银溶胶吸附的维酶素的表面增强共振拉曼散射

获得了银溶胶吸附的维酶素的表面增强共振拉曼散射光谱(SERRS)。维酶素的水溶液加到银胶中形成银胶—维酶素络合物,可使吸收谱带在440—650nm范围出现。维酶素的组分与银溶胶发生了竞争结合,而维酶素的FAD在竞争中占优势,故吸附在银溶胶表面的维酶素的SERRS实际上是FAD的异咯嗪和腺嘌呤二核苷酸的振动光谱。在维酶素中FAD作为辅基与蛋白质相连,它与蛋白质相互作用使其拉曼谱线发生3—8cm~(-1)位移。因此SERRS技术对带发色团的蛋白质结构的研究很有用处。     

银溶胶吸附的R—藻红蛋白的表面增强共振拉曼散射

现已获得银溶胶吸附的R－藻红蛋白的表面增强共振拉曼散射（SERRS），在它的SERRS谱图上共有35根谱线，而它的拉曼光谱图仅有一个“荧光包”，所有的谱线都被这个“包”所覆盖，由于银溶胶－藻红素复合物的形成及与SERS的金属基活性表面的相互作用，该SERRS谱线增强及荧光淬灭。R－藻红蛋白是由藻红素和它周围的蛋白基质组成，但是在R－藻红蛋白的SERRS谱上仅有藻红素的一些谱线，这再一次表明在带有发色团组份的蛋白质（R－藻红蛋白）与银溶胶的结合中存在着竞争结合。发色团藻红素（PEB）是对SERRS效应负主要责任的，因此，表面增强共振拉曼散射技术对研究带发色团的蛋白质是非常有用的。     

结晶紫、碱性品红、染料1555吸附在银胶上的表面增强喇曼散射的激发波长关系

本文通过研究在不同激发波长下吸附在银胶上的结晶紫、碱性品红、染料1555的表面增强喇曼散射散射强度的变化,分析了普通喇曼散射、表面增强喇曼散射及表面增强共振喇曼散射之间的联系与不同。     

苯甲酸、邻羟基苯甲酸和对羟基苯甲酸在银胶粒中的表面增强喇曼散射

在银胶体中进行了苯甲酸、邻羟基苯甲酸(又名水扬酸)和对羟基苯甲酸的表面增强喇曼散射。得到并分析了这三种分子的增强喇曼谱。这三个分子都含有ν(C—CO₂^-)伸缩振动。水扬酸和对羟基苯甲酸是同分异构体,都含有ν(C—OH)伸缩振动,但处于不同位置上。借此我们分析了相对于表面不同距离和不同取向下的增强因子变化,并与纯电磁理论的球形颗粒模型进行了比较。发现了明显的分歧,讨论了可能的原因。还讨论了凝聚对增强因子的影响,并提出了控制胶体凝聚的可能途径。 关键词：     

KCI对银胶形态影响的电子显微镜研究

借助透射电子显微镜研究了银胶中加入KCl时对银胶的影响。发现KCl的加入引起了银原子的输运,使胶体颗粒变大,表面上覆上一层疏松原子集团。同时引起胶体发生链状凝聚。和加入吡啶引起的银胶的变化做了比较,表明KCl和吡啶对银胶的作用结果有很大差异。同时也讨论了这些差异对表面增强喇曼散射信号的影响。 关键词：     

银片上茜素的表面增强共振喇曼散射效应及模式标识

本文对吸附在经连续的氧化 还原循环(ORC)过程处理的银片衬底上的茜素的表面增强共振喇曼散射(SERRS)特性进行了研究,并对茜素SERRS谱中的振动模式做了标识.结果表明,吸附在经氧化.还原循环(ORC)处理的银片衬底上的茜素分子,其表面增强喇曼散射的强度,主要是由于最靠近银片的一层分子的增强,而第一层以外的分子贡献很小.也就是说,表面增强喇曼散射具有单层饱和效应.茜素在经ORC处理的银片上和在银镜上所显示的SERRS特征基本一致,其中有些振动模式存在小的频移,这与银片、银镜各自的表面特性有关.     

