Showing papers in "Applied Spectroscopy Reviews in 2008"
TL;DR: In this article, a review of the recent advances on FTIR spectroscopy in areas related to natural tissues and cell biology is presented, which summarizes some of the most widely used peak frequencies and their assignments.
Abstract: This article reviews some of the recent advances on FTIR spectroscopy in areas related to natural tissues and cell biology. It is the second review publication resulting from a detailed study on the applications of spectroscopic methods in biological studies and summarizes some of the most widely used peak frequencies and their assignments. The aim of these studies is to prepare a database of molecular fingerprints, which will help researchers in defining the chemical structure of the biological tissues introducing most of the important peaks present in the natural tissues. In spite of applying different methods, there seems to be a considerable similarity in defining the peaks of identical areas of the FTIR spectra. As a result, it is believed that preparing a unique collection of the frequencies encountered in FTIR spectroscopic studies can lead to significant improvements both in the quantity and quality of research and their outcomes. This article is the first review of its kind that provides...
1,253 citations
TL;DR: In this paper, an overview of modern techniques of sample preparation for food analysis employing atomic and inorganic mass spectrometric techniques, such as flame atomic absorption, chemical vapor generation atomic absorption and atomic fluorescence spectrometry, graphite furnace atomic absorption spectrometer, inductively coupled plasma optical emission spectrometrization, and induction coupled plasma mass spectroscopy, is presented.
Abstract: The present article gives an overview of recent publications and modern techniques of sample preparation for food analysis employing atomic and inorganic mass spectrometric techniques, such as flame atomic absorption spectrometry, chemical vapor generation atomic absorption and atomic fluorescence spectrometry, graphite furnace atomic absorption spectrometry, inductively coupled plasma optical emission spectrometry, and inductively coupled plasma mass spectrometry. Among the most frequently applied sample preparation techniques for food analysis are dry ashing, usually with the addition of an ashing aid, and acid digestion, preferably with the assistance of microwave energy. Slurry preparation, particularly with the assistance of ultrasound, is increasingly used to reduce acid consumption and sample preparation time. Direct analysis of solid samples is gaining importance in the field of food analysis as it offers the highest sensitivity, avoids the use of acids and other aggressive reagents, make...
205 citations
TL;DR: In this paper, the development of new sorbents and their application in preconcentration methods for determination of trace elements is a subject of great interest, and several analytical methods involving the preparation and use of new solid phase materials are discussed.
Abstract: The development of new sorbents and their application in preconcentration methods for determination of trace elements is a subject of great interest. This review summarizes and discusses several analytical methods involving the preparation and use of new solid‐phase materials. The performance and general properties of sorbents such as carbon nanotubes, imprinted ions, biosorbents, nanoparticles, and fullerene are discussed in detail. The perspective and future trends in the use of these materials are also considered.
150 citations
TL;DR: In this article, a review of high-and low-resolution solid-state nuclear magnetic resonance (SSNMR) applications to the study of pharmaceuticals is presented, where the most important aspects treated concern structural, dynamic, and morphological properties, and, in particular, identification, characterization, and quantitation of polymorphs and related forms, conformational and crystalline packing behavior, amorphous phase properties and stability, effects of drug processing, molecular motions, API•excipient and excipient•excipients chemical and physical interactions, and phase mixing in hetero...
Abstract: High‐and low‐resolution solid‐state nuclear magnetic resonance (SSNMR) applications to the study of pharmaceuticals are reviewed. Examples are shown involving the use of mono‐and bidimensional SSNMR techniques based on different nuclear interactions and the measurement of several nuclear parameters, such as chemical shifts, line widths, and relaxation times (T1, T2, T1ρ). The systems investigated include pure active pharmaceutical ingredients (APIs), substances used as drug excipients, and solid dispersions formed by APIs and excipients, up to final drug formulations. The most important aspects treated concern structural, dynamic, and morphological properties, and, in particular, identification, characterization, and quantitation of polymorphs and related forms, conformational and crystalline packing behavior, amorphous phase properties and stability, effects of drug processing, molecular motions, API‐excipient and excipient‐excipient chemical and physical interactions, and phase mixing in hetero...
141 citations
TL;DR: The characterization of a variety of organic/inorganic multicomponent materials (OIMM) through solid-state NMR (SSNMR) spectroscopy is reviewed in this paper.
