Laser-based standoff detection of explosives: a critical review

A review of standoff detection technologies for explosives has been made. The review is focused on trace detection methods (methods aiming to detect traces from handling explosives or the vapours surrounding an explosive charge due to the vapour pressure of the explosive) rather than bulk detection methods (methods aiming to detect the bulk explosive charge). The requirements for standoff detection technologies are discussed. The technologies discussed are mostly laser-based trace detection technologies, such as laser-induced-breakdown spectroscopy, Raman spectroscopy, laser-induced-fluorescence spectroscopy and IR spectroscopy but the bulk detection technologies millimetre wave imaging and terahertz spectroscopy are also discussed as a complement to the laser-based methods. The review includes novel techniques, not yet tested in realistic environments, more mature technologies which have been tested outdoors in realistic environments as well as the most mature millimetre wave imaging technique. Figure Standoff detection and identification is one of the most wanted capabilities     

A DNA hybridization assay using nanogold-streptavidin,electro-microchip and silver enhancement to analyze impedance signals

This paper reports a novel DNA hybridization detection method using gold-streptavidin conjugates as a reporter, the silver enhancement reaction to magnify the detection signal, a commercial LCR meter to detect the hybridization signal. The relationships between sample concentration and detection signal are discussed and the detection limit for the DNA sample is 0.825 ng/mL. Moreover, the probe specific tests are discussed for different species of bacteria, for same species but different strains, and for same genus but different species.     

毛细管电泳安培型电化学检测法

本文评述了近年来安培型电化学检测法在毛细管电泳中的发展概况，归纳了二种检测方式及其装置的结构特点。阐述了金属电极、液膜电极和修饰电极等在电化学检测应用研究中的作用以及此方法在微区分析、活体分析中的重要意义，并展望了其发展前景。     

单碱基多样性的非测序检测

单碱基多样性（SNP）是最常见的基因突变形式之一,经研究证明与很多疾病相关。虽然测序是检测SNP的重要方法,但其需要检测仪器,且检测时间较长,限制了其临床应用。本文综述了SNP的常见非测序分析方法。首先讨论了检测的热力学问题,并归纳了主要的检测策略：基于杂交的检测,基于链取代反应的检测和酶介导的检测。在三维均相检测方法中,主要介绍了不同信号开关策略,如荧光开关、酶识别开关和场效应开关。三维原位检测不仅能检测SNP,还能提供其细胞定位信息,在细胞异质性较高时更具优势。二维界面检测的识别反应速率和杂交效率受到一定影响,但界面检测能进一步减小干扰,亦便于实现高通量检测。以DNA正四面体探针界面为代表的改良界面具有优良的灵敏度和特异性。同时本文亦讨论了现有方法的局限性,并对SNP非测序检测研究进行展望。     

Qualitative and quantitative analysis in quality control of traditional Chinese medicines

Separation techniques with high efficiency and sensitive detection have been widely used for quality control of traditional Chinese medicines (TCMs). High-performance liquid chromatography, gas chromatography, and capillary electrophoresis are commonly used to separate various components in TCMs. Ultraviolet detection, fluorescence detection, evaporative light-scattering detection, mass spectrometry and nuclear magnetic resonance can be applied to separation techniques for qualitative and quantitative analysis of TCMs. The development of quality control for TCMs based on quantitative and qualitative analysis from 2000 to 2007 are reviewed; the fingerprint technique is also discussed due to its broad application in the quality control of TCMs. Prospects for further research based on our primary results are also discussed.     

离子色谱中的安培检测方法及其应用

介绍了离子色谱中的安培检测方法(包括恒电位安培检测法、脉冲安培检测法和积分脉冲安培检测法)的原理和应用。脉冲安培检测法与高效阴离子交换色谱结合(HPAEC-PAD)是一种新的分析糖类化合物的方法;积分脉冲安培检测法与高效阴离子交换色谱结合(HPAEC-IPAD)是一种新的氨基酸分析方法。     

基因兴奋剂检测的现状与策略

本文综述了基因兴奋剂检测的现状和反基因兴奋剂的策略。归纳了可能被运动员滥用的基因兴奋剂,分析了由这些基因表达的促红细胞生成素(EPO)、人生长激素(hGH)等蛋白的检测进展,讨论了未来检测基因兴奋剂的可能策略。     

全内反射荧光成像技术及其在单分子检测中的研究进展

全内反射荧光显微镜技术是当今最灵敏的生物成像和检测方法之一,可以直接探测单个荧光分子。这种方法已成功地用于生命科学、化学、物理学等研究领域,获得了常规方法无法得到的重要信息。本文介绍了全内反射荧光显微镜的工作原理和实验技术,总结了近年来这种单分子检测方法在生命科学、化学等领域的重要应用,并对其发展前景进行了展望。     

Recent developments in detection for microfluidic systems

Microfluidic systems have become more and more important in the field of analytical chemistry. Detection methods on these microsystems are essential for the identification and quantification of chemical species that are being analyzed. This review concentrates on the latest developments of optical detection methods and mass spectrometry in conjunction with microfluidic systems. Electrochemical methods are discussed in another review in the same issue of this journal. Within the optical detection section, topics such as multiplexed detection and the use of waveguides are discussed. Within the discussion of mass spectrometry, the main focus is on electrospray emitters as interfaces between microsystem and spectrometer. Apart from optical detection and mass spectrometry, other techniques such as flame ionization and nuclear magnetic resonance are also mentioned.     

