本文關(guān)鍵詞： 多元醇法 Fe_3O_4 介晶 磁共振成像造影劑　出處：《青島科技大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：近年來,磁性Fe_3O_4納米顆粒由于其獨特的物理化學(xué)特性,被廣泛應(yīng)用在生物醫(yī)用,環(huán)境保護(hù),信息存儲,新能源等眾多領(lǐng)域。而Fe_3O_4納米顆粒的性質(zhì)與其形貌結(jié)構(gòu)有很大關(guān)系,不同結(jié)構(gòu)形貌尺寸的Fe_3O_4顆粒往往表現(xiàn)出十分不同的性能,因此制備不同形貌尺寸的Fe_3O_4納米顆粒是實現(xiàn)其多種應(yīng)用的關(guān)鍵。介晶結(jié)構(gòu)的納米顆粒由于其特殊的結(jié)構(gòu)以及其特殊結(jié)構(gòu)所帶來的物理化學(xué)特性在最近吸引了眾多科學(xué)工作者的研究。目前,關(guān)于制備Fe_3O_4介晶顆粒的方法理論仍處于發(fā)展階段,在介晶形成機(jī)理以及其應(yīng)用上的許多方面還有待進(jìn)一步深入研究,因此,本論文主要研究了介晶Fe_3O_4在多元醇體系中的制備以及其生長機(jī)理,并研究了其磁共振成像性質(zhì),論文主要包括以下內(nèi)容:1、采用多元醇法,利用只含有氯化鐵、氫氧化鈉、水、乙二醇的簡單體系,成功制備出了Fe_3O_4介晶顆粒,研究了鐵離子濃度、氫氧化鈉的用量,水的用量等反應(yīng)參數(shù)對產(chǎn)物形貌、尺寸等性質(zhì)的影響。結(jié)果表明,氫氧化鈉的用量對最終是否獲得Fe_3O_4物相影響較大,只有在氫氧化鈉的用量與鐵離子含量符合化學(xué)計量比3/1左右的情況下,反應(yīng)最終才能得到高質(zhì)量的純Fe_3O_4顆粒。通過在能生成Fe_3O_4顆粒的范圍內(nèi)調(diào)控反應(yīng)液的p H值,能夠在一定范圍內(nèi)實現(xiàn)Fe_3O_4顆粒的尺寸調(diào)控。其次,水在該體系中也是必不可少的重要原料,在無水條件下,反應(yīng)最終得不到Fe_3O_4物相,并且,通過調(diào)控水的加入量,也能在一定范圍內(nèi)調(diào)控Fe_3O_4顆粒的尺寸大小。另外,改變反應(yīng)原料的混合方式可以顯著改變產(chǎn)物的形貌尺寸,分別能得到多孔單晶類型以及小顆粒有序聚集體類型的介晶顆粒。2、對多元醇體系中的介晶Fe_3O_4的生長過程進(jìn)行了深入研究。研究結(jié)果表明,Fe_3O_4在多元醇體系中的形成為非經(jīng)典結(jié)晶過程,當(dāng)所有原料混合均勻后,三價鐵離子首先水解,生成無定形的鐵的氫氧化物與乙二醇的復(fù)合物,之后,隨著反應(yīng)溫度的升高,乙二醇溶液的還原能力開始增強(qiáng),部分三價鐵開始被還原成二價鐵,生成了橢圓形片狀結(jié)構(gòu)的鐵醇鹽。隨著反應(yīng)溫度的繼續(xù)增加以及反應(yīng)時間的推移,越來越多的三價鐵被還原成二價鐵,二價鐵離子吸附在片狀鐵醇鹽表面并將電子傳遞給醇鹽內(nèi)部三價鐵離子,使其還原成二價鐵,當(dāng)醇鹽內(nèi)部的二價鐵離子累積到一定程度,醇鹽會局部溶解并結(jié)晶成核形成2 nm左右的Fe_3O_4初級顆粒,由于初級粒子表面富含羥基并結(jié)合了大量水分子,其性質(zhì)與微乳液類似,一旦醇鹽發(fā)生解體,可自由運動的Fe_3O_4初級顆粒為了降低體系的表面能,會自發(fā)聚集,形成較大的聚集體,隨后聚集體內(nèi)部的初級粒子會沿晶體學(xué)取向方向自發(fā)轉(zhuǎn)動,并通過脫水消除固液界面,進(jìn)一步降低系統(tǒng)的總能量,形成有序的介晶結(jié)構(gòu)。由于溶液的p H值及體系中的羧酸根離子的存在會影響二價鐵離子在醇鹽表面的吸附及Fe_3O_4初級粒子的表面電荷,對Fe_3O_4初級粒子的形核及團(tuán)聚過程有直接的影響,對從而最終影響產(chǎn)物的形貌尺寸。3、制備出了超順磁性多孔Fe_3O_4介晶顆粒,利用多聚磷酸鈉修飾其表面,使其穩(wěn)定的單分散于溶液中。研究了該種介晶顆粒作為磁共振造影劑的性能,發(fā)現(xiàn)其具有較強(qiáng)的T2磁共振弛豫增強(qiáng)能力(r2值為435.16 mM-1 s-1),良好的生物相容性,并且在小鼠的肝臟和腎臟內(nèi)具有高效快速的造影增強(qiáng)性能,是一類高效的T2型磁共振造影劑。
[Abstract]:In recent years, the magnetic Fe_3O_4 nanoparticles because of its unique physical and chemical characteristics, has been widely used in biomedical, environmental protection, information storage, new energy and other fields. There is a great relationship between properties and morphology of Fe_3O_4 nanoparticles, Fe_3O_4 particles of different size and shape structure often shows the performance is very different, so preparation of Fe_3O_4 nanoparticles with different morphology size is the key to realize its various applications. Nanoparticles mesomorphic structure because of its special structure and special structure caused by the physical and chemical properties in recent research has attracted many researchers. At present, the theory about the preparation method of Fe_3O_4 dielectric crystal particles is still in the stage of development in many ways, mesocrystal formation mechanism and its application remains to be further study. Therefore, this paper mainly studies the mesogenic Fe_3O_4 in polyol In the system of the preparation and the growth mechanism, and to study the magnetic resonance imaging properties, the main contents are as follows: 1 by polyol method using only containing ferric chloride, sodium hydroxide, water, simple system of ethylene glycol, successfully prepared Fe_3O_4 crystal particles, the iron ion concentration, sodium hydroxide the amount on the morphology of reaction parameters such as quantity of water, the influence of size and other properties. The results showed that the amount of sodium hydroxide on the final phase of