表面增强拉曼光谱检测爆炸物研究进展

近年来,恐怖袭击、刑事犯罪等爆炸事件频发,对社会的公共安全构成了严峻挑战。炸药是各种爆炸物的核心成分,因此对炸药的分析检测与识别是公共安全领域研究的热点之一。表面增强拉曼光谱可以对爆炸物分子实现指纹谱性、超痕量、实时高效的探测和识别,在安全检测和法庭科学等公共安全领域展现了极具诱惑力的应用前景。最近几年,国际上针对表面增强拉曼光谱检测爆炸物的研究十分活跃,取得了丰富的成果,文章综述了爆炸物表面增强拉曼基底,包括表面修饰改性和复合功能结构基底;有机和无机爆炸物的检测;以及爆炸物光谱识别的研究进展。分析了需要面对的问题,并总结展望了未来的发展趋势。相信随着纳米科学与技术、表面科学、仪器科学以及深度学习等新兴科技的快速发展,表面增强拉曼光谱一定能在爆炸物检测和识别方面取得更大进展。     

爆炸物、毒品的标准拉曼谱图库的建立及自动检索系统

采集31种爆炸物和73种毒品的标准拉曼谱图,分析其谱图,选出适合作为搜索条件的光谱范围。通过编程,建立标准拉曼谱图库和自动检索系统。在选定光谱范围内,拉曼谱图库选择信号较强的特征峰,进行曲线拟合,将获得的峰位置、相对峰强等数据作为参数写入标准拉曼谱图库。通过自动检索系统将未知拉曼光谱与数据库中的标准谱图进行分析比对,搜索软件自动给出正确结论。数据库具有添加、删除、备份、恢复等辅助功能,并具有自动扣除荧光背底,优化拉曼光谱图等功能。本文进一步分析了可能对分析比对结果造成影响的因素。     

多波长消荧光拉曼光谱仪的研制及应用研究

拉曼光谱技术作为探究分子、晶体及其结构特征的有力手段,具有快速、无损、样品用量小、无需前处理且适应性强等优点,已被广泛应用于食品安全、石油化工等领域。但在拉曼光谱应用中,常常受到荧光背景干扰,导致拉曼信号降低,严重的情况下拉曼信号甚至会淹没在荧光背景中。为解决拉曼技术在实际应用中荧光背景干扰的问题,从仪器角度出发,采用二色镜对多波长拉曼光谱进行光路耦合设计,研制了近红外拉曼光谱与移频差分拉曼复合一体的多波长消荧光拉曼光谱检测系统,其中近红外拉曼光谱采用1 064 nm激光光源设计,移频差分拉曼光谱选取784.5和785.5 nm两组激光光源进行时分复用,在移频差分拉曼光谱检测的同时,亦可获得两组单波长拉曼光谱数据。通过对比同步测试和分时逐次测试的强度及峰位稳定性,验证了多波长消荧光拉曼光谱仪的同步测试性能;选取了多种荧光背景强弱不同的样品,进行了单波长拉曼、近红外拉曼及移频差分拉曼光谱的对比分析。针对丙酮、乙腈等荧光背景较弱的样品,可采用单波长拉曼光谱对样品进行定量及定性分析;针对食用油、红色塑胶微粒等荧光背景与拉曼信号强度相当的样品,可采用近红外拉曼光谱对样品进行定量及定性分析;针对红酒、棕色塑胶微粒等荧光背景较强的样品,需结合近红外拉曼光谱和差分拉曼光谱对样品进行定性分析。研究表明：通过多波长消荧光拉曼光谱检测系统的研制,在常规单波长拉曼光谱技术的基础上,将两种抑制荧光干扰技术有机结合,有效扩充了应用领域及样品检测范围。     

拉曼光谱技术的应用及研究进展

本文简述了拉曼光谱产生的机理以及与红外光谱的区别,讨论了拉曼光谱在聚合物、生物分子、蛋白质和无机物等方面研究及应用,介绍了傅立叶变换拉曼、共焦显微拉曼、表面增强激光拉曼、固体光声拉曼光谱的原理及其应用以及拉曼光谱和其他检测手段的联用技术。     

表面增强拉曼光谱快速检测毒品海洛因

荧光的干扰使得毒品海洛因难以直接进行拉曼光谱检测。本文将表面增强拉曼散射(SERS)技术引入到毒品海洛因的快速检测,首次获得它的表面增强拉曼特征峰。采用此法成功检测了来自海关的20批毒品海洛因样品,对其它粉末的检测中没有出现误报现象。这表明表面增强拉曼光谱可用于对海洛因的准确检测。     