Resonance energy transfer methods of RNA detection

Quantitation of RNA is important in diagnostics, environmental science, and basic biomedical research. RNA is considered a signature for pathogen identification, and its expression profile is linked with disease pathogenesis, allowing for biomarker identification. RNA-based diagnostics is an emerging field of research. This expansion of interest in studying RNA has generated demand for its accurate and sensitive detection. Several methods have therefore been developed to detect RNA. Resonance energy transfer methods of RNA detection are highly promising in terms of simplicity and high sensitivity. In this review, we have focused on the latest developments in resonance energy transfer methods of RNA detection that utilize various probe designs. The probe designs discussed here are molecular beacons, quenched autoligation probes, and linear oligonucleotide probes. Resonance energy transfer methods based on both fluorescence and bioluminescence detection are discussed.     

Copolymer solutions as separation media for DNA capillary electrophoresis

Capillary electrophoresis techniques offer high plate numbers and are highly suited for the efficient separations of a wide variety of chemical components in diverse matrices. Because of the small capillary and detection cell dimensions, together with the minute volumes of samples to be injected, sensitive detection schemes based on different physicochemical principles are being developed. One logical approach to increased sensitivity in capillary electrophoresis detection has been the development of chemiluminescence-based detectors. The development of on-line ultrasensitive chemiluminescence detection (referred to the concentration detection limit of nM order of magnitude or mass detection limit of amol order of magnitude) in capillary electrophoresis system is reviewed. The applications and limitations of the current detection methodology are briefly considered and future prospects for the development are discussed.     

System Design and Emerging Hardware Technology for Ion Chromatography

This review provides an overview of advances in system design for ion chromatography (IC), focusing on the suppressed conductivity detection mode. In particular, advances in automated mobile-phase generation and suppressor technology based on different electrolytic concepts are addressed and novel detection approaches are discussed. Finally, advances in multi-dimensional IC and aspects of miniaturization, including capillary IC instrumentation and chip-based IC, are discussed.     

The sit image vidicon as a gas-phase fluorescence detector for gas chromatography

The feasibility of using an SIT Vidicon as a gas-phase fluorescence detector for gas chromatography is demonstrated. Operation of the SIT in both the “real time” and integration modes is discussed. The SIT system can subtract stored signals (spectra) from one another, so that background correction is possible and the spectral selectivity of vapor-phase fluorescence detection is enhanced. Gas-phase spectra and limits of detection for several polyaromatic hydrocarbons are given; the SIT gives limits of detection about a factor of five larger than those obtained with a photomultiplier (PM) tube (operated in a nonscanning mode).The relative merits of using the SIT system or a fast scanning (PM) system for measuring transient signals are discussed.     

Detection techniques in ion chromatography of inorganic ions

Trends in detection techniques for ion chromatographic separations of inorganic anions and cations are reviewed. Special attention is paid to conductivity, UV-vis absorbance, amperometric and potentiometric detection, mass spectrometry (MS) (including inductively coupled plasma MS and atmospheric pressure ionization MS) and post-separation reaction detection. The benefits and drawbacks of the different methods are discussed and examples are given for applications published within the last few years.     

LIF, LEI, RIMS etc. — New promising techniques in elemental micro- and trace analysis

Summary The application of laser spectroscopy in spectrochemistry requires excitation and detection schemes different from the estabolished optical spectrochemical methods. The most promising techniques developed in laser spectrochemistry are described and the analytical figures of merits are discussed. The very low absolute detection limits of the laser methods are required if trace elements have to be measured in microsamples.     

Detektion in der Hochdruck-Flüssigkeits-Chromatographie

Techniques, methods and problems of detection in highpressure liquid chromatography are discussed on the basis of recent publications. Experiences and findings from the field of gas-chromatographic detection are also dealt with.     

吖啶作为检测试剂脂肪醇和脂肪酸的间接光度高效液相色谱研究

以吖啶作为新型检测试剂,研究C_4～C_(12)脂肪醇、C_6～C_(16)脂肪酸的间接光度高效液相色谱,探讨影响色谱保留和产生间接光度响应的因素,从分离检测机理解释两类化合物色谱行为和检测响应的差别,提出新的分离测定脂肪醇和脂肪酸的间接光度高效液相色谱系统。     

Reinheitskontrolle von Wolfram mit der Funken-Massenspektrometrie

Summary Spark source mass spectrometry with photoplate detection has been used for the purity control of tungsten. The achievable detection limits and the accuracy are discussed. The results are compared with those of secondary ion mass spectrometry.     

Solid-surface room-temperature phosphorimetric detection of caffeine,theophylline and theobromine in liquid chromatography

Solid-surface room-temperature phosphorimetry (SSRTP) is proposed as an alternative detection technique for the liquid chromatographic determination of caffeine, theophylline and theobromine. The measurements are performed in a continuous mode with a two-nebulizer automated system for SSRTP detection. The analytical figures of merit obtained with the proposed detector are compared with those obtained by UV absorption detection. The SSRTP and UV chromatograms of spiked urine samples are compared, and the possibility of keeping the SSRTP substrates as permanent records of analyzed samples is discussed.