磁性纳米探针的制备及磁共振成像应用研究

发布时间：2018-01-04 09:14

本文关键词：磁性纳米探针的制备及磁共振成像应用研究　出处：《北京化工大学》2015年硕士论文　论文类型：学位论文

【摘要】：癌症等疾病的早发现早治疗是目前科研与临床研究中的巨大挑战。许多生物医学成像技术的发展,如计算机X射线体外断层扫描术(CT),光学成像,声学成像和磁共振成像(MRI)等,已在临床医学癌症等疾病诊断中得到广泛应用。MRI由于其高分辨、无损伤、无电离辐射等优势成为强大的诊断成像技术,但高灵敏MRI成像检测需要使用性能优良的核磁共振成像对比剂。本论文主要围绕磁性纳米探针的设计合成及其磁共振成像应用开展研究。核磁共振成像造影剂不仅要有高的磁共振信号,而且需要良好的生物相容性和水溶液稳定,便于活体成像应用。以具有良好生物相容性的聚天冬氨酸(PASP)为包覆试剂,本论文通过简单的一步水热合成法成功制备了Fe3O4@PASP磁性纳米流体。合成的Fe3O4@PASP磁性纳米颗粒表面包覆的多聚氨基酸(PASP)具有丰富的羧基官能团,使得纳米粒子在水溶液中可长久稳定不沉淀,并具有好的生物偶联性,便于生物分子的偶联,可生物降解。通过调节反应温度可使磁性纳米颗粒尺寸控制在10-13nm范围内,且颗粒结晶性好、磁性强、具有高的T2加权信号响应,横向弛豫率高达302.6S-1mM-1。适用于磁共振成像(MRI)。发展了一种简便、快捷的制备核磁共振成像对比剂的新方法,所制备的磁共振成像对比剂Fe3O4@PASP横向弛豫率高、生物相容性好,便于生物医学检测应用。为进一步发展生物相容性好、可生物降解的核磁共振成像对比剂,在前期工作的基础上,以α-乳白蛋白的水解产物为功能试剂,以Ca2+和Gd3+两种金属离子共同诱导α-乳白蛋白水解产物自组装,形成具有磁响应的纳米球。通过对相应实验条件(部分水解的乳白蛋白的量、反应时间、pH值、Ca2+、Gd3+和光敏剂孟加拉红(RB)的浓度等)的调控,可以控制纳米球的尺寸与形貌。第一次将α-乳白蛋白作为载体来负载用于磁共振成像的Gd3+和用于光动力学治疗的光敏剂RB。合成的双功能纳米球具有非常好的生物相容性和很好的生物靶向性,并且表现出很好的T1加权的磁共振成像和高效的光动力学效应。发展了一种以蛋白为载体制备多功能核磁共振成像对比剂的新方法,拓展诊断治疗一体化多功能试剂研发新思路,可望用于临床诊断治疗一体化研究。
[Abstract]:Early cancer and other diseases at early treatment is a great challenge at present and clinical research in scientific research. The development of many biomedical imaging techniques, such as X ray computer tomography (CT) in vitro, optical imaging, acoustic imaging and magnetic resonance imaging (MRI), has been in clinical medicine in the diagnosis of diseases such as cancer widely the application of.MRI due to its high resolution, no damage, no ionizing radiation has become a powerful diagnostic imaging technique, but highly sensitive MRI imaging requires the use of the excellent performance of the magnetic resonance imaging contrast research. This thesis mainly focuses on the design and synthesis of magnetic nano probe and its application in magnetic resonance imaging MRI contrast agent. Have a high magnetic resonance signal, and the need for compatibility and good biological stability in aqueous solution, for in vivo imaging applications. With good biocompatibility of polyaspartic acid (PASP) as This paper coating reagent, through a simple hydrothermal method successfully prepared Fe3O4@PASP nano magnetic fluid. The synthesis of Fe3O4@PASP magnetic nanoparticles coated on the surface of poly amino acid (PASP) with carboxyl rich, the nanoparticles can be long stable without precipitation in aqueous solution, and has good biological coupling so, the coupling of biological molecules, biodegradable. By adjusting the reaction temperature can make the magnetic particle size in the range of 10-13nm, and the particles have good crystallinity and strong magnetism, with high T2 weighted signal response of the transverse relaxation rate as high as 302.6S-1mM-1. for magnetic resonance imaging (MRI). The development of a is a new method of preparation of magnetic resonance imaging contrast agent fast, the magnetic resonance imaging contrast agent Fe3O4@PASP transverse relaxation by Henan high rate, good biocompatibility and easy application in biomedical detection. Step in the development of good biocompatibility, magnetic resonance imaging contrast agent can be biodegradable, on the basis of previous work, the hydrolysis product of alpha lactalbumin as functional reagent, induced by common alpha lactalbumin hydrolysate self-assembled by Ca2+ and Gd3+ two kinds of metal ions, formed with magnetic nanoparticles. The response of the the corresponding experimental conditions (partial hydrolysis of lactalbumin amount, reaction time, pH value, Ca2+, Gd3+ and photosensitizer Rose Bengal (RB) concentration) control, can control the size and morphology of nanoparticles. The first alpha lactalbumin as the carrier to load for magnetic resonance imaging and for Gd3+ photodynamic therapy photosensitizer RB. synthesis of bifunctional nanoparticles have good biocompatibility and good biological targeting, and showed T1 weighted magnetic resonance imaging is a good and efficient photodynamic effect. The development of a A new method of preparing multifunctional magnetic resonance imaging contrast agent based on protein and expanding the new idea of diagnosis and treatment integrated multifunctional reagents is expected to be applied in the integrative research of clinical diagnosis and treatment.

【学位授予单位】：北京化工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB383.1

【共引文献】