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An instrument combining laser-induced breakdown spectroscopy (LIBS) and Raman spectroscopy was developed for the in situ atomic and molecular composition analysis of minerals. The apparatus consist...

Laser-induced breakdown spectroscopy (LIBS) is capable of providing elemental analysis while Raman spectroscopy is powerful for molecular and structural characteristics of crystalline substances. T...

In this work, a compact laser induced breakdown spectroscopy (LIBS) instrument was developed based on a high energy lightweight laser source and an integrated control system, making the instrument ...

A newly designed and developed bench-top instrument is reported for laser-induced breakdown spectroscopy offering compact size and relatively low cost. A miniature laser was designed in the laboratory with a small volume and a light weight. The spectrometer was controlled using laboratory-written software. The instrument is suitable for the direct and rapid analysis of solid samples after simple pretreatment. Good stability and accuracy were achieved for quantitative analysis. The performance of the instrument was evaluated by qualitative and quantitative analyses of nickel ore for Mn, Al, Fe, Cr, Zn, Mg, Si, and Ca. The quantitative analysis showed linear calibration graphs and small relative standard deviations. The results show that the new instrument is suitable for elemental analysis.

Fiber optic-based biosensors with surface plasmon resonance (SPR) technology are advanced label-free optical biosensing methods. They have brought tremendous progress in the sensing of various chemical and biological species. This review summarizes four sensing configurations (prism, grating, waveguide, and fiber optic) with two ways, attenuated total reflection (ATR) and diffraction, to excite the surface plasmons. Meanwhile, the designs of different probes (U-bent, tapered, and other probes) are also described. Finally, four major types of biosensors, immunosensor, DNA biosensor, enzyme biosensor, and living cell biosensor, are discussed in detail for their sensing principles and applications. Future prospects of fiber optic-based SPR sensor technology are discussed.

Microplasma is a useful detector for analyzing the effluent of gas chromato-graphy due to its remarkable capacity for portability, high sensitivity, and excellent multielement selectivity. Compared to classical detectors, microplasma detectors have the advantages of small size, low cost, and low energy consumption in design and operation. We aim to provide an overview of microplasma detectors and show their applications in various chemical analyses. The operational characteristics and analytical performance of different microplasma detectors, such as capacitively coupled microplasma, glow discharge microplasma, and microhollow-cathode microplasma, are presented in detail to reveal the current status of microplasma detectors for gas chromatography. In addition, several approaches for the design of microplasma are discussed and the future trends in the development of microplasma detectors are highlighted at the end of this review. Various applications of microplasma detectors for gas chromatograph...

A novel adsorbent, chufa corm peels (CCP), is used for removing Cu(II), Cr(III), and Cr(VI) from aqueous solutions. The adsorption ability and characteristics of the CCP are thoroughly investigated. The adsorption capability for three heavy metal ions is in the order of Cu(II) > Cr(III) > Cr(VI). The morphology and elemental distribution on the biomass of CCP were evaluated by scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). Fourier-transform infrared spectroscopy (FTIR) analysis revealed that oxygen-containing functional groups, especially carboxylic and hydroxyl groups were responsible for chemical coordination between ionizable functional groups and metal ions. The adsorption features were evaluated based on the batch biosorption experiment. The results showed that the adsorption well meets the Freundlich adsorption isotherm models and pseudo-second-order kinetics model. In summary, this work demonstrated that CCP is an attractive, efficient, and low-cost adsorbent biomateri...

A modern trend in the development of laser-based analytical instruments is to integrate more functions in a single device, which could supply complementary information and improve the capability to identify different components. This review presents historical development of the combined analysis by laser-induced breakdown spectroscopy (LIBS) and Raman Spectroscopy, which briefly describes basic instrumental principles and technological aspects of the hyphenated technique, as well as the requirements in the design of interactive instruments, including laser systems, optical systems for laser beam delivery, emission collection devices, and spectrum measurement systems. Various configurations of the combined instrumentation have been designed and used depending on the different applications, such as pigment analysis in the cultural heritage field, detection of explosives, analysis of geological samples, and applications in future planetary missions. In addition, the feasibility, applicability, and...

Raman-based techniques have developed into excellent analytical tools in various research fields, primarily due to their noninvasive sampling capability, minimal sample preparation, and short analysis time. Major improvements in lasers, spectrometers, detectors, and holographic optical components have made Raman spectroscopy an effective tool for analyzing natural and synthetic materials. This article presents a short introduction to Raman spectroscopy and several recently related advances, including, Fourier transform (FT) Raman spectroscopy, micro-Raman spectroscopy, Raman sensing, and stand-off Raman spectroscopy techniques. Other topics discussed in this article are the importance of its combination with laser-induced breakdown spectroscopy (LIBS) and laser-induced fluorescence (LIF).

This review article describes some existing microplasma sources and their applications in analytical chemistry. These microplasmas mainly include direct current glow discharge (DC), microhollow-cathode discharge (MHCD) or microstructure electrode (MSE), dielectric barrier discharge (DBD), capacitively coupled microplasmas (CC mu Ps), miniature inductively coupled plasmas (mICPs), and microwave-induced plasmas (MIPs). The historical development and recent advances in these microplasma techniques are presented. Fundamental properties of the microplasmas, the unique features of the reduced size and volume, as well as the advantageous device structures for chemical analysis are discussed in detail, with the emphasis toward detection of gaseous samples. The analytical figures of merit obtained using these microplasmas as molecular/elemental-selective detectors for emission spectrometry and as ionization sources for mass spectrometry are also given in this review article.

In this short letter, we report a compact spectrophotometer consisting of a liquid core waveguide as the optical cell and a handheld charge coupled device spectrometer as the detector. This instrumentation features portability, ultrahigh sensitivity, simultaneous multicomponent detection, and minimal analyte solution. Its ultrahigh sensitivity permits the measurement of Cr(III) without coloration with any reagents. Therefore, a simple, fast, cost-effective, and green analytical method was developed for the ultrasensitive and simultaneous speciation analysis of Cr(III) and Cr(VI) in water samples, with the limits of detection down to the ppb level.

Due to the great potentials in clinical diagnosis, disease state monitoring, and environmental exposure assessment, the breath test is becoming one of the most desirable noninvasive procedures for clinical diagnostics. This article reviews the technical aspects of breath analysis including sample collection, analyte preconcentration, vapor desorption, and various measurement techniques, as well as some recent developments in the field. Because the exhaled breath is affected by the composition of ambient air, the elimination of background influence on the analyte detection is also discussed. Both advantages and major obstacles of breath analysis techniques in clinical practice are presented and summarized. This article not subject to United States Copyright law.