波纹状银纳米线的制备及其SERS性能研究

首先通过传统的多元醇方法合成了表面光滑的银纳米线,然后利用Fe（NO₃）₃作为刻蚀剂在室温条件下对合成的银纳米线进行刻蚀得到了具有波纹状表面的银纳米线. 通过扫描电镜（SEM）分析表明：银纳米线的表面粗糙程度随着刻蚀剂量的增加而增加,但过量的刻蚀剂又会导致纳米线的断裂甚至形成球状颗粒;当刻蚀剂的量为100 μL时,获得了波纹状表面的银纳米线. 对结晶紫（CV）的表面增强拉曼光谱（SERS）结果表明,这种波纹状银纳米线的拉曼信号强度比表面光滑的银纳米线提高了约5倍,其检测限可低至10^-10 mol/L. 此外,这种优势还可以延伸到敏感性检测10^-9 mol/L的对巯基吡啶（4-Mpy）分子,可以作为一种普适、有效的SERS活性基底.     

表面增强拉曼光谱检测联苯胺

采用柠檬酸钠还原法制备了具有表面增强拉曼散射(SERS)活性的银纳米溶胶, 利用透射电子显微镜、 扫描电子显微镜和紫外-可见光谱仪对银纳米溶胶进行了表征. 对水相的联苯胺进行了SERS研究, 并对联苯胺的拉曼谱带进行了归属. 考察了团聚剂氯化镁的浓度对检测的影响, 发现随着氯化镁浓度的变大, SERS信号呈现出先增大后减弱的趋势, 即氯化镁的浓度存在一个最佳值, 此时联苯胺的检测限可达到10^-8 mol/L.     

银/金纳米线阵列表面增强拉曼基底的制备及对孔雀石绿的高灵敏度检测

利用种子介导的软模板生长方法制备了金纳米线(Au NWs)阵列, 通过调节生长温度控制Au NWs阵列的形貌, 最后在经硼氢化钠(NaBH₄)清洗过的Au NWs阵列上化学沉积银纳米颗粒(Ag NPs), 制得银/金纳米线(Ag/Au NWs)阵列作为表面增强拉曼散射(SERS)基底. 选用罗丹明6G(R6G)作为拉曼探针分子测定了Ag/Au NWs阵列的SERS性能. 结果表明, Ag/Au NWs阵列作为SERS基底具有高灵敏度、 优异的信号均匀性和良好的稳定性. 使用Ag/Au NWs阵列对孔雀石绿(MG)检测的检出限可低至1×10^-8 mol/L, 线性范围为 1×10^-8~1×10^-4 mol/L. NaBH₄可以在不影响SERS性能的情况下去除Ag/Au NWs阵列上吸附的分子, 使得 SERS基底可以重复使用. 使用Ag/Au NWs阵列对湖水中的MG进行检测, 得到了可靠的回收率, 证明Ag/Au NWs 阵列在检测环境水体中的孔雀石绿上具有应用潜力.     

手持式拉曼光谱仪结合双金属Au@AgNPs聚集体检测环境水中结晶紫

构建了一种基于手持式拉曼光谱仪,结合双金属银包金粒子(Au@AgNPs)聚集体的现场快速检测结晶紫的表面增强拉曼光谱(SERS)方法。首先制备了“核-壳”粒径分别约为30 nm和6 nm的双金属银包金粒子(Au@AgNPs),并以NaCl作为聚集剂,获得了具有SERS活性的Au@AgNPs聚集体。结合激发光源785 nm的手持式拉曼光谱仪,实现了结晶紫的快速检测。以结晶紫位于1621 cm^-1处的特征峰进行定量分析,方法检出限为8.20μg/L,对河水和湖水中结晶紫的加标回收率为71.0%～128.4%。本文所构建的方法可用于监测结晶紫的非法使用。     

超疏水性三维银纳米树SERS基底的制备及用于阿奇霉素检测

制备了一种超疏水性三维银纳米树表面增强拉曼散射(SERS)基底，利用扫描电子显微镜(SEM)、能量色散X射线光谱(EDS)及X射线衍射(XRD)对三维银纳米树进行表征，利用接触角(CA)分析其疏水性能。以罗丹明B(RB)为拉曼探针进行条件优化，并考察阿奇霉素(AZM)在该基底上的SERS性能，发现该SERS基底对AZM具有较强的拉曼增强效应，在1.0×10^-11～1.0×10^-9 mol/L范围内，AZM浓度的对数值与拉曼峰强度I_SERS呈良好的线性关系，线性拟合方程为I_SERS=4098logc+47769(R²=0.987)，检出限为4 pmol/L。使用该方法检测AZM分散片、人血清及猪血清中的AZM，加标回收率在91.2%～118.1%之间，相对标准偏差为1.1%～6.2%。     

