Atomic emission spectrometry applications

Multielement Analysis by Atomic Emission Spectrometry. Applications of a Simultaneous Multielement Wavelength Profiling Facility for Diagnosis of Stray Light and Spectral Line Interference Effects, Third Annual Meeting of the Federation of Analytical Chemistry and Spectroscopy Societies, Philadelphia, PA, November 15, 1976, paper no. 79. 

Note that the interfacing of LC techniques with MS puts significant constraints on the solvents that can be used i.e., they must be volatile, with a low salt concentration, for MS compatibility. Narrow-bore columns, which use much smaller amounts of salt and organic modifier, appear to have potential for facilitating IEC-MS applications.40 Despite the excellent sensitivity of MS detection for most elements, however, there are cases where matrix effects can interfere. In this situation, combination of IEC with atomic emission spectrometry (AES) or atomic absorption spectrometry (AAS) may be preferable, and can also provide better precision.21 32 4142 Other types of... 

Applications Atomic emission spectrometry has been used for polymer/additive analysis in various forms, such as flame emission spectrometry (Section 8.3.2.1), spark source spectrometry (Section 8.3.2.2), GD-AES (Section 8.3.2.3), ICP-AES (Section 8.3.2.4), MIP-AES (Section 8.3.2.6) and LIBS. Only ICP-AES applications are significant. In hyphenated form, the use of element-specific detectors in GC-AED (Section 4.2) and PyGC-AED deserves mentioning. 

Instrumentation. Flame Characteristics. Flame Processes. Emission Spectra. Quantitative Measurements and Interferences. Applications of Flame Photometry and Flame Atomic Emission Spectrometry. 

Applications of Flame Photometry and Flame Atomic Emission Spectrometry... 

Owing to their superior fluorescent yield, heavy elements ordinarily yield considerably more intense XRF bands than the light elements. This feature can be exploited to determine the concentration of inorganic species in a sample, or the concentration of a compound that contains a heavy element in some matrix. Many potential XRF applications have never been developed owing to the rise of atomic spectroscopic methods, particularly inductively coupled plasma atomic emission spectrometry [74]. Nevertheless, under the right set of circumstances, XRF analysis can be profitably employed. 

Flame AAS (often abbreviated FAAS) was until recently the most widely used method for trace metal analysis. However, it has now largely been superseded by inductively coupled plasma atomic emission spectrometry (see Chapter 4). It is particularly applicable where the sample is in solution or readily solubilized. It is very simple to use and, as we shall see, remarkably free from interferences. Its growth in popularity has been so rapid that on two occasions, the mid-1960s and the early 1970s, the growth in sales of atomic absorption instruments has exceeded that necessary to ensure that the whole face of the globe would be covered by atomic absorption instruments before the end of the century. 

Further designs of ion sources applied in plasma spectroscopy such as electrodeless microwave induced plasmas (MIPs) operating in a noble gas atmosphere at low power (mostly below 200 W) or capacitively coupled microwave plasma using Ar, He or N2 the as plasma gas (at 400-800 W) were described in detail by Broekaert.33 Microwave plasmas produced by a magnetron are operated at 1-5 GHz. Their special application fields for selected elements and/or element species are based (due to the low power applied) in atomic emission spectrometry.33... 

J. M. Costa-Fernandez, F. Lunzer, R. Pereiro, N. Bordel and A. Sanz-Medel, Direct coupling of high-performance liquid chromatography to microwave-induced plasma atomic emission spectrometry via volatile-species generation and its application to mercury and arsenic speciation, J. Anal. At. Spectrom., 10, 1995, 1019-1025. 

M. Zougagh, P. C. Rudner, A. Garcia-de-Torres and J. M. Cano-Pavon, Application of Doehlert matrix and factorial designs in the optimisation of experimental variables associated with the on-line preconcentration and determination of zinc by flow injection inductively coupled plasma atomic emission spectrometry, J. Anal. At. Spectrom., 15(12), 2000, 1589-1594. 

Until now, little attention has been given to the analysis of ancient copper alloys with LA-ICP-MS. This type of material is usually analyzed with fast or instrumental neutron activation analysis (FNAA or INAA), particle induced X-ray emission (PIXE), X-ray fluorescence (XRF), inductively coupled plasma-atomic emission spectrometry or inductively coupled plasma-atomic absorption spectrometry (ICP-AES or ICP-AAS). Some of these techniques are destructive and involve extensive sample preparation, some measure only surface compositions, and some require access to a cyclotron or a reactor. LA-ICP-MS is riot affected by any of these inconveniences. We propose here an analytical protocol for copper alloys using LA-ICP-MS and present its application to the study of Matisse bronze sculptures. 

