Name: a filter-based surface enhanced raman spectroscopic assay for rapid detection of chemical contaminants
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This material is based upon work supported by the U.S. Department of Homeland Security under Grant Award Number 2010-ST-061-FD0001 through a grant awarded by the National Center for Food Protection and Defense at the University of Minnesota. Disclaimer: The views and conclusions contained in this document are those of the authors and should not be interpreted as necessarily representing the official policies, either expressed or implied, of the U.S. Department of Homeland Security or the National Center for Food Protection and Defense.

1.银纳米粒子合成15 <ol><li>溶解在100毫升的超纯水（18.2ΩU）和涡流18毫克硝酸银5秒。 </li><li>溶解在1毫升水中并涡旋27毫克柠檬酸钠二水合物，持续5秒。 </li><li>传输所有制备的硝酸银溶液到含有搅拌棒的锥形烧瓶中，并把该烧瓶上的磁热板上。加热在约350℃下用700rpm的搅拌速度在剧烈搅拌下将烧瓶（在板设定温度）。 </li><li>当煮沸后，立即添加所有制备的柠檬酸钠溶液的锥形瓶中，并离开该溶液煮沸额外25分钟，直到溶液变成褐绿色，这表明银纳米颗粒的形成。 </li><li>从热点板块中取出烧瓶，并把它放在另一个磁板（不加热），搅拌O / N在室温相同的搅拌速度，直到混合物达到一个稳定的状态，具有稳定的色彩和TRANsparency。使用紫外 - 可见分光计确定处理的银纳米粒子的吸光度如果必要的。 </li><li>稀释用超纯水的最终混合物至100ml。 </li><li>使用用Zetasizer根据制造商的协议，如果需要测量的Ag纳米颗粒的尺寸。 </li><li>转移的Ag胶体到密封容器中，用铝箔避光。如果需要的胶体可以储存在冰箱中于4-7℃下2个月。 </li></ol> 2. SERS有源滤波器膜的制备<ol><li>在100ml水中溶解2.92克氯化钠（NaCl），以使的50mM NaCl溶液。 </li><li>加入1ml的5mM的NaCl溶液加入到1毫升制备的Ag纳米颗粒的和在20rpm在章动混合器它们混合10分钟。这一步是聚集的Ag纳米颗粒成银纳米簇。 </li><li>滤膜（PVDF，0.1微米孔径大小）放入一个过滤器保持器，其可附连到注射器中。较小的孔径的膜为FOUND比诱捕银纳米团簇，并产生一致的信号，较大孔径的膜（即0.22微米）更有效。 </li><li>负载2毫升制备的Ag纳米团簇到注射器过滤。过滤器保持器连接到注射器，并通过该膜以1滴/秒的流速手动传递的Ag团簇的整个体积。膜陷阱的Ag纳米簇，形成了SERS活性滤膜。 </li><li>从分离的过滤器支架滤膜。用一对镊子的，以确保在膜没有损坏保持在所述外轮缘的膜时需要特别小心。空气干燥载玻片上约3分钟，并发生膜。 </li><li>拉曼检测的SERS基质的<ol><li>拉曼仪器设定为780nm的波长的激光与5毫瓦，的2.1秒和曝光数设置微观目标为10X曝光时间的激光功率。确保软件上的目标是相应地设置了。&lt;/ LI&gt; <li>放置在顶部的膜的玻璃载片上的拉曼仪器的平台，并使用显微镜聚焦在膜的表面上。 </li><li>随机选择从膜表面8-10点，仪器会自动按顺序收集它们。在制造商的软件进行分析开放光谱数据。 </li></ol></li></ol>为了检测化学污染物3. SERS有源滤波器系统中的应用<ol><li>准备一个10 ppb的福美铁的解决方案。 注意:福美铁是极不稳定。使用注意事项（口罩，护目镜）称重固体时。 <ol><li>称量2mg的福美铁粉末和将其溶解在20毫升50％的乙腈（10毫升乙腈和10毫升水），以使储液（100 ppm的）。 VORTEX烧瓶，持续30秒。 </li><li>取1毫升的100ppm福美铁溶液的试管中，并添加9毫升50％乙腈作10ppm的溶液。涡流管，持续5秒。 </li><li>取1毫升的在试管中10ppm的溶液，并添加9毫升50％乙腈作1ppm的溶液。涡流管，持续5秒。 </li><li>取1毫升1 ppm的溶液的试管中，并添加9毫升50％乙腈作为100ppb溶液。涡流管，持续5秒。 </li><li>取1毫升100ppb的溶液的试管中，并添加9毫升50％乙腈作10ppb的溶液。涡流管，持续5秒。 </li></ol></li><li>准备1 ppm的氨苄青霉素的解决方案。 <ol><li>称重10毫克氨苄青霉素粉末和将其溶解在100毫升水至100 ppm的氨苄青霉素溶液。 VORTEX烧瓶，持续30秒。 </li><li>取1毫升的100ppm溶液的试管中，并可加9个毫升水中做出10ppm的氨苄青霉素溶液。涡流管，持续5秒。 </li><li>取1毫升10ppm的溶液的试管中，并可加9个毫升水中，制成1 ppm的氨苄青霉素溶液。涡流管，持续5秒。 </li></ol></li><li>把过滤膜回过滤器保持器，与NP涂覆面朝上。&lt;/ LI&gt; <li>负载5毫升单样品到一个新的注射器，然后将其附加到与银涂覆的隔膜内的过滤器保持器。 </li><li>手动穿过膜以1滴/秒的流速通过样品的整个体积。靶分子可以吸附并浓缩到涂在过滤器膜上的纳米颗粒。 </li><li>分离从过滤器保持器，空气干燥滤膜约3分钟，并用使用相同的方法，在步骤2.6中所述的拉曼仪器测量的信号。 </li><li>重复步骤2.2至2.6，制备另一银涂层的薄膜，并从步骤3.3用于检测其他样品的遵循。 </li></ol>

