Inductively coupled plasma-atomic emission spectrometry—See

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 However, it has now largely been superseded by inductively coupled plasma atomic emission spectrometry (see Chapter 4).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. 

Inductively coupled plasma atomic emission spectrometry. See ICP-AES... 

Knowledge of the atomic spectra is also very important so as to be able to select interference-free analysis lines for a given element in a well-defined matrix at a certain concentration level. To do this, wavelength atlases or spectral cards for the different sources can be used, as they have been published for arcs and sparks, glow discharges and inductively coupled plasma atomic emission spectrometry (see earlier). In the case of ICP-OES, for example, an atlas with spectral scans around a large number of prominent analytical lines [329] is available, as well as tables with normalized intensities and critical concentrations for atomic emission spectrometers with different spectral bandwidths for a large number of these measured ICP line intensities, and also for intensities calculated from arc and spark tables [334]. The problem of the selection of interference-free lines in any case is much more complex than in AAS or AFS work. 

Internal standards are also used in trace metal analysis by inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS) techniques. An internal standard solution is added to ICP-MS and ICP-AES samples to correct for matrix effects, and the response to the internal standard serves as a correction factor for all other analytes (see also chapter 2). 

Many methods used for qualitative analysis are destmctive, that is, the sample is consumed during the analysis or must be chemically altered in order to be analyzed. The most sensitive and comprehensive elemental analysis methods for inorganic analysis are inductively coupled plasma atomic emission spectrometry (ICP-OES or ICP-AES), discussed in Chapter 7, and ICP-MS, discussed in Chapters 9 and 10. These techniques can identify almost all the elements in the periodic table, even when only trace amounts are present, but often require that the sample be in the form of a solution. If the sample is a rock or a piece of glass or a piece of biological tissue, the sample usually must be dissolved in some way to provide a solution for analysis. We will see how this is done later in the chapter. The analyst can determine accurately what elements are present, but information about the molecules in the sample is often lost in the sample preparation... 

Flame, flame atomic emission (see Topic E4) ICP-AES, Inductively coupled plasma-atomic emission spectrometry ICP-MS, Inductively coupled plasma-mass spectrometry. 

See also Atomic Emission Spectrometry Inductively Coupled Plasma. Atomic Mass Spectrometry Inductively Coupled Plasma. Liquid Chromatography Overview. Mass Spectrometry Eiectrospray. 

See also Activation Anaiysis Neutron Activation. Air Anaiysis Workpiace Air. Amperometry. Atomic Absorption Spectrometry Principies and Instrumentation. Atomic Emission Spectrometry Principles and Instrumentation Inductively Coupled Plasma. Atomic Mass Spectrometry Inductively Coupled Plasma. Capillary Electrophoresis Overview. Cement. Elemental... 

See also Activation Analysis Neutron Activation. Atomic Emission Spectrometry Inductively Coupled Plasma. Atomic Mass Spectrometry Inductively Coupled Plasma. Chemometrics and Statistics Expert Systems. Glasses. Microscopy Applications Forensic. Optical Spectroscopy Refractometry and Reflectometry. X-Ray Fluorescence and Emission Energy Dispersive X-Ray Fluorescence. 

See also Atomic Emission Spectrometry Inductively Coupled Plasma. Atomic Spectrometry Overview. 

Numerous methods have been pubUshed for the determination of trace amounts of tellurium (33—42). Instmmental analytical methods (qv) used to determine trace amounts of tellurium include atomic absorption spectrometry, flame, graphite furnace, and hydride generation inductively coupled argon plasma optical emission spectrometry inductively coupled plasma mass spectrometry neutron activation analysis and spectrophotometry (see Mass spectrometry Spectroscopy, optical). Other instmmental methods include polarography, potentiometry, emission spectroscopy, x-ray diffraction, and x-ray fluorescence. 

In 1C, the election-detection mode is the one based on conductivity measurements of solutions in which the ionic load of the eluent is low, either due to the use of eluents of low specific conductivity, or due to the chemical suppression of the eluent conductivity achieved by proper devices (see further). Nevertheless, there are applications in which this kind of detection is not applicable, e.g., for species with low specific conductivity or for species (metals) that can precipitate during the classical detection with suppression. Among the techniques that can be used as an alternative to conductometric detection, spectrophotometry, amperometry, and spectroscopy (atomic absorption, AA, atomic emission, AE) or spectrometry (inductively coupled plasma-mass spectrometry, ICP-MS, and MS) are those most widely used. Hence, the wide number of techniques available, together with the improvement of stationary phase technology, makes it possible to widen the spectrum of substances analyzable by 1C and to achieve extremely low detection limits. 

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