ICP atomic emission spectrometry

The extension of inductively coupled plasma (ICP) atomic emission spectrometry to seawater analysis has been slow for two major reasons. The first is that the concentrations of almost all trace metals of interest are 1 xg/l or less, below detection limits attainable with conventional pneumatic nebulisation. The second is that the seawater matrix, with some 3.5% dissolved solids, is not compatible with most of the sample introduction systems used with ICP. Thus direct multielemental trace analysis of seawater by ICP-AES is impractical, at least with pneumatic nebulisation. In view of this, a number of alternative strategies can be considered ... 

There is also a standard test method for determination of major and minor elements in coal ash by inductively coupled plasma (ICP)-atomic emission spectrometry (ASTM D-6349). In the test method, the sample to be analyzed is ashed under standard conditions and ignited to constant weight. The ash is fused with a fluxing agent followed by dissolution of the melt in dilute acid solution. Alternatively, the ash is digested in a mixture of hydrofluoric, nitric, and hydrochloric acids. The solution is analyzed by (ICP)-atomic emission spectrometry for the elements. The basis of the method is the measurement of atomic emissions. Aqueous solutions of the samples are nebulized, and a portion of the aerosol that is produced is transported to the plasma torch, where excitation and emission occurs. Characteristic line emission spectra are produced by a radio-frequency inductively coupled plasma. A grating monochromator system is used to separate the emission lines, and the intensities of the lines are monitored by photomultiplier tube or photodiode array detection. The photocurrents from the detector... 

Coal contains several elements whose individual concentrations are generally less than 0.01%. These elements are commonly and collectively referred to as trace elements. These elements occur primarily as part of the mineral matter in coal. Hence, there is another standard test method for determination of major and minor elements in coal ash by ICP-atomic emission spectrometry, inductively coupled plasma mass spectrometry, and graphite furnace atomic absorption spectrometry (ASTM D-6357). The test methods pertain to the determination of antimony, arsenic, beryllium, cadmium, chromium, cobalt, copper, lead, manganese, molybdenum, nickel, vanadium, and zinc (as well as other trace elements) in coal ash. 

Hoffmann and Lieser [112] used XFS to determine a range of elements in leaves and grass and compared this technique with neutron activation analysis, AAS, ICP-atomic emission spectrometry, polarography and voltammetry. 

The most important analytical techniques which are used in multielement trace analysis are ICP-MS, atomic absorption spectrometry (AAS) and ICP atomic emission spectrometry (AES). NAA is applied as reference method in order to establish certibed values. The regular atomic spectrometry update on clinical and biological materials, foods and beverages (ASU review) gives an overview of the recent developments in elemental analysis of food and beverages [81]. 

Fuishiro, M., Kubota, M. and Ishida, R. (1984) A study of designs of cross flow nebulisers for ICP atomic emission spectrometry, Spectrochimica Acta, Part B, 39, pp617-620. 

These two-dimensional detectors [63] are ideally suited for coupling with an echelle spectrometer, which is state of the art in modem spectrometers for ICP atomic emission spectrometry as well as for atomic absorption spectrometers. As for CCDs the sensitivity is high and along with the signal-to-noise ratios achievable, they have become real alternatives to photomultipliers for optical atomic spectrometry (Table 3) and will replace them more and more. 

Au and Ir, requiring cryocooling to eliminate it. Accuracy and precision were in the range 10-15 and 5-10%, respectively, while the power of detection turned out to be better by 1-2 orders of magnitude than in ICP atomic emission spectrometry. 

Today, analyses of bulk fossil chemistry are largely conducted by inductively coupled plasma (ICP) atomic emission spectrometry (AES), ICP mass spectrometry (MS) or ICP optical emission spectrometry (OES) techniques (e.g. Rosenthal et al. 1999 DeVilliers et al. 2002 Green et al. 2003). These techniques permit rapid and precise (c. 1% for many elements) measurement of a number of chemical constituents simultaneously. ICP-MS offers higher sensitivities than AES and OES, enabling measurement of more elements and smaller sample sizes. 

Metals Hg, Pb, Cd, Ca, Mg Fe, Mn, Al Flame and cold-vapour atomic absorption. ICP atomic emission spectrometry. Graphite furnace. Zeeman effect. Anodic stripping voltammetry. X-ray fluorescence. ISEs. Colorimetry... 

Hirano and Suzuki (1996) have summarized detection limits of the various ions in the lanthanide series for four analytical methods. The most sensitive method for analysis of lanthanides is inductively coupled plasma-mass spectrometry (ICP-MS), where detection limits for the series of ions range from 0.002 to 0.009 Jg L with the exception of Sm (limit of 1.5 Detection limits for lanthanides using ICP-atomic emission spectrometry (ICP-AES) range from 0.02 to 30 jg L h The sensitivity... 

Problems and Limitations Unfortunately, derivatization is sometimes less selective than expected (Quevauviller et al. 1996), and the detector response is also species-derivative specific, which must be considered in quantification. Some of the derivatives, however, have almost no detector response (Mota and Simaes-Gon-calves 1996). As the separation typically is carried out at elevated temperature, only thermally stable species can be handled by GC. Another problem arises when coupling GC to element-selective detectors, such as ICP-atomic emission spectrometry (ICP-AES) or ICP-MS. The transfer line must also be heated up to the plasma, either by a pre-heated sheath gas (Orellana-Velado... 

