. However, nano-sized HA is easy to agglomerate, brittle and poor fracture toughness, which limits its practical application. Polylactic acid (PLA), as an important biomaterial, has important applications in tissue engineering, but its mechanical strength, toughness and crystallization rate are low. An ideal scaffold for bone tissue engineering should not only have good bone conductivity and bone induction, but also have good biocompatibility, mechanical strength and plasticity. Around the above question, this thesis mainly carried out the following research: 1. Nano-hydroxyapatite was grown on the surface of graphene oxide in situ under alkaline condition. In situ reduction of graphene and hydroxyapatite (RGO-HA) hybrid material could be achieved. The supported hydroxyapatite can effectively inhibit the 蟺-蟺 stacking interaction between the graphene lamellae and realize the synergistic dispersion of reduced graphene and hydroxyapatite. The adsorption kinetics, isothermal adsorption and the effect of pH value on the adsorption of RGO-HA hybrid material. RGO-HA hybrid material were characterized by infrared spectroscopy (FT-IR), transmission electron microscopy (TEM) (TEM) X-ray diffraction (XRD) X-ray electron spectroscopy (XRD) and Raman spectroscopy (XPS),). The adsorption kinetics, isothermal adsorption and the effect of pH value on the adsorption were studied. The experimental results show that the adsorption process of organic dyes by RGO-HA includes physical adsorption and chemical adsorption. The adsorption ability of RGO-HA on the surface layer of RGO-HA is the same, and the RGO-HA adsorbent is more suitable for the adsorption of cationic organic dyes. The adsorption capacity showed a sharp upward trend under alkaline conditions. Surface grafted RGO-HA (RGO-HA-g-PDLA) was prepared, and then RGO-HA-g-PDLA/PLLA composite nanofiber scaffold containing simvastatin (SIM) was prepared by electrostatic spinning. The prepared RGO-HA-g-PDLA/PLLA nanofiber membrane containing simvastatin (SIM) was rolled into columns according to the concentration of SIM from high to low. Then collagen I was adsorbed, and glutaraldehyde solution was used as crosslinking agent to cross-link the scaffold. Finally, a thin slice of the scaffold was implanted into the skull of male BALB/c mice for repair. The results of in vitro mineralization test showed that the prepared RGO-HA-g-PDLA/PLLA@SIM scaffold had better calcium deposition ability than that of PLLA,PLLA@SIM and RGO-HA-g-PDLA/PLLA. The results of drug release in vitro showed that the effective release time of SIM in RGO-HA-g-PDLA/PLLA fiber membrane was up to 30 days. Compared with PLLA scaffold material, the release amount of SIM was as high as 88%. The results of skull repair experiment showed that RGO-HA-g-PDLA/PLLA@SIM scaffold material had a stronger ability to promote bone tissue repair.
【学位授予单位】：南昌大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB332
【参考文献】
相关期刊论文 前1条
1 江国栋;常青;杨福福;胡晓允;唐和清;;超声辅助合成磁性四氧化三铁/氧化石墨烯复合物及其在染料去除中的应用（英文）[J];Chinese Journal of Chemical Engineering;2015年03期
，本文编号：2254941
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