The application of inductively coupled plasma atomic emission spectrometry and graphite furnace atomic absorption spectrometry to the determination of cadmium (and molybdenum) in soils has been discussed by Baucells et al. [53]. Baucells et al. chose the 228.802 nm cadmium line because it is well resolved from the 228.763 nm iron line with the spectrometer used in this work. Background measurements could only be carried out at +0.05 nm. These workers obtained good agreement between cadmium values obtained by direct graphite furnace atomic absorption spectrometry and inductively coupled plasma atomic emission spectrometry. Chelation extraction procedures that require extensive sample handling are avoided. 

By far the most common type of plasma used for speciation analysis is the inductively coupled plasma (ICP) with mass spectrometry (MS) or atomic emission spectrometry (AES) detection. The performance of the ICP-MS system has been well documented since its development in the early 1980s by the Gray and Houk research groups [14,15], and it is now used for a wide variety of applications such as environmental, clinical, geological, food, and industrial analysis. 

For instance, those elements present at relatively high concentration levels in milk are usually determined by FAAS or flame atomic emission spectrometry (FAES). On the other hand, if better LoDs are needed (e.g., ng g-1), the technique of choice would be ET-AAS. For multielemental analysis plasma-based techniques are recommended, such as AES for major elements and trace elements, or, as described below, mass spectrometry (MS) for major, trace, and ultratrace elements. The most relevant applications of these atomic techniques for elemental analysis in milk samples are summarized in Table 13.7. 

APPLICATIONS OF FLAME PHOTOMETRY . /lND FLAME - ATOMIC EMISSION SPECTROMETRY... 

As noted earlier, USNs have been employed for sample insertion into atomic spectrometers suoh as flame atomio absorption spectrometry (FAAS) [9,10], electrothermal atomic absorption speotrometry (ETAAS) [11], atomic fluorescence spectrometry (AFS) [12,13], induotively ooupled plasma-atomic emission spectrometry (ICP-AES) [14,15], inductively coupled plasma-mass spectrometry (ICP-MS) [16,17] and microwave induced plasma-atomic emission spectrometry (MIP-AES) [18,19]. Most of the applications of ultrasonic nebulization (USNn) involve plasma-based detectors, the high sensitivity, selectivity, precision, resolution and throughput have fostered their implementation in routine laboratories despite their high cost [4]. 

Other authors in this volume have addressed the importance of trace and ultratrace quantities of various substances as they relate to nutritional, environmental, and occupational aspects of human health. This chapter will focus more on the development and application of a specific analytical procedure, based on inductively coupled plasma-atomic emission spectrometry (ICP-AES), for the rapid, simultaneous determination of a number of trace elements in human urine. 

Spreadsheet Summary In Chapter 4 of Applications of Microsoft Excel in Analytical Chemistiy, a multiple standard additions procedure is illustrated. The determination of strontium in sea water with inductively coupled plasma atomic emission spectrometry is used as an example. The worksheet is prepared, and the standard additions plot is made. The unknown Sr concentration and its standard deviation are obtained. 

Karanassios V., Abdullah M. and Horlick G. (1990) The application of chemical modification in direct sample insertion-inductively coupled plasma-atomic emission spectrometry, Spectrochim Acta, Part B 45 119—... 

As shown in the discussion above, there are a multiplicity of desirable and undesirable features of OID s that impact their general application as detectors in analytical atomic emission spectrometry. It is therefore appropriate to compare, in a critical and objective sense, the experimental figures of merit of these devices vis-a-vis the classical polychromator photomultiplier approach. These comparisons should be performed virtually on a continuing basis because of advances in performances, not only of the array detectors themselves but also in the associated spectroscopic excitation sources. An evaluation of the overall performance figures of merit of OID s when they are employed in conjunction with induction-coupled plasma excitation is of particular current interest because of the popularity that this source is attaining for the simultaneous determination of the elements at all concentration levels. In this paper we present such an evaluation for self-scanned, photodiode array detectors... 

Despite the absence of any known biological roles for strontium, analysis of trace amounts of the alkali earth metal in many environmental and industrial samples and, especially, in radioactive waste is of critical importance. Techniques applicable for analyzing strontium in environmental or biological material are atomic absorption spectrometry (AAS), inductively coupled plasma atomic emission spectrometry (ICP-AES), direct-current plasma echelle spectrometry, neutron activation analysis and X-ray fluorescence. For most applications, the first two mentioned methods are of interest because, in general, they allow... 