添加KCl对银胶光吸收的影响

本文研究了添加KCl对两种银胶光吸收谱的影响,并与添加吡啶的情形进行了比较。结果表明KCl的加入,由于造成银颗粒表面的覆盖层而使整个光谱区的光吸收增加,消弱了原银颗粒的等离振子共振吸收,同时因银胶发生链状凝聚,原等离振子共振吸收峰发生劈裂和红移。讨论了这些变化对表面增强喇曼散射强度的影响。 关键词：     

腺嘌呤吸附在银胶上的SERS研究

研究了腺嘌呤水溶液吸附在银胶上的表面增强喇曼散射(SERS)。除在SERS谱和普通喇曼谱不是很大差异外,观察到腺嘌呤的SERS谱与在银胶中腺嘌呤的体浓度有关。在改变腺嘌呤体浓度时,腺嘌呤环呼振动模的峰值有位移和相对峰值强度改变,把它们诠释为腺嘌另在银面上的取向有关。     

少量KCl引起水杨酸表面增强喇曼散射谱的异常变化

本文报道KCl引起的银胶中水杨酸(C₇H₄O₃)表面增强喇曼散射谱(SERS)的异常变化。发现KCl造成水杨酸分子中某些结构的SERS强度急剧而迅速下降,但同时又造成3436cm^-1附近v(—OH)振动的SERS信号的进一步增强。还研究了KCl对一系列含—COOH结构的分子(例如苯甲酸、对氨基苯甲酸等)SERS信号的影响,发现Cl^-对v(—COO^-)振动的SERS强度有明显的 关键词：     

InGaN薄膜的紫外共振喇曼散射

利用325nm紫外光激发,对不同组分的In_xGa_1-xN薄膜的喇曼散射谱进行了研究.在光子能量大于带隙的情况下,观察到显著增强的二阶A₁(LO)声子散射峰.二阶LO声子峰都从一阶LO声子的二倍处向高能方向移动,移动量随样品In组分的增加而增大,认为是带内Frhlich相互作用决定的多共振效应引起的.分析了一阶LO声子散射频率和峰型与In组分的关系.在喇曼谱中观察到样品存在相分离现象,并与X射线衍射的实验结果进行 关键词： xGa_1-xN合金')" href="#">In_xGa_1-xN合金 紫外共振喇曼散射 二阶声子 相分离     

菜粉蝶颗粒体病毒包涵体在银胶中的表面增强拉曼光谱研究

本文讨论了菜粉蝶(preris rtpae)颗粒体病毒(简称 PrGV )包涵体在银胶中的表面增强拉曼光谱。PrGV 包涵体的 SERS 谱与其 RS 谱之间存在一定对应关系。PrGV 包涵体蛋白分子通过羧基和氨基基团吸附于银粒子表面,并构成阴离子形式(NU_2RCOO~-)存在于溶液中。PrGV 在银胶中的表面增强的增强机制属于短程作用。PrGV 包涵体与银胶表面的吸附主要是化学吸附。     

纳米银对表面吸附核黄素分子光谱性质的影响

采用氧化还原法制备了纳米尺寸的银溶胶,研究了纳米银粒子对核黄素(Riboflavin,Ri)水溶液吸收光谱和荧光光谱的影响.Ri溶液中加入纳米银粒子,随着纳米银浓度的增大,吸收强度不断增强,372 nm处吸收峰红移,而444 nm处吸收峰蓝移,同时发生荧光猝灭现象.从无辐射通道增强、纳米银表面局域场减弱及Ri分子第一激...     