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The authors have nothing to disclose.

其中一个在这个协议中的关键步骤是银纳米粒子合成，其中统一银纳米粒子是一致的结果的关键。加热时间和前体的浓度必须被精确地控制。此AGNPS制备的平均粒径为80纳米，它是由激光粒度仪测得的（数据未显示）。另一个关键步骤是该盐聚合，其中盐的浓度和聚合时间必须精确地控制。此外，膜的选择也是关键的，因为具有较小的孔径的膜被发现更有效的捕集的Ag纳米团簇。在这项研究中所用?...

表面增强拉曼光谱（SERS）是拉曼光谱与纳米技术相结合的技术。在贵金属的金属纳米表面分析物的拉曼散射的强度是由局域型表面等离子体共振大大增强。1银纳米颗粒（银纳米颗粒）是目前最广泛使用的SERS衬底 ​​，由于其高的增强能力。2截止到目前，银纳米颗粒的各种合成方法已被开发出来。3-6的Ag纳米颗粒可单独使用作为有效的SERS衬底 ​​，或与其它材料和结构组合，以提高其敏感性和/或功能性。7-11 SERS技术已经证明用于检测食品和环境样品的各种微量污染物的容量大12传统上，存在用于制备SERS样品两种常用方法:溶液和基于基片的方法13的 基于溶液的方法具D使用NP胶体与样品混合。然后将NP-分析物复合使用离心收集，并沉积到干燥后的拉曼测定的固体载体上。基于基板的方法，通常是通过沉积液体试样的数微升到预制固体基材施加14然而，无论是这两种方法都是大量的样品体积的有效和适用的。所述SERS测定的几种修饰克服了体积限制，例如作为集成过滤器系统15-21的或微流体装置的掺入21-24的改性SERS测定表明，在灵敏度和可行性极大增强用于监测化学污染物在大型水样。 在这里，我们证明制造和注射过滤器基于SERS方法的应用程序的详细的协议来检测农药福美铁和抗生素氨苄青霉素的微量。

