癌症诊治用纳米硅质体的制备及功能研究

发布时间：2018-08-05 09:22

【摘要】：癌症是威胁人类健康和生存的重大疾病，长期以来，广大科研人员不断探索和开发各种各样的治疗方法，药物载体是其中重要的一方面，因为它可以有效地防止药物降解，将药物输送到病变区域，降低毒副作用，提高治疗效果。然而，随着时代的发展，传统药物载体逐渐暴露出了一些缺点，如稳定性差、生物相容性差、载药量低、肿瘤靶向富集少、体内循环时间短等，这些问题极大地降低了药物的生物利用度，增加了患者的痛苦，因此，迫切需要发展新型药物载体。当前，药物载体正向着可控化、智能化、绿色化和诊疗一体化的方向发展，不断涌现出了各种具有良好发展前景的新型载体。有机-无机复合载体材料就是其中的一种，它综合了有机物和无机物的特性，具备独特的优势。本文以有机无机复合材料的一种——硅质体作为研究对象，从有机-无机复合脂质分子设计的角度出发，在药物载体的结构控制释放、光控释放、光动力治疗，以及光动力治疗结合磁共振成像等方面开展了系统的研究。研究了有机无机复合脂质结构对硅质体药物释放性能的影响。通过调节脂质分子亲疏水基团的比例，合成了4种不同结构的复合脂质分子，利用溶胶凝胶和自组装技术获得了四种具有不同表层硅酸盐网络致密度的新型硅质体，并以亲水药物阿霉素和疏水药物紫杉醇为代表，成功制备了4种阿霉素硅质体和4种紫杉醇硅质体。通过体外药物释放行为和细胞毒性的对比分析，阐明了载体对药物的释放性能与相应复合脂质的结构密切相关。实验结果表明，各载体对药物均具有良好的缓释作用，当疏水基团相同时，亲水硅烷数量越多，药物的释放速率越慢；当亲水硅烷相同时，疏水基团越多，对亲水药物的释放越快，而对疏水药物的释放则越慢。细胞实验结果表明，各载药硅质体对细胞的抑制作用与其药物释放行为一致，即载体对药物的释放越快，则相同药物浓度和相同孵育时间下对细胞的抑制作用也越明显，充分体现了分子结构的设计对脂质双层渗透性的有效调控。开展了高度稳定灵敏的光响应控制释药载体材料的研究。通过有机合成的方法将光敏感基团偶氮苯与复合脂质相结合，获得了一种新型的光响应有机无机复合脂质分子，进而制备了脂质双层富含偶氮苯基团的光响应囊泡载体。通过紫外可见吸收光谱研究了囊泡中偶氮苯基团光致异构的情况，阐明了光致异构的影响因素。实验结果表明，脂质双层中偶氮苯基团与脂质双链主要以交替排列的方式分布，在紫外光和可见光轮流照射下，双层中的偶氮苯能顺利地实现可逆的构型异构，且其反-顺异构化比例可达到33.4%。以染料尼罗红作为模型药物，研究了光响应载体的光控释药性能。研究发现，在紫外光照下，载体在20min内即可释放48.2%的尼罗红，表现出灵敏的光响应控制释药能力。研制了具有光动力治疗和荧光诊断功能的硅质体。将卟啉基团引入复合脂质分子中，合成了含有双链、硅烷头部、卟啉基团的新型复合脂质，制备了相应的卟啉硅质体光动力载体材料，其光敏剂载药量可高达33.4%。通过包载亲水性染料钙黄绿素研究了卟啉硅质体的囊泡结构；通过大量的实验和讨论分析，研究了载体双层中卟啉基团的聚集和排列方式、化学共价键连卟啉基团的重要作用、单线态氧产生的情况并解释了其产生机理，探讨载体被细胞摄取的方式，并通过细胞形态变化和MTT方法研究了光动力治疗效果，在此基础上进行了初步的动物实验，考察载体在大鼠血液中的循环动力学。实验结果表明，卟啉硅质体脂质双层中卟啉基团基本不存在聚集情况，其与双链之间主要以交替方式有序排列，在紫外光照射下，载体呈现出明显的红色荧光。在重水和细胞中卟啉硅质体均能显著地产生单线态氧，且产生效率与浓度和时间成正比。激光共聚焦显微镜图片清楚地显示载体以内吞方式被肿瘤细胞摄取，且主要聚集于溶酶体中。载体对细胞表现出很低的暗毒性和显著高的光毒性，且在血液中具有长循环的特点，体现了其作为药物载体的显著优势。构建了同时具有磁共振成像与光动力治疗功能的诊疗一体化纳米粒子。在前一章合成的基础上，，将卟啉与金属锰卟啉衍生物相结合，制备了一种内有双层卟啉基团外有金属锰卟啉的新型纳米粒子，其中脂质双层中的卟啉用于光动力治疗，外层的锰卟啉用于磁共振成像。研究了该类粒子的制备方法、光谱性质、单线态氧产生效率、细胞摄取实验，并在此基础上进行体外磁共振成像效果和光动力治疗效果的检测。实验结果表明，所制备的纳米粒子在透射电镜下呈现明显的核壳结构，通过调节5种不同比例的外层锰卟啉，可制备出光动力治疗和磁共振成像效果可调节的纳米粒子，随着键连锰卟啉比例的增加，粒子对水质子的纵向驰豫效率加速也越明显，达到40.1%以上时，成像效果达到最佳。细胞实验证实了该纳米粒子能被肿瘤细胞有效摄取，且对细胞具有低暗毒性和高光毒性，最终能同时满足成像和光动力治疗的纳米粒子上键连锰卟啉的最佳比例是40.1%。
[Abstract]:Cancer is a major disease that threatens the health and survival of human beings. For a long time, the vast majority of researchers have been exploring and developing a variety of treatment methods. Drug carriers are one of the important aspects of it, because it can effectively prevent drug degradation, transport drugs to the lesion area, reduce toxic and side effects and improve the therapeutic effect. However, along with