【作者】 何佑秋；

【导师】 刘绍璞；

【作者基本信息】 西南师范大学 ， 分析化学， 2005， 博士

【摘要】 由于物质在纳米层次上出现一系列新的物理、化学和生物特性,一些传统的分析检测技术已不再能满足研究工作的需要,急需发展新的研究方法。近年来,利用吸收光谱、荧光光谱等对纳米微粒及其反应产物的表征取得了新的进展,为纳米微粒的研究提供了有用的手段。特别是随着共振Rayleigh散射(RRS)和共振非线性散射(RNLS)分析应用的不断深入和发展,发现纳米微粒及其与某些有机化合物和生物大分子的反应产物表现出一些独特的RRS和RNLS光谱特征和分析化学性质,这就为利用这种光谱技术研究和表征纳米微粒创造了条件,也为纳米微粒在RRS和RNLS的分析应用提供了可能。共振Rayleigh散射作为一种新的分析技术得到了迅速发展。本文在国家自然科学基金的资助下,利用共振Rayleigh散射光谱并结合透射电子显微镜技术以及紫外—可见吸收光谱、荧光光谱并运用量子化学计算方法,从分子水平的层次研究金纳米微粒与有机小分子相互作用的过程、机理和结果。首先研究了金纳米微粒粒径和浓度与吸收光谱和共振Rayleigh散射和共振非线性散射光谱之间的关系,并研究了金纳米微粒与有机染料、药物和阳离子表面活性剂的相互作用。探讨了反应机理、建立了某些反应模型、讨论了共振Rayleigh散射与共振非线性散射、吸收光谱、荧光光谱之间的关系,也讨论了共振Rayleigh散射增强的原因。在此基础上,开发了直接利用金纳米微粒作探针,简便、快速、灵敏地测定某些阳离子染料、氨基糖苷类抗生素、新药雷洛昔芬以及阳离子表面活性剂的新RRS法。主要研究体系如下: 1.用吸收、共振Rayleigh散射和共振非线性散射光谱研究金纳米微粒的尺度和浓度 用柠檬酸钠还原法制备了一系列尺寸不同的金纳米微粒,并研究了金纳米微粒更多还原