<table><tbody><tr><td>Ampicillin</td><td>Fisher Scientific</td><td>BP1760-5</td><td>N/A</td></tr><tr><td>Ferbam</td><td>Chem Service</td><td>N-11970-250MG</td><td>98+%</td></tr><tr><td>Silver nitrate</td><td>Sigma Aldrich</td><td>209139</td><td>99.0+%</td></tr><tr><td>Sodium citrate dehydrate</td><td>Sigma Aldrich</td><td>W302600</td><td>99+%</td></tr><tr><td>Sodium chloride</td><td>Sigma Aldrich</td><td>S7653</td><td>99.5+%</td></tr><tr><td>EMD Millipore Durapore PVDF Membrane Filters</td><td>Fisher Scientific</td><td>VVLP01300</td><td>0.10 &amp;micro;m Pore Size, hydrophilic</td></tr><tr><td>Polycarbonate Filter Holders</td><td>Cole-Parmer</td><td>EW-29550-40</td><td>13 mm diameter</td></tr><tr><td>Analog Vortex Mixer</td><td>Fisher Scientific</td><td>02-215-365</td><td>N/A</td></tr><tr><td>Nutating Mixers</td><td>Fisher Scientific</td><td>05-450-213</td><td>N/A</td></tr><tr><td>DXR Raman spectroscope</td><td>Thermo Scientific</td><td>IQLAADGABFFAHCMAPB</td><td>Laser power: 1 mW&lt;br /&gt; Exposure time: 5 sec</td></tr></tbody></table>

a filter-based surface enhanced raman spectroscopic assay for rapid detection of chemical contaminants

We demonstrate a method to fabricate highly sensitive surface-enhanced Raman spectroscopic (SERS) substrates using a filter syringe system that can be applied to the detection of various chemical contaminants. Silver nanoparticles (Ag NPs) are synthesized via reduction of silver nitrate by sodium citrate. Then the NPs are aggregated by sodium chloride to form nanoclusters that could be trapped in the pores of the filter membrane. A syringe is connected to the filter holder, with a filter membrane inside. By loading the nanoclusters into the syringe and passing through the membrane, the liquid goes through the membrane but not the nanoclusters, forming a SERS-active membrane. When testing the analyte, the liquid sample is loaded into the syringe and flowed through the Ag NPs coated membrane. The analyte binds and concentrates on the Ag NPs coated membrane. Then the membrane is detached from the filter holder, air dried and measured by a Raman instrument. Here we present the study of the volume effect of Ag NPs and sample on the detection sensitivity as well as the detection of 10 ppb ferbam and 1 ppm ampicillin using the developed assay.

本实验的主要步骤的示意图（图1）中被示出。 图2展示了重要性以使用在膜包衣AGNPS的优化量以达到最大化灵敏度。 1毫升的Ag纳米颗粒的使用福美铁时提供最强信号相比，至0.5毫升（涂层不足）或2毫升（太多涂层）。 我们能够为1ppm以极大的信号强度由开发基于滤波器的SERS测定（ 图1）来...

Watch this Scientific Journal Video about A Filter-based Surface Enhanced Raman Spectroscopic Assay for Rapid Detection of Chemical Contaminants at JoVE.com

A Filter-based Surface Enhanced Raman Spectroscopic Assay for Rapid Detection of Chemical Contaminants

一种用于制造和执行增强拉曼光谱（SERS）法检测化学污染物（如农药福美铁和氨苄青霉素）的基于过滤器表面的程序提出。

基于过滤器的表面增强拉曼光谱检测方法的化学污染物快速检测

We demonstrate a method to fabricate highly sensitive surface-enhanced Raman spectroscopic (SERS) substrates using a filter syringe system that can be ...

a-filter-based-surface-enhanced-raman-spectroscopic-assay-for-rapid

Research

JoVE Journal

Chemistry

9.3K 次观看.  University of Massachusetts Amherst. 一种用于制造和执行增强拉曼光谱（SERS）法检测化学污染物（如农药福美铁和氨苄青霉素）的基于过滤器表面的程序提出。 

视频: A Filter-based Surface Enhanced Raman Spectroscopic Assay for Rapid Detection of Chemical Contaminants

Fabricating a UV-Vis and Raman Spectroscopy Immunoassay Platform

Immunoassays are used to detect proteins based on the presence of associated antibodies. Because of their extensive use in research and clinical settings, a large infrastructure of immunoassay instruments and materials can be found. For example, 96- and 384-well polystyrene plates are available commercially and have a standard design to accommodate ultraviolet-visible (UV-Vis) spectroscopy machines from various manufacturers. In addition, a wide variety of immunoglobulins, detection tags, and blocking agents for customized immunoassay designs such as enzyme-linked immunosorbent assays (ELISA) are available.
Despite the existing infrastructure, standard ELISA kits do not meet all research needs, requiring individualized immunoassay development, which can be expensive and time-consuming. For example, ELISA kits have low multiplexing (detection of more than one analyte at a time) capabilities as they usually depend on fluorescence or colorimetric methods for detection. Colorimetric and fluorescent-based analyses have limited multiplexing capabilities due to broad spectral peaks. In contrast, Raman spectroscopy-based methods have a much greater capability for multiplexing due to narrow emission peaks. Another advantage of Raman spectroscopy is that Raman reporters experience significantly less photobleaching than fluorescent tags1. Despite the advantages that Raman reporters have over fluorescent and colorimetric tags, protocols to fabricate Raman-based immunoassays are limited. The purpose of this paper is to provide a protocol to prepare functionalized probes to use in conjunction with polystyrene plates for direct detection of analytes by UV-Vis analysis and Raman spectroscopy. This protocol will allow researchers to take a do-it-yourself approach for future multi-analyte detection while capitalizing on pre-established infrastructure.