Ag‐nanoparticle‐modified single Ag nanowire for detection of melamine by surface‐enhanced Raman spectroscopy

Silver nanowires synthesized by a solvothermal method were used as templates for fabricating silver‐nanoparticle‐decorated silver (AgNP/Ag) nanowires. The number density and particle size of Ag nanoparticles can be controlled by varying the concentration of Ag precursor. Single AgNP/Ag nanowire exhibited strong surface‐enhanced Raman scattering effect. Detection of melamine molecules at concentrations as low as 1.0 × 10⁻⁸ M was used as an example to show the possible applications of such AgNP/Ag nanowires. Their application in rapid detection of melamine in milk solution was further demonstrated. It was shown that melamine in milk solution at a low concentration of 5.0 × 10⁻⁸ M can be easily detected with little sample pretreatment. The results demonstrate the potential of single AgNP/Ag nanowire as a surface‐enhanced Raman scattering substrate for convenient and sensitive detection of trace amounts of melamine in a complex mixture. Copyright © 2012 John Wiley & Sons, Ltd.     

Surface enhanced Raman scattering from tris (bipyridine) ruthenium (II) adsorbed on silver-modified p-GaAs

Both surface enhanced Raman scattering (SERS) and surface enhanced resonant Raman scattering (SERRS) have been observed from Ru(bpy)₃²⁺ adsorbed on p-GaAs (1 0 0) after the electrodeposition of Ag particles onto the semiconductor surface. For the enhancement factor for SERS a lower limit of 10⁴ has been determined.     

Spacer‐free SERRS spectra of unperturbed porphyrin detected at 100 fM concentration in Ag hydrosols prepared by modified Tollens method

Surface‐enhanced resonance Raman scattering (SERRS) spectroscopy is a powerful tool for the selective and sensitive detection of porphyrins. We report a repeatable detection of unperturbed free base 5,10,15,20‐tetrakis(1‐methyl‐4‐pyridyl)21H,23H‐porphine in concentrations as low as 1 × 10^–13 M in the final system when Ag nanoparticles prepared by modified Tollens method are employed as Raman scattering amplifiers, i.e. without any further post‐modifications of their surface. Most probably the residues of sugar oxidation present on Ag nanoparticle surface are responsible for the effective protection of 5,10,15,20‐tetrakis(1‐methyl‐4‐pyridyl)21H,23H‐porphine molecules against the metalation by silver. Copyright © 2011 John Wiley & Sons, Ltd.     

Comparison of SERRS and RRS excitation profiles of [Fe(tpy)2]2+ (tpy = 2,2':6',2'‐terpyridine) supported by DFT calculations: effect of the electrostatic bonding to chloride‐modified Ag nanoparticles on its vibrational and electronic structure

Nonresonance (or normal) Raman scattering (NRS), resonance Raman scattering (RRS), surface‐enhanced Raman scattering (SERS), and surface‐enhanced RRS (SERRS) spectra of [Fe(tpy)₂]²⁺ complex dication (tpy = 2,2':6',2''‐terpyridine) are reported. The comparison of RRS/NRS and SERRS/SERS excitation profiles of [Fe(tpy)₂]²⁺ spectral bands in the range of 445–780 nm is supported by density functional theory (DFT) calculations, Raman depolarization measurements, comparison of the solid [Fe(tpy)₂](SO₄)₂ and solution RRS spectra, and characterization of the Ag nanoparticle (NP) hydrosol/[Fe(tpy)₂]²⁺ SERS/SERRS active system by surface plasmon extinction spectrum and transmission electron microscopy image of the fractal aggregates (D = 1.82). By DFT calculations, both the Raman active modes and the electronic states of the complex have been assigned to the symmetry species of the D_2d point group. It has been demonstrated that upon the electrostatic bonding of the complex dication to the chloride‐modified Ag NPs, the geometric and ground state electronic structure of the complex and the identity of the three different metal‐to‐ligand charge transfer (¹MLCT) electronic transitions remain preserved. On the other hand, the effect of ion pairing manifests itself by a slight change in localization of one of the electronic transitions (with max. at 552 nm) as well as by promotion of the Herzberg–Teller activation of E modes resulting from coupling of E and B₂ excited electronic states. Finally, the very low, 1 × 10⁻¹¹ M SERRS spectral detection limit of [Fe(tpy)₂]²⁺ at 532‐nm excitation is attributed to a concerted action of the electromagnetic and molecular resonance mechanism, in conjunction to the electrostatic bonding of the complex dication to the chloride‐modified Ag NP surface. Copyright © 2014 John Wiley & Sons, Ltd.     