近红外拉曼光谱快速检测地榆

采用先进的共焦显微拉曼光谱仪,测试了地榆的拉曼光谱,绘出地榆拉曼一阶导数谱。地榆拉曼光谱中,在155、195、902、1466、1476cm-1等处出现明显的特征峰。地榆拉曼谱的一阶导数谱,在152,192,900,157,197,905cm-1等处出现明显特征峰。分析地榆拉曼光谱,确认主要归属与已有的地榆化学成分研究结果相符。地榆拉曼光谱及其一阶导数谱可作为地榆快速准确检测的依据。     

共振拉曼光谱技术应用综述

拉曼光谱是提供物质结信息的强有力工具。但由于拉曼散射信号弱,灵敏度低,因此应用范围受到限制。而在共振拉曼光谱(RRS)中,由于激发光源频率落在分子的某一电子吸收带内,分子吸收光子向电子激发态的跃迁变成了共振吸收,因此对入射光的吸收强度大大增加。与常规拉曼光谱相比,RRS能够提高信号强度的106倍。因此,RRS检测技术以其更高的灵敏度和选择性而具有更广的应用,特别是在生物学及医学等领域。如：(1)生物基质中的类胡萝卜素和叶绿素等色素分析;(2)细胞、蛋白质和DNA等有机物研究以及一些临床疾病诊断。RRS可以得到在常规拉曼光谱中隐藏的、更为重要的分子结构信息。RRS总是在很低的浓度下测试,且共振拉曼增强的谱线是属于产生电子吸收的基团,这对于有色物和生物样品尤为重要。因为很多这类样品的活性部位接近于生色基团,且研究对象往往是生物大分子的某一部分,所以在研究生物物质的结构和功能的关系时,RRS起着重要作用。近年来,由于光谱技术的发展使得RRS检测技术得到创新与延伸,如液芯光纤共振拉曼光谱和透射共振拉曼光谱等新技术的应用。通过对近几年有关RRS技术应用的原始论文、数据和主要观点进行归纳整理与分析提炼,介绍了RRS这一专题的历史背景和研究现状,分别对共振拉曼光谱的色素检测、生物检测和爆炸物检测等应用领域展开详细的综述,并介绍了相关新技术的发展应用。随着光谱技术的快速发展,RRS必将在科研领域拥有其他光谱技术不可取代的重要地位。     

拉曼光谱技术在食品质量安全检测中的应用

拉曼光谱技术具有样品无需前处理、操作简便、时间短、灵敏度高等优点,可获得样品的物理化学及深层结构信息,已广泛应用于石油化工、生物医学、地质考古、刑事司法、宝石鉴定等领域。拉曼光谱对水等极性物质极其不敏感,在食品质量安全检测方面具有良好的应用前景。论文简述了拉曼光谱技术的检测原理、分类以及系统的组成,综述了拉曼光谱技术在食品成分分析和农药残留检测中的最新研究进展,指出了该技术在食品质量安全检测中的关键技术并对今后的研究进行了展望。     

拉曼光谱技术在农作物生理信息检测中的研究进展

拉曼光谱(Raman spectroscopy,RS)是一种散射光谱,具有样品前处理简单、响应速度快、灵敏性高以及原位无损检测等特点。由于拉曼信号具有指纹图谱特性和不受水分信息干扰的优势,其在生物体信息检测方面发挥着重要作用。拉曼光谱成像技术是拉曼光谱技术发展的新方向,其可以同时获取研究对象的空间及光谱信息;显微拉曼光谱技术不仅可以进行分子结构的检测,还能够实现生物组织微区化学成分的空间分布分析。目前,应用拉曼光谱进行农作物生理信息的检测成为学者们的研究热点。本文概述了拉曼光谱的基本原理和分类,并重点介绍了拉曼光谱技术在农作物的生殖与营养器官(种子,花朵,果实和根,茎,叶)中生理信息检测方面的国内外最新研究进展。最后结合国内外研究现状,分析了拉曼光谱在农作物生理信息检测中的局限,并对其的应用前景进行了展望。     

光谱法研究阿莫西林及其与DNA的相互作用

报道了阿莫西林对照品与阿莫西林胶囊的常规拉曼光谱(NRS)和在银胶基底上溶液的表面增强拉曼光谱(SERS),归属了各个振动峰位和增强峰位;研究了阿莫西林对照品溶液与DNA相互作用的荧光光谱和表面增强拉曼光谱.结果表明:阿莫西林胶囊与阿莫西林对照品的NRS及SERS图谱基本一致,说明胶囊中的辅料对阿莫西林的检测几乎没有影...     