Fe_3O_4 is affected only in the amount of iron ions and sodium hydroxide in stoichiometric 3/1. Reaction to obtain pure Fe_3O_4 particles with high quality. By adjusting the reaction solution p value in the range of H can generate Fe_3O_4 particles, can realize the size control of Fe_3O_4 particles in a certain range. Secondly, the water in the system is also essential The important raw materials, under anhydrous conditions, the reaction will end up getting the Fe_3O_4 phase, and, by adding water volume control, also can be in a certain range to control the size of the Fe_3O_4 nanoparticles size. In addition, the mixed mode change of reaction materials can significantly change the morphology and size of products, which can get the mesogenic.2 particles porous single crystal the type of small particles and aggregates type, the growth process of the mesogenic Fe_3O_4 polyol in the system were studied. The results show that the Fe_3O_4 formation in the polyol system in a non classical crystallization process, when the raw materials are mixed evenly, ferric ion is first hydrolyzed, after complex formation no amorphous iron hydroxide and ethylene glycol, with the reaction temperature, the reduction ability of ethylene glycol solution began to increase, some trivalent iron began to be reduced to two valent iron, generate elliptical Ferrite structure. With the reaction temperature and reaction time on continue to increase, more and more ferric iron was reduced to two iron, two iron ions in the adsorption of flake iron alkoxide and the electron transfer to the surface alkoxide internal ferric ion, it reduced to two iron, when the price of two iron alkoxide internal accumulated to a certain extent, alcohol salt will dissolve and local Fe_3O_4 primary particle nucleation formed about 2 nm, the primary particles are hydroxyl groups on the surface and the combination of a large number of water molecules, the properties of emulsion and similar, once the alkoxide and Fe_3O_4 primary particles in order to reduce the freedom of movement system of surface energy, spontaneous aggregation, formation of large aggregates, then primary particles inside the aggregates along the crystallographic orientation direction of spontaneous rotation, and through the elimination of dehydration of solid-liquid interface, to further reduce the total energy of the system, form A mesomorphic structure orderly. Due to the presence of carboxylate ions in solution P and H value in the system will affect the surface charge of two valent iron ions in the alkoxide surface adsorption and Fe_3O_4 primary particles, directly affects the nucleation and agglomeration of Fe_3O_4 primary particles, which ultimately affect the morphology and size of.3 the product, prepared superparamagnetic Fe_3O_4 porous dielectric crystal particles, using sodium polyphosphate modified on the surface, the stability of the single dispersed in solution was studied. The mesomorphic properties of particles as magnetic resonance contrast agent, we find that it has T2 strong magnetic resonance relaxation enhancement ability (R2 = 435.16 mM-1 s-1), good biocompatibility, and has a fast and efficient performance in contrast enhancement of liver and kidney, is a kind of high efficient T2 type magnetic resonance contrast agent.

【學(xué)位授予單位】：青島科技大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：TQ138.11

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 卜凡興;都晨杰;姜繼森;;介晶的制備、性能與應(yīng)用研究[J];化學(xué)進(jìn)展;2014年01期

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本文編號：1550936