Nanoparticle-based optical probes have been designed as a vehicle for detecting antigens using Raman and UV-Vis spectroscopy. Here we describe a protocol for preparing such probes for a UV-Vis/Raman spectroscopy immunoassay in such a way to incorporate future multiplexing capabilities.

制造的UV-Vis和拉曼光谱免疫平台

Immunoassays are used to detect proteins based on the presence of associated antibodies. Because of their extensive use in research and clinical settings, ...

科研

生物化学

Surface Enhanced Raman Spectroscopy Detection of Biomolecules Using EBL Fabricated Nanostructured Substrates

Fabrication and characterization of conjugate nano-biological systems interfacing metallic nanostructures on solid supports with immobilized biomolecules is reported. The entire sequence of relevant experimental steps is described, involving the fabrication of nanostructured substrates using electron beam lithography, immobilization of biomolecules on the substrates, and their characterization utilizing surface-enhanced Raman spectroscopy (SERS). Three different designs of nano-biological systems are employed, including protein A, glucose binding protein, and a dopamine binding DNA aptamer. In the latter two cases, the binding of respective ligands, D-glucose and dopamine, is also included. The three kinds of biomolecules are immobilized on nanostructured substrates by different methods, and the results of SERS imaging are reported. The capabilities of SERS to detect vibrational modes from surface-immobilized proteins, as well as to capture the protein-ligand and aptamer-ligand binding are demonstrated. The results also illustrate the influence of the surface nanostructure geometry, biomolecules immobilization strategy, Raman activity of the molecules and presence or absence of the ligand binding on the SERS spectra acquired.

We describe the fabrication and characterization of nano-biological systems interfacing nanostructured substrates with immobilized proteins and aptamers. The relevant experimental steps involving lithographic fabrication of nanostructured substrates, bio-functionalization, and surface-enhanced Raman spectroscopy (SERS) characterization, are reported. SERS detection of surface-immobilized proteins, and probing of protein-ligand and aptamer-ligand binding is demonstrated.

表面增强拉曼光谱检测生物分子利用EBL装配纳米衬底

Fabrication and characterization of conjugate nano-biological systems interfacing metallic nanostructures on solid supports with immobilized biomolecules ...

工程学

Preparation and Application of a New Bacterial Biosensor for the Presumptive Detection of Gunshot Residue

MicRoboCop is a biosensor that has been designed for a unique application in forensic chemistry. MicRoboCop is a system made up of three devices that, when used together, can indicate the presence of gunshot residue (GSR) by producing a fluorescence signal in the presence of three key analytes (antimony, lead, and organic components of GSR). The protocol describes the synthesis of the biosensors using Escherichia coli (E. coli), and the analytical chemistry methods used to evaluate the selectivity and sensitivity of the sensors. The functioning of the system is demonstrated by using GSR collected from the inside of a spent cartridge casing. Once prepared, the biosensors can be stored until needed and can be used as a test for these key analytes. A positive response from all three analytes provides a presumptive positive test for GSR, while each individual device has applications for detecting the analytes in other samples (e.g., a detector for lead contamination in drinking water). The main limitation of the system is the time required for a positive signal; future work may involve studying different organisms to optimize the response time.

A protocol is presented using synthetic biology techniques to synthesize a set of bacterial biosensors for the analysis of gunshot residue, and to test the functioning of the devices for their intended use using fluorescence spectroscopy.

一种用于射击残留量推定检测的新型细菌生物传感器的研制与应用

MicRoboCop is a biosensor that has been designed for a unique application in forensic chemistry. MicRoboCop is a system made up of three devices that, ...

