APTES调控金纳米结构的制备

发布时间：2018-03-02 00:27

本文关键词： APTES-HAuCl4 空心金纳米壳 “碗”状硅-金纳米结构空心多孔金纳米结构　出处：《吉林大学》2017年硕士论文　论文类型：学位论文

【摘要】：金纳米粒子具有较低的毒性、良好的生物相容性及表面易功能化等特点,在生物检测、生物成像、光热治疗、靶向药物输送等方面都有着非常广阔的应用前景。通过改变粒子的尺寸、形状、长宽比、周围介质的介电常数、表面形态和粒子的聚集程度等来优化SPR(表面等离子体共振)峰的位置,进而拓宽其应用的范围。其中,空心金纳米壳是一种由可溶解的填充介质和多晶金壳组成的具有特殊性质的纳米材料。通过调节核的尺寸及壳层厚度得到不同直径的纳米粒子,所得粒子的光谱可以从可见光区调节到近红外光区,以满足生物医用等方面的应用要求。2015年本课题组研究发现,将一定浓度的APTES(氨丙基三乙氧基硅烷)分散到水中后,依次加入氯金酸水溶液、还原剂硼氢化钠以及稳定剂BSA(牛血清白蛋白),可以制备得到不同尺寸的空心金纳米壳材料,其光谱连续可调。但是,空心金纳米壳的形成机制并不清楚,单分散性也有待进一步优化。本文主要对空心金纳米壳的形成机制进行了详细研究,并在此基础上调控制备出两种不同形貌的纳米材料。本文的研究内容主要包括以下两个方面:第一,将APTES分散到水中无法形成稳定的结构,会迅速发生自催化水解;而加入氯金酸水溶液后,氨基与金之间形成配位键,最终形成稳定的单分散的APTES-HAuCl4复合物前体,这是形成空心纳米金壳的关键。然后,通过UV-Vis、TEM、DLS、FTIR等表征手段,对APTES-HAuCl4的形成条件以及自身的行为做了详细的研究。APTES/HAuCl4摩尔比R在2.83-11.33之间可以形成稳定的APTES-HAuCl4,并且R=5.67时稳定性最好。APTES-HAuCl4(APTES 8.5 mM,HAuCl4 1.5 mM)分散在水溶液中会随着时间发生变化,在40 min内,随着时间的延长前体的尺寸减小,单分散性变好,加入还原剂后可以得到空心金结构的纳米壳。最后,利用APTES-HAuCl4自身具备的特殊性质,引入一定浓度的氨水催化APTES-HAuCl4水解缩合,最终得到“碗”状硅-金纳米结构。第二,利用CTAB与APTES的协同作用制备空心多孔金纳米结构。通过改变醇水比(1:19-6:14)对粒子的尺寸及光谱性质进行调控,随着乙醇体积的增加等离子体共振峰从600 nm红移到750 nm,对应的尺寸从34.2 nm增加到84.2nm。并且制备的空心多孔金纳米结构具有较好的稳定性以及抗盐能力。在醇水比在1:9,2:8和3:7三个条件下合成的三种不同尺寸的空心多孔金纳米结构材料,具有一定增强拉曼信号(SERS)的性质。同时三种不同尺寸的粒子在水相中可以催化硼氢化钠还原对硝基苯胺反应,均可以在280 s内完成,具有较好的催化活性。
[Abstract]:Gold nanoparticles have low toxicity, good biocompatibility and easy surface functionalization, in biological detection, biological imaging, photothermal therapy, The target drug delivery has a very broad application prospect. By changing the particle size, shape, aspect ratio, the dielectric constant of the surrounding medium, The surface morphology and particle aggregation degree are used to optimize the position of the SPRs peak, and then to broaden the scope of its application. The hollow gold nanoshell is a special material with special properties composed of soluble filling medium and polycrystalline gold shell. By adjusting the size of the core and the thickness of the shell, different diameter nanoparticles can be obtained. The spectra of the obtained particles can be adjusted from the visible region to the near infrared region to meet the requirements of biomedical applications. In 2015, our research group found that APTES (aminopropyl triethoxysilane) was dispersed into water at a certain concentration. In turn, the hollow gold nanoshell materials of different sizes can be prepared by adding chlorgold acid aqueous solution, sodium borohydride and stabilizer BSA, the spectrum of which can be continuously adjusted. The formation mechanism of hollow gold nanoshell is not clear, and the monodispersity needs to be further optimized. In this paper, the formation mechanism of hollow gold nanoshell is studied in detail. On the basis of this, two kinds of nanomaterials with different morphologies were prepared. The main contents of this paper are as follows: first, the stable structure of APTES can not be dispersed into water, and the autocatalytic hydrolysis will occur rapidly; After the addition of chloruronic acid aqueous solution, the coordination bond between amino group and gold was formed, and finally the stable monodisperse precursor of APTES-HAuCl4 complex was formed, which was the key to the formation of hollow nanocrystalline gold shell. The formation conditions of APTES-HAuCl4 and its own behavior were studied in detail. APTES / HAuCl _ 4 molar ratio R = 2.83-11.33 could form stable APTES-HAuCl _ 4, and the stability of APTES-HAuCl _ 4 was the best when R = 5.67. The dispersion of APTES-HAuCl _ 4 in aqueous solution would change with time and within 40 min. With the prolongation of the time, the size of the precursor decreases and the monodispersity becomes better. The hollow gold nanoshell can be obtained by adding the reductant. Finally, using the special properties of APTES-HAuCl4 itself, a certain concentration of ammonia water is introduced to catalyze the hydrolysis and condensation of APTES-HAuCl4. Finally, the "bowl" silicon-gold nanostructures were obtained. Secondly, the hollow porous gold nanostructures were prepared by the synergistic action of CTAB and APTES. The size and spectral properties of the particles were regulated by changing the ratio of alcohol to water (1: 19-6: 14). With the increase of ethanol volume, the plasmon resonance peak shifted from 600 nm red to 750 nm, and the corresponding size increased from 34.2 nm to 84.2 nm. The hollow porous gold nanostructures had good stability and salt resistance. Three kinds of hollow porous gold nanostructures of different sizes synthesized under the conditions of 1: 9, 2: 8 and 3: 7, At the same time, three kinds of particles with different sizes can catalyze the reduction of p-nitroaniline by sodium borohydride in water, which can be completed in 280 s, and have good catalytic activity.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O614.123;TB383.1

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