单个银纳米聚合体的偶极表面等离子体共振灵敏表面增强拉曼散射(英文)

pacc:5240F,7830Weinvestigatedpolarizationdependencesof surfaceenhancedresonanceRamanscattering(SERRS)andsurfaceplasmonresonance(SPR)toidentifytheSERRSyieldingSPRbands.We alsostudiedSERRSexcitationspectraforsingle Agnano-aggregateswiththeSPRbandstoex plore…     

Surface‐enhanced Raman scattering study of human serum on PVA?Ag nanofilm prepared by using electrostatic self‐assembly

Polyvinyl alcohol (PVA)‐protected silver nanoarchitecture (PVA Ag nanofilm) on the surface of the glass substrate was prepared by using electrostatic self‐assembly at a proper voltage. The two‐dimensional morphology of the PVA Ag nanofilm has been examined by scanning electron microscopy (SEM). The surface‐enhanced Raman scattering (SERS) spectra of human serum (HS) on PVA Ag nanofilms were recorded. The results show that the Raman scattering of HS can be enhanced efficiently based on these PVA Ag nanofilms. However, it also can be seen that the effect of sodium citrate (SC) acting as anticoagulant on the SERS spectrum of HS is unnegligible, which has not been discussed adequately in the previous reports. To discuss the effect of SC on the SERS spectrum of HS, we have studied the normal Raman spectra of solid SC and the SERS spectra of 1.0 × 10⁻³ mol/l aqueous solution of SC adsorbed on the PVA–Ag nanofilms. Meanwhile, Raman wavenumbers of the SC molecule were calculated by using the method of DFT‐B3LYP/6‐31G*, and the dominant assignations of the calculated wavenumbers were performed. It was found that the density functional theory (DFT) calculation of SC Raman spectrum matches well with the experimental results. With the perfect reproducibility and high SERS activity, this method will be useful in the development of HS detection methods. Copyright © 2010 John Wiley & Sons, Ltd.     

Application of calixarene to high active surface‐enhanced Raman scattering (SERS) substrates suitable for in situ detection of polycyclic aromatic hydrocarbons (PAHs) in seawater

The characteristics of the sol–gel matrix embedding Ag nanoparticles functionalized with 25,27‐dimercaptoacetic acid‐26,28‐dihydroxy‐4‐tert‐butylcalix[4]arene (DMCX) suitable for the in situ detection of polycyclic aromatic hydrocarbons (PAHs) in seawater is presented. The DMCX‐functionalized silver nanoparticles were produced by the thermal reduction method in xerogel film. The silver colloid blocks were formed in the sol–gel matrix, with a diameter ranging from 50 to 120 nm. DMCX forming the monolayer on the silver nanoparticle surface contributes to the surface‐enhanced Raman scattering (SERS) activity due to the aggregation of silver nanoparticles and the preconcentration of PAH molecules within the zone of electromagnetic enhancement. When selected, PAH molecules e.g. pyrene and naphthalene were adsorbed onto the SERS substrate; Raman band positions of PAH were slightly shifted. A calibration procedure reveals that this type of SERS substrate has a limit of detection of 3 × 10⁻¹⁰ mol/l for pyrene and 13 × 10⁻⁹ mol/l for naphthalene in artificial seawater. The Raman signal response on a pyrene concentration change in artificial seawater was evaluated using a 671‐nm Raman setup with a flow‐through cell. This type of SERS substrate will be suitable for the in situ trace detection of pollutant chemicals in seawater. Copyright © 2012 John Wiley & Sons, Ltd.     

银颗粒表面尿嘧啶分子的SERS实验研究——KCl对尿嘧啶分子吸附状态的影响

利用表面增强喇曼散射(SERS)在灰银胶体系中研究了KCl对尿嘧啶分子吸附状态的影响,并将实验结果与Oh等人在黄银胶体系中的实验结果进行了详细比较.对这一实验现象进行了定性解释.