喇曼感生克尔效应光谱的琼斯矩阵分析

介绍喇曼感生克尔效应光谱(RIKES)的琼斯(Jones)矩阵分析方法.探测光束的传输强度不仅由所经过的每一个光学器件的琼斯矩阵所决定,而且还受到强的泵波在非线性介质样品中感生依赖于强度的二向色性和双折射(克尔效应)对琼斯矩阵的影响.同时计及样品和光学器件由强泵波作用下感生应力和其他外部产生的线双折射对喇曼感生克尔效应光谱观察的不利影响,导出测量系统的功率传输函数的完整表达式和喇曼感生克尔效应光谱的实现观察条件,最后简述以甲笨(C_7H_8)液体为试样的喇曼感生克尔效应光谱实验结果分析.     

Non‐invasive depth profiling by space and time‐resolved Raman spectroscopy

Time‐resolved Raman spectroscopy, spatially offset Raman spectroscopy and time‐resolved spatially offset Raman spectroscopy (TR‐SORS) have proven their capability for the non‐invasive profiling of deep layers of a sample. Recent studies have indicated that TR‐SORS exhibits an enhanced selectivity toward the deep layers of a sample. However, the enhanced depth profiling efficiency of TR‐SORS, in comparison with time‐resolved Raman spectroscopy and spatially offset Raman spectroscopy, is yet to be assessed and explained in accordance to the synergistic effects of spatial and temporal resolutions. This study provides a critical investigation of the depth profiling efficiency of the three deep Raman techniques. The study compares the efficiency of the various deep Raman spectroscopy techniques for the stand‐off detection of explosive precursors hidden in highly fluorescing packaging. The study explains for the first time the synergistic effects of spatial and temporal resolutions in the deep Raman techniques and their impact on the acquired spectral data. Copyright © 2013 John Wiley & Sons, Ltd.     

Applications of Raman spectroscopy in herbal medicine

Raman spectroscopic techniques are a group of chemical fingerprint detection methods based on molecular vibrational spectroscopy. They are compatible with aqueous solutions and are time saving, nondestructive, and highly informative. With complementary and alternative medicine (CAM) becoming increasingly popular, more people are consuming natural herbal medicines. Thus, chemical fingerprints of herbal medicines are investigated to determine the content of these products. In this study, I review the different types of Raman spectroscopic techniques used in fingerprinting herbal medicines, including dispersive Raman spectroscopy, resonance Raman spectroscopy, Fourier transform (FT)–Raman spectroscopy, surface-enhanced Raman scattering (SERS) spectroscopy, and confocal/microscopic Raman spectroscopy. Lab-grade Raman spectroscopy instruments help detect the chemical components of herbal medicines effectively and accurately without the need for complicated separation and extraction procedures. In addition, portable Raman spectroscopy instruments could be used to monitor the health and safety compliance of herbal products in the consumer market.     

Recent advances in linear and nonlinear Raman spectroscopy. Part VII

The aim of this paper is to provide an overview of advances in the field of Raman spectroscopy as reflected in articles published each year in the Journal of Raman Spectroscopy as well as in trends across related journals publishing in this research area. The context for this review is derived from statistical data on article counts obtained from Thomson Reuters ISI Web of Knowledge by year and by subfield of Raman spectroscopy. Additional information is gleaned from presentations featuring Raman spectroscopy presented at the International Conference on Advanced Vibrational Spectroscopy in Kobe Japan in August 2013 and at SCIX 2013 sponsored by the Federation of Analytical Chemistry and Spectroscopy Societies in Milwaukee, Wisconsin, USA, October 2013. Papers published in the Journal of Raman Spectroscopy in 2012 are highlighted in this review and reflect topics and advances at the frontier of Raman spectroscopy, a field that is expanding rapidly as a sensitive photonic probe of matter at the molecular level in an ever widening sphere of novel applications. Copyright © 2013 John Wiley & Sons, Ltd.     

Recent advances in linear and non‐linear Raman spectroscopy. Part III

Following the first two reviews on recent advances in linear and non‐linear Raman spectroscopy, the present review summarises papers mainly published in the Journal of Raman Spectroscopy during 2008. This again serves to give a brief overview of recent advances in this research field and to provide readers of this journal a quick introduction to the various sub‐fields of Raman spectroscopy. It also reflects the current research interests and trends in the Raman community. Copyright © 2009 John Wiley & Sons, Ltd.     