SERS结合光谱法研究正壬酸香草酰胺与人血清白蛋白的相互作用

在模拟生理条件下,以金纳米颗粒(AuNPs)作为增强基底,归属正壬酸香草酰胺分子(OC)的表面增强拉曼光谱(SERS)特征峰,确定了其在基底表面的吸附方式.通过对比与人血清白蛋白(HSA)识别前后OC分子SERS光谱的变化情况,推测OC分子通过甲氧基与HSA进行结合,在AuNPs基底上的吸附方式也由垂直吸附转为倾斜吸附...     

SERS活性光纤光谱微探针研究

用真空蒸镀银岛膜和银溶胶自组装膜两种方法对光纤探针进行表面增强拉曼(SERS)活性修饰,构造了圆锥型SERS活性光纤光谱微探针.选取几个有代表性的分子作为检测样品,得到了低浓度样品的SERS光谱,对样品BVPP的检测下限达到10^-9mol/L.比较两种修饰光纤探针的检测结果可知,银溶胶自组装膜修饰更有优势.     

现场制备表面增强拉曼光谱基底法快速检测药片中盐酸阿米洛利的含量

利用加热贴(暖宝贴)作为热源现场合成银溶胶,并用其作为表面增强拉曼光谱(SERS)基底。使用罗丹明6G(R6G)作为探针分子,对合成的银溶胶的SERS性能进行评价。结果显示,银溶胶的制备方法简便、快速,制备时间在15 min内,具有较好的SERS增强效果,且在4 h内具有较好的稳定性。将现合成的银溶胶用于药片中盐酸阿米洛利的SERS检测,在0.8～8 mg/L范围内盐酸阿米洛利的质量浓度与拉曼峰强度有较好的线性相关系,线性方程为:y=1 395ρ-76.40,r~2=0.999 2。检出限(LOD)为0.2 mg/L,其加标回收率为104%～106%,相对标准偏差为0.35%～3.5%。该方法简单快速、稳定性好,为药片中盐酸阿米洛利的快速检测和鉴别提供了新途径。     

基于MOF@TiN-Ag/银溶胶复合基底的茶碱表面增强拉曼检测

以制备的MOF@TiN-Ag/银溶胶复合基底为表面增强拉曼光谱(SERS)活性基底，对茶碱进行SERS检测，探讨了基于该复合基底的表面增强拉曼技术在药物检测方面的应用。首先，利用电化学阳极氧化结合氨气还原氮化法制备了氮化钛纳米管阵列，随后通过电化学沉积法制备TiN-Ag复合基底，并在其表面原位生长金属有机框架(MOF)包覆层得到MOF@TiN-Ag复合基底，将茶碱与银溶胶混合后滴加在该复合基底上进行表面增强拉曼光谱检测。结果表明，MOF@TiN-Ag/银溶胶复合基底中存在面心立方晶型TiN、金属单质Ag和MOF钴基3种物相；扫描电镜结果显示，TiN纳米管排列整齐，Ag纳米结构呈树枝状均匀分散在其表面；作为隔绝层的MOF粒子形状规整，覆盖在TiN-Ag表面；银溶胶纳米粒子呈圆球状分布在MOF@TiN-Ag复合基底表面。由于银纳米粒子与TiN-Ag复合基底可发生协同增强作用，加之MOF的富集特性，使得该复合基底具有优异的SERS性能，其对茶碱溶液的SERS检出限为1×10^-5 mol/L，检测性能良好。所制备的MOF@TiNAg/银溶胶复合基底拓宽了SERS在药物检测...     

树枝状银微纳结构的表面增强拉曼散射效应研究

利用两电极电化学沉积法制备出一种树枝状银微纳结构基体.扫描电子显微镜(SEM)的表征结果证实所制备的银基体呈现出完整的树枝状结构,具有对称性的树枝和树干,且树叶清晰可见.实验结果表明,树枝状银微纳结构的表面增强拉曼散射(Surface-enhanced Raman scattering,SERS)可以检测到超低浓度的罗丹明6G(Rhodamine 6G,R6G,10-10 mol/L)光谱信号,即树枝状银微纳结构作为SERS基体表现出较好的灵敏性;当R6G的浓度在10-5~10-10 mol/L范围依次降低一个数量级时,谱带610 cm-1处的拉曼散射强度的相对标准偏差分别为12.1%,12.0%,11.7%,10.9%,13.2%和14.3%,表明所制备银基体的SERS"热点"(Hot spots)分布较均一,树枝状银微纳结构作为SERS基体具有较好的重现性;当低SERS活性的3-巯基丙酸(3-Mercaptopropionic acid,3MPA)的检测浓度为10-5 mol/L时,利用树枝状银基体能检测到3MPA的SERS光谱,说明所制备的银基体对低活性物质也具有较好的SERS灵敏性.     