it, it can improve the therapeutic effect. With the development of the times, traditional drug carriers have gradually exposed some shortcomings, such as poor stability, poor biocompatibility, low drug loading, low tumor targeting and short circulation time in the body. These problems greatly reduce the bioavailability of drugs and increase the pain of the patients. Therefore, the development of new drug carriers is urgently needed. Current, drugs The carrier is developing in the direction of controllability, intelligence, green and diagnosis and treatment. A variety of new carriers with good prospects are emerging. Organic inorganic composite carrier is one of them, which combines the characteristics of organic and inorganic materials and has unique advantages. This paper is an organic and inorganic composite material. From the perspective of organic-inorganic compound lipid molecules, the systematic research on the structure control release, light control release, photodynamic therapy, photodynamic therapy combined with magnetic resonance imaging is carried out from the perspective of organic-inorganic compound lipid molecules.
The effect of organic-inorganic compound lipid structure on the drug release performance of siliceous body was studied. By adjusting the proportion of hydrophobic groups of lipid molecules, 4 kinds of composite lipid molecules with different structures were synthesized. By using sol-gel and self-assembly technology, four new types of silicosomes with different surface silicates density were obtained, and the hydrophilic group was hydrophilic. 4 kinds of doxorubicin and 4 taxol silicones were successfully prepared with drug doxorubicin and taxol, a hydrophobic drug paclitaxel. The release performance of the drug and the structure of the corresponding compound lipid were closely related to the drug release behavior and cytotoxicity in vitro. When the hydrophobic group is the same, the more the hydrosilane number is, the more the drug release rate is, the more the hydrophile silane phase, the more hydrophobic groups, the faster the release of hydrophilic drugs, and the slower the release of hydrophobic drugs. The faster the release of the drug, the more obvious the inhibitory effect of the same drug concentration and the same incubation time on the cells, which fully reflects the effective regulation of the molecular structure design on the lipid bilayer permeability.