化学

Multiplex Chemical Imaging Based on Broadband Stimulated Raman Scattering Microscopy

Stimulated Raman scattering (SRS) microscopy is a nonlinear optical technique for label-free chemical imaging. This analytical tool delivers chemical maps at high speed, and high spatial resolution of thin samples by directly interrogating their molecular vibrations. In its standard implementation, SRS microscopy is narrowband and forms images with only a single vibrational frequency at a time. However, this approach not only hinders the chemical specificity of SRS but also neglects the wealth of information encoded within vibrational spectra. 
These limitations can be overcome by broadband SRS, an implementation capable of extracting a vibrational spectrum per pixel of the image in parallel. This delivers hyperspectral data that, when coupled with chemometric analysis, maximizes the amount of information retrieved from the specimen. Thus, broadband SRS improves the chemical specificity of the system, allowing the quantitative determination of the concentration of the different constituents of a sample. Here, we report a protocol for chemical imaging with broadband SRS microscopy, based on a home-built SRS microscope operating with a custom differential multichannel-lock-in amplifier detection. It discusses the sample preparation, alignment of the SRS apparatus, and chemometric analysis. By acquiring vibrational Raman spectra, the protocol illustrates how to identify different chemical species within a mixture, determining their relative concentrations.

We present a protocol to acquire chemical images with broadband stimulated Raman scattering (SRS) microscopy. Based on an SRS microscope that operates with differential multichannel-lock-in detection, the protocol describes the sample preparation, adjustment of the SRS apparatus, and chemometrics to disentangle different constituents of chemically heterogeneous samples.

基于宽带受激拉曼散射显微镜的多重化学成像

Stimulated Raman scattering (SRS) microscopy is a nonlinear optical technique for label-free chemical imaging. This analytical tool delivers chemical maps ...

Direct Comparison of Hyperspectral Stimulated Raman Scattering and Coherent Anti-Stokes Raman Scattering Microscopy for Chemical Imaging

Stimulated Raman scattering (SRS) and coherent anti-Stokes Raman scattering (CARS) microscopy are the most widely used coherent Raman scattering imaging technologies. Hyperspectral SRS and CARS imaging offer Raman spectral information at every pixel, which enables better separation of different chemical compositions. Although both techniques require two excitation lasers, their signal detection schemes and spectral properties are quite different. The goal of this protocol is to perform both hyperspectral SRS and CARS imaging on a single platform and compare the two microscopy techniques for imaging different biological samples. The spectral focusing method is employed to acquire spectral information using femtosecond lasers. By using standard chemical samples, the sensitivity, spatial resolution, and spectral resolution of SRS and CARS in the same excitation conditions (i.e., power at the sample, pixel dwell time, objective lens, pulse energy) are compared. The imaging contrasts of CARS and SRS for biological samples are juxtaposed and compared. The direct comparison of CARS and SRS performances would allow for optimal selection of the modality for chemical imaging.

This paper directly compares the resolution, sensitivity, and imaging contrasts of stimulated Raman scattering (SRS) and coherent anti-Stokes Raman scattering (CARS) integrated into the same microscope platform. The results show that CARS has a better spatial resolution, SRS gives better contrasts and spectral resolution, and both methods have similar sensitivity.

高光谱受激拉曼散射与相干反斯托克斯拉曼散射显微镜在化学成像中的应用的直接比较

Stimulated Raman scattering (SRS) and coherent anti-Stokes Raman scattering (CARS) microscopy are the most widely used coherent Raman scattering imaging ...

用电化学方法分析单个纳米颗粒的异质性能

Tracking Electrochemistry on Single Nanoparticles with Surface-Enhanced Raman Scattering Spectroscopy and Microscopy