Solid-liquid-liquid extraction as an approach to the sensitive detection of a hydrophobic pollutant through surface-enhanced Raman spectroscopy

Surface-enhanced Raman scattering (SERS) spectra of thiram (tetramethylthiuram disulfide), a dimethyl dithiocarbamate fungicide, were recorded after the adsorption on plasmonic silver nanowires from a system of water, organic solvent and nanoparticles. As organic solvents dichloromethane and 1-octanol were involved. A method for measuring the adsorption constant of thiram as a model molecule to the silver surface by studying its partition phenomena in a binary solvent system is presented. The method is based on the extraction of a hydrophobic molecule from an organic solvent by an aqueous suspension of silver anisotropic nanoparticles. The obtained results demonstrate the effectiveness of SERS methodology for the sensitive analysis of compounds with low aqueous solubility, and a reliable SERS spectrum of thiram was obtained with excellent signal/noise ratio at low concentrations. In addition, for vibrational assignments, Density Functional Theory (DFT) was used for the simulation of the Raman and SERS spectra of thiram and its complexes with silver considering the following two models: a single silver atom and an Ag₂₀ cluster.     

Magnetron sputtering of silver nanowires using anodic aluminum oxide template: a new active substrate of surface enhanced Raman scattering and an investigation of its enhanced mechanism

A high quality anodic aluminum oxide (AAO) template with ordered apertures about 50-80 nm was fabricated by anodizing aluminum in electrolytes through a two-step method, and silver nanowires with diameters from 40nm to 70nm were prepared on this AAO template by magnetron sputtering. On the glass covered with silver nanowires, high quality surface enhanced Raman scattering (SERS) spectra of sudan II (C₁₈H₁₆N₂O) with enhancement factors of 10⁵ were obtained. And comparison of SERS spectra on silver nanowires with the SERS spectra of silver colloids indicates that main enhanced mode is lightning rod effect of nanorods on the Sudan II/silver nanowires system.     

Polarized surface-enhanced Raman spectroscopy on coupled metallic nanowires

Regular-shaped metal nanocrystals and their ensembles can serve as ideal substrates for studying surface-enhanced Raman scattering (SERS). We synthesized well-defined silver nanowires for a systematic study of SERS signal with respect to polarization and structural ordering. The observed dependence on polarization direction confirms prior theoretical predictions that large electromagnetic (EM) fields are localized in the interstitials between adjacent nanowires. We show that these modes are largely dipolar in nature and rely on short-range EM coupling between nanowires.     

Ultrasensitive SERS Detection of TNT by Imprinting Molecular Recognition Using a New Type of Stable Substrate

We report herein a method for the ultra‐trace detection of TNT on p‐aminothiophenol‐functionalized silver nanoparticles coated on silver molybdate nanowires based on surface‐enhanced Raman scattering (SERS). The method relies on π‐donor–acceptor interactions between the π‐acceptor TNT and the π‐donor p,p′‐dimercaptoazobenzene (DMAB), with the latter serving to cross‐link the silver nanoparticles deposited on the silver molybdate nanowires. This system presents optimal imprint molecule contours, with the DMAB forming imprint molecule sites that constitute SERS “hot spots”. Anchoring of the TNT analyte at these sites leads to a pronounced intensification of its Raman emission. We demonstrate that TNT concentrations as low as 10^?12 M can be accurately detected using the described SERS assay. Most impressively, acting as a new type of SERS substrate, the silver/silver molybdate nanowires complex can yield new silver nanoparticles during the detection process, which makes the Raman signals very stable. A detailed mechanism for the observed SERS intensity change is discussed. Our experiments show that TNT can be detected quickly and accurately with ultra‐high sensitivity, selectivity, reusability, and stability. The results reported herein may not only lead to many applications in SERS techniques, but might also form the basis of a new concept for a molecular imprinting strategy.     