【Abstract】 Substance on nano-scale, exhibit unique physical, chemical and biological characteristics, some classical analytical means can not meet satisfactorly the requirement of study and determintion, therefore there is an urgent need to develop new methods. In recent years, new progress in characterizing nanoparticle and it’s reaction product by absorption spectrum, fluorescence spectrum has been made, this provides useful means for nanoparticle study. With the development and futher study of analytical application of resonance Rayleigh scattering (RRS) and resonance non-linear scattering (RNLS), one find that nanoparticle, some organic compound and macrobiomoleule exhibit unique RRS and RNLS spectra characteristics, this made spectral analysis of this kind of technology become possible. As a new analytical method, resonance Rayleigh scattering has been developed quickly. Supported by the National Natural Science Foundation of China, this article investigates the process, mechanism and result of the reaction between the gold nanoparticles and some organic small molecular compounds at the molecule level with resonance Rayleigh scattering spectrum, and combining the transimisson electron microscope, uv-vis absorption and fluorescence spectrum and quantum chemical calculate method. First we investigated the corresponding relation between the sizes and concentrations of gold nanoparticles and spectrum of absorption, resonance Rayleigh scattering and resonance non-linear scattering. At the molecule level, then we investigated the interactions ofgold nanoparticle with some organic dye, drugs and cationic surfactants. The reaction mechanism has been inquired, and a model of the reaction has been put forward. RRS and RNLS, absorption spectrum, fluorescence spectrum, and relationship among the four spectra were investigated. The reason why RRS intensity increases greatly has been studied. Based on some simple, rapid and highly sensitive new methods for the determination of cation dye, aminoglycoside antibiotics, reloxifene (a new medicine) and cationic surfactants with gold nanoparticle as the RRS probes have been developed. Main investigated systems are listed as follow:1. A study on the sizes and concentrations of gold nanoparticles by spectra of absorption, resonance Rayleigh scattering and resonance non-linear scatteringLiquid phase gold nanoparticles with different diameters and colors can be prepared using sodium citrate reduction method by controlling the amounts of sodium citrate. The RRS, RNLS of the gold nanoparticles and the relationship between the diameters,sizes,concentrations,RRS and RNLS of the nanoparticles have been studied. The mean diameters of gold nanoparticles are measured by transmission electron microscope (TEM). Gold nanoparticles with different sizes have specific absorption spectrum. When the diameters of nanoparticles are between 12 nm and 41 nm, the maximum absorption peaks locate at 520 nm ~ 530 nm and there are bathochromic shifts gradually with the increase of diameters of gold nanoparticles. And when the size of gold nanoparticle is constant, the absorbance is proportional to the concentration of gold. Obvious resonance Rayleigh scattering (RRS) and the resonance non-linear scattering such as second-order scattering (SOS) and frequency-doubling scattering (FDS) appear at the same time as well, and the maximum scattering peaks are located at 286 nm (RRS), 480 nm (SOS) and 310 nm (FDS), respectively. When the concentration of gold is constant, absorbance, and the intensitiesof RRS, SOS and FDS (/rrs, hos and 7FDs) have linear relationships with the diameters of gold nanoparticles. When the diameter of gold nanoparticle is constant, the absorbance and /RRS, hos, ^fds are directly proportional to the concentrations of gold nanoparticles. Therefore, it is very useful for studying gold nanoparticles in the liquid phase by investigating the absorption, RRS, SOS and FDS spectra.2. Study on the interaction between gold nanoparticle and some Basic dyes by resonance Rayleigh scattering (RRS), absorption and fluorescence spectraThe interaction between gold nanoparticle and basic phenazine dye (neutral red safraine T, phenosafranine), basic phenthiazine dye (Methylene blue, Toluidine blue, Azur B) and basic phenoxazine dye (Nile blue, Meldola’s blue) has been studied with resonance Rayleigh scattering (RRS) spectrum, absorption and fluorescence spectra. In the pH 5 solution, citrate [(H2L)2*] self-assembl-es on the surface of positively-charged gold nanoparticle, which results in the [(Au)n(H2L)m]x" complex. In other words, one of carboxylate oxygen in (H2L) " moves inward and combines with gold nanoparticle. The other carboxylate oxygen moves outward to form a supermolecular complex anion with x negative charges. Then by virtue of electrostatic attraction, hydrophobic force and charge transfer action, the complex anion binds with dye cation to form a new ion-association complex. Here (H2L)2" acts as a bridge. The formation of the complex results in the significant enhancement of RRS intensity, the appearance of new RRS spectrum, the red shift of plasmon absorption band of gold nanoparticle as well as the decrease in the absorbance and fluorescence quenching for dye. In this work, the interaction between gold nanoparticle and dye on the RRS, absorption and fluorescence spectra has been investigated. The reason why RRS intensity increases greatly and the reaction mechanism have been inquired. The results show that RRS spectrum can not only be used to study nanoparticle and reaction product, but also is a sensitive means tocharacterize and detect nanparticles.The new method to detect some cationic dye(such as Methylene blue in blood serum) by RRS with the gold nanoparticle as probe has been studied and developed.3. Resonance Rayleigh scattering spectral method for the determination of some drugs and with gold nanoparticle as probe3.1 Determination of aminoglycoside antibioticsIn weak acidic medium, some aminoglycoside antibiotics, such as kanamycin (KANA), gentamicin (GEN) and tobramycin (TOB) can only produce very weak resonance Rayleigh scattering (RRS) signals, the RRS of gold nanoparticle is fairly strong, When aminoglycoside antibiotics assembles on the gold nanoparticle surface to form a supermolecular compound, RRS intensity is enhanced greatly and a new RRS spectrum appears. In a citrate containing solution, anion of citrate self-assembled on Au nanoparticle surface with positive charge, making Au nanoparticle become a supermolecular compound with negative charge surrounded by citrate. In a weak acid medium the supermolecular compound can combine with aminoglycoside antibiotics by virtue of electrostatic and hydrophobic interaction, forming aggregate with bigger diameters. The aggregate made plasmon absorption band of glod nanoparticle show evident bathochromic effect, resonance Rayleigh scattering (RRS) intensity be enhanced greatly and the resonance nonlinear scattering such as Frequency Double Scattering (FDS) and Second Order Scattering (SOS) can be increased markedly as well. In optimum conditions, there was a linear relationship between scattering intensity (A/) and the concentration of aminoglycoside antibiotics, and the highest sensitivity was RRS. So could gold nanoparticle be the RRS probe of high sensitivity for aminoglycoside antibiotics. The method has good selectivity and has been successfully applied to the detection of aminoglycoside antibiotics in clinic serum samples. In addition, the reaction mechanism and the reasons for the enhancement of RRS were discussed.3.2 Determination of reloxifeneThe first time that raloxifene hydrochloride (Ralo) marketed in America is on. March 1998, which is a kind of selective estrogen recepter modulators. The intensity of resonance Rayleigh scattering (RRS) of gold nanoparticle or Ralo is weak, but it can be enhanced significantly and a new RRS spectrum appears when both of them interact to form a supermolecular complex in acidic mediums. The intensity of RRS is directly proportional to the concentration of Ralo, So we can use RRS method to detect the content of reloxifene. This article studies the RRS spectrum character, the optimal reaction condition and the impacts among coexisting substance of this system. In another respect, this method has high sensitivity and fairly good selectivity. It’s especially simple and rapid to measure the content of Ralo which is accurately poured into former emiction, and can get a high reclaim ratio.4. Study on the interaction between gold nanoparticle and cationic surfactants by resonance Rayleigh scattering spectrum and their analytical applicationsThe interactions of gold nanoparticle with three quaternary ammonium salt cationic surfactants (CS+) such as cetylpyridinium chloridize (CPC), Zephiramine (Zeph) and cetyl trimethylammonium bromide (CTAB) have been studied by Resonance Rayleigh scattering. The experiment shows that all of them can react with gold nanoparticle which result in a significant enhancement of RRS intensity, appearance of new RRS spectrum and absorption spectrum. An neutral medium is the optimum condition for the reactions, the RRS spectral characteristics of the reaction products are similar and their maximum scattering wavelengths ( X max) have slightly difference, 369 nm (Au-Zeph), 369 nm (Au-CPC), 341 nm (Au-CTAB) respectively. The intensities of RRS at X max of the complexes are directly proportional to the concentrations of CS+ in a certain range. The method has更多还原