Studying electrochemical reactions on single nanoparticles is important to understand the heterogeneous performance of individual nanoparticles. This nanoscale heterogeneity remains hidden during the ensemble-averaged characterization of nanoparticles. Electrochemical techniques have been developed to measure currents from single nanoparticles but do not provide information about the structure and identity of the molecules that undergo reactions at the electrode surface. Optical techniques such as surface-enhanced Raman scattering (SERS) microscopy and spectroscopy can detect electrochemical events on individual nanoparticles while simultaneously providing information on the vibrational modes of electrode surface species. In this paper, a protocol to track the electrochemical oxidation-reduction of Nile Blue (NB) on single Ag nanoparticles using SERS microscopy and spectroscopy is demonstrated. First, a detailed protocol for fabricating Ag nanoparticles on a smooth and semi-transparent Ag film is described. A dipolar plasmon mode aligned along the optical axis is formed between a single Ag nanoparticle and Ag film. The SERS emission from NB fixed between the nanoparticle and the film is coupled into the plasmon mode, and the high-angle emission is collected by a microscope objective to form a donut-shaped emission pattern. These donut-shaped SERS emission patterns allow for the unambiguous identification of single nanoparticles on the substrate, from which the SERS spectra can be collected. In this work, a method for employing the SERS substrate as a working electrode in an electrochemical cell compatible with an inverted optical microscope is provided. Finally, tracking the electrochemical oxidation-reduction of NB molecules on an individual Ag nanoparticle is shown. The setup and the protocol described here can be modified to study various electrochemical reactions on individual nanoparticles.

作者聚焦:使用表面增强拉曼散射光谱和显微镜跟踪单个纳米颗粒的电化学  

The protocol describes how to monitor electrochemical events on single nanoparticles using surface-enhanced Raman scattering spectroscopy and imaging.

用表面增强拉曼散射光谱和显微镜跟踪单个纳米颗粒的电化学

Studying electrochemical reactions on single nanoparticles is important to understand the heterogeneous performance of individual nanoparticles. This ...

通过激光烧蚀合成纳米颗粒和纳米结构

Ultrafast Laser-Ablated Nanoparticles and Nanostructures for Surface-Enhanced Raman Scattering-Based Sensing Applications

The technique of ultrafast laser ablation in liquids has evolved and matured over the past decade, with several impending applications in various fields such as sensing, catalysis, and medicine. The exceptional feature of this technique is the formation of nanoparticles (colloids) and nanostructures (solids) in a single experiment with ultrashort laser pulses. We have been working on this technique for the past few years, investigating its potential using the surface-enhanced Raman scattering (SERS) technique in hazardous materials sensing applications. Ultrafast laser-ablated substrates (solids and colloids) could detect several analyte molecules at the trace levels/mixture form, including dyes, explosives, pesticides, and biomolecules. Here, we present some of the results achieved using the targets of Ag, Au, Ag-Au, and Si. We have optimized the nanostructures (NSs) and nanoparticles (NPs) obtained (in liquids and air) using different pulse durations, wavelengths, energies, pulse shapes, and writing geometries. Thus, various NSs and NPs were tested for their efficiency in sensing numerous analyte molecules using a simple, portable Raman spectrometer. This methodology, once optimized, paves the way for on-field sensing applications. We discuss the protocols in (a) synthesizing the NPs/NSs via laser ablation, (b) characterization of NPs/NSs, and (c) their utilization in the SERS-based sensing studies.

作者聚焦:通过液体中的激光烧蚀进行纳米颗粒合成的进展和应用 

Ultrafast laser ablation in liquid is a precise and versatile technique for synthesizing nanomaterials (nanoparticles [NPs] and nanostructures [NSs]) in liquid/air environments. The laser-ablated nanomaterials can be functionalized with Raman-active molecules to enhance the Raman signal of analytes placed on or near the NSs/NPs.

超快激光烧蚀纳米颗粒和纳米结构在基于表面增强拉曼散射的传感应用中的应用

The technique of ultrafast laser ablation in liquids has evolved and matured over the past decade, with several impending applications in various fields ...

基于过滤器的表面增强拉曼光谱检测方法的化学污染物快速检测

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此视频中的章节

制造的UV-Vis和拉曼光谱免疫平台

表面增强拉曼光谱检测生物分子利用EBL装配纳米衬底

一种用于射击残留量推定检测的新型细菌生物传感器的研制与应用

基于宽带受激拉曼散射显微镜的多重化学成像

高光谱受激拉曼散射与相干反斯托克斯拉曼散射显微镜在化学成像中的应用的直接比较

用表面增强拉曼散射光谱和显微镜跟踪单个纳米颗粒的电化学

用表面增强拉曼散射光谱和显微镜跟踪单个纳米颗粒的电化学

超快激光烧蚀纳米颗粒和纳米结构在基于表面增强拉曼散射的传感应用中的应用

超快激光烧蚀纳米颗粒和纳米结构在基于表面增强拉曼散射的传感应用中的应用

超快激光烧蚀纳米颗粒和纳米结构在基于表面增强拉曼散射的传感应用中的应用