Abstract: The characterization of a variety of organic/inorganic multicomponent materials (OIMM) through solid-state NMR (SSNMR) spectroscopy will be reviewed. Many examples of applications to OIMM will be described, based on the observation of different nuclei and the use of various SSNMR methods, such as 1D and 2D techniques, measurements on relaxation and spin diffusion processes. OIMM are a very general category of systems differing, for example, by chemical nature and relative amount of organic and inorganic components, shape and size of the domains, and type of organic-inorganic interface. Some of the most investigated classes of OIMM are organically modified silicates, polymer/clay composites, polymer/inorganic filler systems, polymer electrolytes, stationary chromatographic phases, zeolites, and mesoporous silicas including small organic molecules. The aspects most efficiently investigated by SSNMR and discussed in this review include physical and/or chemical interactions occurring at the organic-i...
80 citations
TL;DR: In this article, the authors provide a valuable source of information on the technological advances in near infrared absorption spectrometry area and its industrial applications, especially on the alimentary technology and environmental applications over biofuels.
Abstract: This review provides a valuable source of information on the technological advances in near infrared absorption spectrometry area and its industrial applications, especially on the alimentary technology and environmental applications over biofuels.
54 citations
TL;DR: In this paper, the spectral properties of the saccharides and related materials were investigated and applied to the monitoring of the enzyme reaction and the sugar metabolic processes, which are the main materials in food processing, and the results suggest that infrared spectroscopy could be very effective for evaluating foodstuff production and the tasting of the processed foods.
Abstract: Integrated investigations on infrared spectroscopic characteristics of metabolites and on applications of infrared spectroscopy to foodstuff production, food processing, and tasting are described. As the important metabolites, saccharides, which play very important roles in various functions, located in the central position of the metabolic pathways, were selected, and the spectral features of the saccharides and related materials are discussed. Additionally, the applications of spectral analysis to the monitoring of the enzyme reaction and the sugar metabolic processes, which are the main materials in food processing, are described. Furthermore, the studies on the spectroscopic measurements during the cultivation of agricultural products as foodstuffs and in the tasting as the final quality evaluation of foods are represented. These results suggest that infrared spectroscopy could be very effective for evaluating foodstuff production and the tasting of the processed foods and that the applied to...
53 citations
TL;DR: In this paper, a review of TLS detection in liquid chromatography, ion chromatography and capillary electrophoresis is presented, focusing on the analysis of real samples and the performances of various detection schemes in combination with chromatographic techniques and FIA.
Abstract: Recent applications of thermal lens spectrometry in liquid chromatography (HPLC, ion chromatography), capillary electrophoresis, and flow injection analysis are reviewed. Possible effects of performing TLS measurements in flows are discussed initially for different TLS configurations. The emphasis is given to the analysis of real samples, and the performances of various detection schemes in combination with chromatographic techniques and FIA are discussed particularly in terms of sensitivity, sample throughput, and eventual interferences from complex matrices. Coaxial TLS detection with continuous wave excitation is most suitable for detection in HPLC, ion chromatography, and FIA using long‐path length cells, when large volume samples are available. On the other hand, transverse or crossed beam TLS was found most suitable for detection in CE where it provides low absolute LODs, which are lowered even further by thermal lens microscopy on microchips, where the capability of detecting a single mole...
50 citations
TL;DR: The topic of matrix-assisted laser desorption/ionization (MALDI) mass spectrometry has received much attention over the past several years and with the award of the Nobel Prize to Tanaka based on his landmark paper in 1988, has received even more recent attention as mentioned in this paper.
Abstract: The topic of matrix-assisted laser desorption/ionization (MALDI) mass spectrometry has received much attention over the past several years and with the award of the Nobel Prize to Tanaka based on his landmark paper in 1988, has received even more recent attention. This review focuses on the search for an ideal matrix and generally covers the period from the mid 1990's to the present. There have been a number of excellent and comprehensive reviews on MALDI ion formation and a brief summary of some of the most important conclusions is given here. With respect to the applications of MALDI, the present review focuses primarily on polymer analysis, although in this area too, excellent reviews have been published that include consideration of the MALDI method. Although we make some mention of other uses of MALDI (e.g., to proteins and peptides) and other biological applications, we emphasize the polymer uses in the present review.
47 citations
TL;DR: In this paper, the authors present and discuss the current state of the art in implementing miniaturised and automated sample treatments for environmental and biochemical assays via microfluidic systems exploiting the lab-on-valve (LOV) platform in hyphenation with syringe pump propelling devices as a front end to a plethora of spectroscopic detection schemes.