Ag核Au壳双金属复合纳米线的制备及其表面增强拉曼光谱研究

采用氧化铝模板结合交流电沉积技术制备纯银纳米线, 然后通过化学还原方法, 并控制加入的金盐的量, 在已制备好的银线表面包裹不同厚度的金壳层, 得到具有核壳结构的Ag_核Au_壳复合纳米线. 采用电子显微镜(SEM, TEM)和表面增强拉曼光谱对该复合结构纳米线进行相关表征, 纳米线的表面形貌与加入的金盐的量有关. 以苯硫酚(TP)和对巯基苯胺(PATP)为探针分子, 研究了此类复合纳米线的表面增强拉曼散射效应. 并以PATP在金银纳米线表面吸附的表面增强拉曼光谱的差别为探针, 表征了复合纳米线表面金的包裹程度, 结果表明一定厚度的包裹程度可制备无针孔效应的核壳结构金银复合纳米线.     

醇热法合成单晶银纳米线及其表征

以硝酸银为前驱物, 聚乙烯醇缩丁醛(PVB)为结构导向剂, 通过醇热法, 反应温度为140 ℃, 反应时间为24 h的条件下制备了银纳米线. 采用X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、热重分析(TG)、红外光谱(FT-IR)和激光拉曼光谱(Raman)等手段对产物进行了系统表征, 结果表明: 所得银纳米线具有面心立方结构, 沿着(111)晶面生长, 具有单晶结构; 考察了反应温度和时间对产物形貌的影响, 结果表明: 反应温度和时间在形成银纳米线的过程中起着关键的作用; 银纳米线具有较强的表面增强拉曼散射效应; 同时提出了银纳米线可能的晶化机理.     

Bimetallic gold–silver nanoplate array as a highly active SERS substrate for detection of streptavidin/biotin assemblies

The silver-modified gold nanoplate arrays as bimetallic surface-enhanced Raman scattering (SERS) substrates were optimized for the surface-enhanced Raman detection of streptavidin/biotin monolayer assemblies. The bimetallic gold–silver nanoplate arrays were fabricated by coating silver nanoparticles uniformly on the gold nanoplate arrays. Depending on silver nanoparticle coating, the localized surface plasmon resonance (LSPR) peak of the bimetallic gold–silver nanoplate arrays blue-shifted and broadened significantly. The common probe molecule, Niel Blue A sulfate (NBA) was used for testing the SERS activity of the bimetallic gold–silver nanoplate arrays. The SERS intensity increased with the silver nanoparticle coating, due to a large number of hot spots and nanoparticle interfaces. The platforms were tested against a monolayer of streptavidin functionalized over the bimetallic gold–silver nanoplate arrays showing that good quality spectra could be acquired with a short acquisition time. The supramolecular interaction between streptavidin (strep) and biotin showed subsequent modification of Raman spectra that implied a change of the secondary structure of the host biomolecule. And the detection concentration for biotin by this method was as low as 1.0 nM. The enhanced SERS performance of such bimetallic gold–silver nanoplate arrays could spur further interest in the integration of highly sensitive biosensors for rapid, nondestructive, and quantitative bioanalysis, particularly in microfluidics.     

线状和树枝状银纳米结构、形成机理及表面增强拉曼散射性质(英文)

以聚丙烯酰胺(PAM)为模板,在液相中通过不同浓度的抗坏血酸还原硝酸银能够得到缠结的线状和树枝状银纳米结构.该方法合成条件温和(常温常压)、产率高、成本低、操作简单,并且得到了特殊形貌的缠结收光在谱一对起线的状线和状树银枝纳状米银结纳构.米通结过构透的射形电貌子和显性微质镜进(T行E了M)表,扫征描.研电究子表显明微,镜PA(SMEM对)线、拉形曼产光物谱的和形紫成外起?可了见决吸定性作用.在反应初期,大量新生成的银核被PAM链吸附,小颗粒逐渐长大,进而相连,导致生成了缠结的线状银纳米结构.另外,抗坏血酸的浓度越高,越不利于线状结构的生成.利用对巯基苯胺(PATP)为探针分子研究了银纳米结构的表面增强拉曼散射(SERS)活性,结果表明线状银纳米结构具有较强的表面增强拉曼散射效果.     

用表面增强拉曼散射研究电解法制备的纳米银膜

用一种廉价的电解方法制备了纳米银膜,并详细研究了在这种银膜上的表面增强拉曼散射效果．结晶紫为本实验的检测性分子．通过实验发现,这种银膜用便携式拉曼光谱仪测试并计算出的表面增强拉曼散射的增强因子为603,并对结晶紫的最小检出限为0．1nmol／L．