Measurement and calculation of the Q‐branch spectrum of nitrogen using inverse Raman spectroscopy and cw Raman‐induced polarization spectroscopy

The techniques of inverse Raman spectroscopy, Raman‐induced polarization spectroscopy (RIPS), and optical heterodyne RIPS (OHD‐RIPS) are compared by probing the Q‐branch of the nitrogen molecule. The signal is measured employing either a photomultiplier tube (low background level–RIPS) or a photodetector (high background level–IRS and OHD‐RIPS). The measurements are performed using atmospheric mixtures of N₂ Ar with concentrations varying from 0 to 79% N₂. This strategy permits estimation of detection limits using the different techniques. Pump and probe energy levels are varied independently to study signal dependence on laser irradiance. A theoretical treatment is presented on the basis of the Raman susceptibility equations, which permits the calculation of spectra for all three techniques. Calculated Q‐branch spectra are compared with the measured spectra for the interactions of a linearly polarized probe beam with a linearly or circularly polarized pump beam. The polarizer angle in the detection path for OHD‐RIPS has a dramatic effect on the shape of the spectrum. The calculated and experimental OHD‐RIPS spectra are in good agreement over the entire range of investigated polarizer angles. Detection limits using these techniques are analyzed to suggest their applicability for measuring other species of importance in combustion and plasma systems. Copyright © 2007 John Wiley & Sons, Ltd.     

Recent advances in linear and non‐linear Raman spectroscopy. Part IX

This annual review is published to provide an overview of advances in the field of Raman spectroscopy as reflected in papers published each year in the Journal of Raman Spectroscopy (JRS) as well as in trends across related journals that have published papers in the broad field of Raman spectroscopy. The content is obtained from statistical data on article counts obtained from Thomson Reuters ISI Web of Science Core Collection by year and by subfield of Raman spectroscopy. Additional information is gleaned from presentations at the VIII International Conference on Advanced Vibrational Spectroscopy (ICAVS‐8) in Vienna, Austria in July 2015 and those featuring Raman scattering at SCIX 2015 organized by the Federation of Analytical Chemistry and Spectroscopy Societies (FACSS) in Providence, Rhode Island, USA, in September/October 2015. Coverage is also provided for topics from the conference ECONOS 2015 held in April in Leuven, Belgium. Finally, papers published in JRS in 2014 are highlighted and arranged by topics at the frontier of Raman spectroscopy. Taken from these various viewpoints, it is clear that Raman spectroscopy continues to be a rapidly expanding field that provides sensitive photonic information of matter at the molecular level in an ever‐widening arena of novel applications. Copyright © 2015 John Wiley & Sons, Ltd.     

Recent advances in linear and nonlinear Raman spectroscopy. Part IV

The purpose of the review is to provide a concise overview of recent advances in the broadly defined field of Raman spectroscopy as reflected in part by the many articles published each year in the Journal of Raman Spectroscopy (JRS) as well as in trends across all related journals publishing in this research area. Context for the review is provided by considering statistical data on citations for the Thompson Reuters ISI Web of Science by year and by subfield of Raman spectroscopy. Additional statistics of number of papers and posters presented by category at the XXII International Conference on Raman Spectroscopy (ICORS 2010) is also provided. Papers published in JRS in 2009, as reviewed here, reflect trends at the cutting edge of Raman spectroscopy which is expanding rapidly as a sensitive photonic probe of matter at the molecular level with an ever widening sphere of novel applications. Copyright © 2010 John Wiley & Sons, Ltd.     

Recent Advances in linear and nonlinear Raman spectroscopy I

Raman spectroscopy has advanced considerably in the last several years due to rapid developments in instrumentation and the availability of theoretical methods for accurate calculation of Raman spectra, thus enormously facilitating the interpretation of Raman data. This review is restricted to cover papers mainly published in the Journal of Raman Spectroscopy, which serve to give a fast overview of recent advances in this research field as well as to provide readers of this journal a quick introduction to the various subfields of Raman spectroscopy. It also reflects the current research interests of the Raman community. Similar reviews of highly active areas of Raman spectroscopy will appear in future issues of this journal. Copyright © 2007 John Wiley & Sons, Ltd.     

Recent advances in linear and nonlinear Raman spectroscopy. Part V

The purpose of the review is to provide a concise overview of recent advances in the broadly defined field of Raman spectroscopy as reflected in part by the many articles published each year in JRS as well as in trends across all related journals publishing in this research area. Context for this review is derived from statistical data on article counts obtained from Thomson Reuters ISI Web of Knowledge by year and by subfield of Raman spectroscopy. Additional information is gleaned from presentations featuring Raman spectroscopy presented at the meetings of the Federation of Analytical Chemistry and Spectroscopy Societies 2011 and the Sixth International Conference on Advanced Vibrational Spectroscopy 2011. Papers published in JRS in 2010, as reviewed here, reflect trends at the cutting edge of Raman spectroscopy, which is expanding rapidly as a sensitive photonic probe of matter at the molecular level with an ever‐widening sphere of novel applications. Copyright © 2011 John Wiley & Sons, Ltd.