Abstract: One of the current needs within the analytical spectrometric community is the development of straightforward and cost‐effective, yet rugged, sample processing procedures aimed at precluding both spectroscopic and nonspectroscopic matrix interferences while fostering concomitant sample enrichment. Illustrated via selected representative examples, this review presents and discusses the current state of the art in implementing miniaturised and automated sample treatments for environmental and biochemical assays via microfluidic systems exploiting the lab‐on‐valve (LOV) platform in hyphenation with syringe pump propelling devices as a front end to a plethora of spectroscopic detection schemes including ultraviolet‐visible (UV‐Vis) spectrometry, spectrofluorimetry, chemiluminescence, atomic absorption spectrometry (AAS), atomic flourescence spectrometry (AFS), and inductively coupled plasma‐atomic emission spectrometry/mass spectrometry (ICP‐AES/MS). In contrast to lab‐on‐a‐chip units, the versatile c...
30 citations
TL;DR: The multipleangle incidence resolution spectrometry (MAIR) is a potentially useful spectroscopic technique for quantitative analysis of molecular orientation in thin films deposited on a solid substrate as mentioned in this paper.
Abstract: Multiple‐angle incidence resolution spectrometry (MAIRS) is a potentially useful spectroscopic technique for quantitative analysis of molecular orientation in thin films deposited on a solid substrate Although the technique is based on a unique measurement concept and theory, it can easily be equipped on a commercial FT‐IR and the operation is user friendly In this review, representative application studies of MAIRS are summarized as well as a recent new theoretical approach to get over a conventional experimental limitation that a high‐refractive‐index substrate is necessary for quantitatively reliable MAIRS analysis
TL;DR: In this paper, a review of applications of near-field laser ablation for solid sample introduction are explored, and a descriptive overview of the near field region is given, and methods of generating a near field regions and several processes for tip manufacture are described.
Abstract: Traditional laser ablation is a well‐known method of solid sampling for surface characterization, but the resolution of the technique has been limited by the diameter of the incident laser beam and is typically on the order of 100–200 µm. Unfortunately, this microscale resolution can be too low to characterize isolated surface features that have submicron dimensions. Near‐field laser ablation is an emerging analytical tool for nanoscale, high‐resolution surface analysis. In this review, applications of near‐field laser ablation for solid sample introduction are explored. Also, a descriptive overview of the near‐field region is given, and methods of generating a near‐field region and several processes for tip manufacture are described.
TL;DR: In this article, the authors review the theoretical models of single chain stretching, the latest progress in force extension measurements by static and dynamic AFM modes for polymeric chains, and modified quantum mechanics principles to account for entropic and enthalpic contributions to stretching in the high-force Hookean regime.
Abstract: In recent years, remarkable advances in research of the mechanical and structural properties of single polymer chains have been achieved thanks to atomic force microscope (AFM)‐based single molecule force spectroscopy (SMFS). This technique offers great possibilities to investigate the mechanical properties of a single polymer chain by static/dynamic force‐extension measurements at the mesoscale level. Data are analyzed with the help of appropriate theoretical models, such as statistical mechanics models for freely jointed chains (FJC) or worm‐like chains (WLC), which can well describe the moderate entropy‐controlled stretch of most polymers, and with semiclassical models, which are being modified using quantum mechanics principles to account for entropic and enthalpic contributions to stretching in the high‐force Hookean regime. In this article we review the theoretical models of single chain stretching, the latest progress in force‐extension measurements by static and dynamic AFM modes for poly...
TL;DR: In this article, the trade-off between time resolution and the level of detail of information were discussed, and the tradeoff between the high time resolution of single photon counting devices with the large field of view and spectral resolution allowed by two-dimensional detectors.
Abstract: Techniques based on fluorescence have played a variety of roles in chemistry, physics, spectroscopy, medicine, nanotechnology, and biotechnology due to their high selectivity, sensitivity, simplicity, and fastness in spectroscopic and imaging measurements. While detecting fluorescence from individual molecules by fluorescence‐based techniques, poor signal, limited lifespan of fluorophores, trade‐off between time resolution, and the level of detail of information were few major concerns. Ultrasensitive detectors permit the combination of the high time resolution of single photon counting devices with the large field of view and spectral resolution allowed by two‐dimensional detectors. Photobleaching and on‐off blinking of fluorophores can be improved dramatically by chemical modifications or changing the reagents. New ways of controlling local fields such as optic, electric, magnetic, chemical, or biochemical environments take advantage of the noninvasiveness and high temporal and spatial resoluti...