A highly stable and sensitive light response controlled release carrier material was studied. A novel light responsive organic inorganic compound lipid molecule was obtained by combining the light sensitive group azobenzene with the compound lipid by organic synthesis, and the light response vesicle carrier rich in the azobenzene group in the lipid bilayer was prepared. The photoisomerization of azobenzene group in the vesicles was studied by the external visible absorption spectrum, and the influence factors of photoisomerism were clarified. The experimental results showed that the azobenzene group and the double chain of lipid in the lipid bilayer were mainly distributed in an alternately arranged way. The azobenzene in the double layer could be reversible in the ultraviolet and visible light wheel flow. The structure isomerism, and its inverse isomerization ratio can reach 33.4%. with dye Nile red as a model drug. The photocontrolled release performance of light response carrier is studied. It is found that under ultraviolet light, the carrier can release 48.2% Nile red in 20min, showing the sensitive light response to control the drug release ability.
A siliceous body with the function of photodynamic therapy and fluorescence diagnosis was developed. The porphyrin group was introduced into the compound lipid molecule, and a new compound lipid containing double chain, silane head and porphyrin group was synthesized. The corresponding porphyrin siliceous photodynamic carrier material was prepared. The dosage of the photosensitizer could be as high as 33.4%. by carrying the hydrophilic dye calcium. The vesicle structure of porphyrin siliceous body was studied by yellowish green. Through a large number of experiments and discussions, the aggregation and arrangement of porphyrin groups in the carrier double layer, the important role of the chemical covalent bond group, the production of single wire oxygen and the mechanism of its production were explained. Morphological changes and MTT methods were used to study the effect of photodynamic therapy. On this basis, a preliminary animal experiment was carried out to investigate the circulation kinetics of the carrier in the rat blood. The experimental results showed that the porphyrin group in the porphyrin siliceous lipid bilayer had no aggregation, which was arranged alternately and orderly between the double strands. Under ultraviolet light, the carrier shows a clear red fluorescence. In heavy water and cells, the porphyrin silicates can produce a single state of state oxygen significantly, and the production efficiency is proportional to the concentration and time. The laser confocal microscope picture clearly shows that the carrier is absorbed by the tumor cells and mainly in the lysosome. Cells exhibit low dark toxicity and significant high phototoxicity, and have a long circulation in the blood, reflecting its significant advantages as a drug carrier.
An integrated nanoparticle with magnetic resonance imaging and photodynamic therapy was constructed. On the basis of the previous chapter, porphyrin and manganese porphyrin derivative were combined to prepare a new type of nanoparticle with metal manganese porphyrin with bilayer porphyrin group. The porphyrin in the lipid bilayer was used for photodynamic treatment. Treatment, manganese porphyrin on the outer layer used in magnetic resonance imaging. The preparation methods of such particles, spectral properties, single state oxygen production efficiency, cell uptake experiments, and the detection of the magnetic resonance imaging effect and photodynamic treatment effect in vitro were carried out on this basis. The experimental results showed that the prepared nanoparticles were obvious under transmission electron microscope. The nuclear shell structure can be prepared by adjusting 5 different proportions of the outer manganese porphyrin, which can prepare the nanoparticles with the effect of photodynamic therapy and magnetic resonance imaging. With the increase of the ratio of manganese porphyrins, the acceleration of the longitudinal relaxation efficiency of the particles to the water protons is also more obvious. The imaging results are best at the time of 40.1%. Cell experiments confirmed that The nanoparticles can be effectively absorbed by the tumor cells and have low dark toxicity and high phototoxicity to the cells. The optimal ratio of the nanoparticles to manganese porphyrin at the same time can meet the imaging and photodynamic therapy is 40.1%.
【学位授予单位】：哈尔滨工业大学
【学位级别】：博士
【学位授予年份】：2012
【分类号】：R318.08

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