Other varied AAS applications reports including critical and comparative studies are by Ybanez et al. (1992) (Arsenic in seafood products by hydride generation atomic absorption spectrometry and a critical comparative study with platform furnace Zeeman-effect atomic absorption spectrometry and inductively coupled plasma atomic emission spectrometry) Campos et al. 

Applications considerations are included in many chapters in Vol 3 of Dean and Rains (1975) devoted to the determination of specific elements, and in various natural and manufactured materials. Methods for analytical atomic spectroscopy, 8th edition (ASTM 1987) contains a wealth of information based on evaluation and approval deliberations by the respected ASTM, including various computation practices, general laboratory practices, practices and methods for analysis of metallurgical and inorganic materials by spectrochemical techniques including flame atomic emission. Dawson et al. (1993) have published a tutorial review on background and background correction in analytical atomic emission spectrometry. 

Treatment of ICPAES from different perspectives and to varying degrees of comprehensiveness appears in a number of chapters in volumes not solely dedicated to ICP-AES, but treating spectrometry and analysis in general. An early excellent chapter on ICP-AES is by Tschopel (1979) on plasma excitation in spectrochemical analysis, in Wilson and Wilson s Comprehensive Analytical Chemistry. A very brief historical introduction to ICP-AES, basic principles and considerations of absorption and emission lines, and applications to food analysis is in a book on modern food analysis (Ihnat (1984), and Van Loon (1985), in his practical analyst-oriented book on selected methods of trace analysis biological and environmental samples includes a chapter (pp. 19-52) on techniques and instrumentation including ICPAES. Moore (1989) (Introduction to Inductively Coupled Plasma Atomic Emission Spectrometry) provides... 

S. D. Hartenstein, G. D. Christian, and J. Riiiidka, Applications of an On-Line Preconcentrating Flow Injection Analysis System for Inductively Coupled Plasma Atomic Emission Spectrometry. Can. J. Spectrosc., 30 (1986) 144. 

Modern atomic spectrometry methods can be considered as the most sensitive and specific analytical techniques which are available today for this wide field of application (Schramel et al., 1982). The most commonly used ones are atomic absorption and atomic emission spectrometry. The last mentioned technique is enjoying a renaissance due to the development of the different plasma excitation units, especially ICP, DCP and the different micro-wave induced plasmas (MIP) (Boumans 1978, 1979 Keirs and Vickers, 1977 Skogerboe and Coleman, 1976a, 1976b). 

This chapter deals with optical atomic, emission spectrometry (AES). Generally, the atomizers listed in Table 8-1 not only convert the component of samples to atoms or elementary ions but, in the process, excite a fraction of these species to higher electronic stales.. 4, the excited species rapidly relax back to lower states, ultraviolet and visible line spectra arise that are useful for qualitative ant quantitative elemental analysis. Plasma sources have become, the most important and most widely used sources for AES. These devices, including the popular inductively coupled plasma source, are discussedfirst in this chapter. Then, emission spectroscopy based on electric arc and electric spark atomization and excitation is described. Historically, arc and spark sources were quite important in emission spectrometry, and they still have important applications for the determination of some metallic elements. Finally several miscellaneous atomic emission source.s, including jlanies, glow discharges, and lasers are presented. 

FAAS is the oldest version of AAS. It works with liquid samples which after nebu-lization are mixed with acetylene and introduced in a flame atomizer burner with air-acetylene or N20-acetylene flame. A single measurement can be completed within 10 s. Theoretically the method is applicable to 60-70 elements and due to its low cost, selectivity and simple operation is preferred whenever the concentration of the determined elements is within its possibilities. The sensitivity of FAAS is of the same order of magnitude as of ICP-AES and for some elements even worse which in recent years has lead to the replacement of FAAS with the multielement ICP-AES. To increase the sensitivity of FAAS usually preconcentration procedures are applied before measurement. Otherwise FAAS permits direct measurements in the low mg/kg range of a number of metals in soils and sediments, six to ten elements in plants and in natural waters. It is sensitive enough for the direct determination of Al., Ba, Ca, Cu, Fe, K, Na, Mg, Mn and Zn in different environmental materials (alkaline metals are determined by flame atomic emission spectrometry). Due to the narrow dynamic range problems with the accuracy appear (e.g. Djingova et al., 1991) and very often dilutions are necessary which decreases relative sensitivity and increases the possibilities for errors. 

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