Human biological materials to be investigated include (a) hard calcified tissues, e.g. bone, teeth, other calcified formations (b) semi-hard tissue, e.g. hair, nails (c) soft body tissues and (d) various biological fluids and secretions in the human body. The treatment of each of these materials varies from one material to another and, as stated earlier, is often determined by the instrumental method to be employed for measuring the analytical signal, the elements to be determined and the concentration levels at which these are present. For the purposes of this discussion, it shall be generally assumed that the analytical techniques employed include atomic absorption spectrometry both with (F-AAS) as well as with a furnace (GF-AAS), neutron activation analysis (NAA), flame emission spectrometry (FES) voltammetric methods and the three inductively coupled plasma spec-trometric methods viz. ICP-atomic emission spectrometry, ICP-mass spectrometry and ICP-atomic fluorescence spectrometry. The sample preparation of biological methods for all ICP techniques is usually similar (Guo, 1989). 

Figure 6 Partitioning of LiCl between water and 1-octanol at 25°C, as taken from ref. [2l6]. The lithium distribution ratios Du were determined at 1 1 initial phase ratio by use of ion chromatography (IC), inductively coupled plasma (ICP) atomic emission spectrometry, and Li NMR spectrometry. A correction was made for the slight volume changes due to the mutual solubility of 1-octanol and water. Error bars are indicated only for the ICP data, which were the least precise data obtained by the three techniques. The solid curved line represents the equilibrium model calculated by SXLSQl using the values of log/Cs= = —6.85 and logX, = — 2.74 (Table 12). The dashed curved line is an extrapolation of the model to indicate the approach to the calculated asymptotic value of the distribution ratio at infinite dilution (3.76 X 10...

Modern analytical such as infrared (IR) spectroscopy, liquid chromatography (LC), and gas-liquid chromatography (GLC) are in use for the identification of organic components, whilst the mineral constituents can be estimated by using X-ray fluorescence (XRF) spectrometry. X-ray diffraction (XRD), atomic absorption spectrometry (AAS), or inductively coupled plasma (ICP) atomic emission spectrometry (AES). 

A range of chromatographic techniques coupled to element specific detectors has been used in speciation studies to separate individual organometallic species (e.g., butyltins, arsenic species) and to separate metals bovmd to various biomolecules. The combination of a chromatographic separation with varying instrumental detection systems are commonly called coupled, hybrid, or hyphenated techniques (e.g., liquid chromatography inductively coupled plasma-mass spectrometry (LC-ICP-MS), gas chromatography-atomic absorption spectroscopy (GC-AAS)). The detection systems used in coupled techniques include MS, ICP-MS, atomic fluorescence spectrometry (AFS), AAS, ICP-atomic emission spectrometry (ICP-AES), and atomic emission detection (AED). 

The following three analytical techniques have been developed for multielement determination after oxygen flask combustion inductively coupled plasma (ICP)-atomic emission spectrometry (AES), IC, and RNAA. ICP-AES is mainly used for trace metal analysis and RNAA for multiple isotope determination in inorganic materials. From the summary of new procedures developed since 1995 using the oxygen flask method for elemental analysis listed in Table 1, it is clear that IC is the major analytical technique behind the recent development of multielement determination for oxygen flask combustion, in particular for organic samples. 

Many methods used for qualitative analysis are destructive either 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 ICP atomic emission spectrometry (ICP-AES or ICP optical emission spectrometry [ICP-OES]), discussed in Chapter 7, and ICP-MS, discussed in Chapters 9 and 10. These techniques can identify almost all the elanents 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 this 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 process. The advantage of ICP-OES and ICP-MS is that they are very sensitive concentrations at or below 1 ppb of most elements can be detected using these methods. 

To achieve high sensitivity when analyzing trace inorganic elements in a sample solution using an atomic absorption spectrometry (AAS) or Inductively coupled plasma (ICP) atomic-emission spectrometry (ICP-AES), conventional preconcentration methods such as evaporation, ion exchange, and solvent extraction techniques have... 

As examples of Ti measurements, the application of ICP-atomic emission spectrometry to the analysis of bone [14], of proton nuclear activation (PNA) to serum [8], and of particle-induced X-ray emission (PIXE) to lung tissue [15] are described in Sec. 4.2. The authors of these studies report measurements at the level of 0.2-0.5 p.g/g in bone, 10 xg/g in lung, and 90 p.g/liter in serum. However, it must be stressed that there is insufficient comparative data to coimnent on the accuracy of these results. Further, these were all multielement investigations and sampling procedures were not specific to Ti. 

Conventional ICP atomic emission spectrometry (ICP-AES) is not sensitive enough to allow the determination of dissolved trace elements in seawater. It might, however, majorly be applied in the analysis of collected particulate material. The technique combines fast multi-element measurements with somewhat lower investment costs when compared with ICP-MS (see Section 12.6). 

Annual Book ofATSM Standard, ASTM-D5708 (2002), Standard test method for determination of nickel, vanadium and iron in crude oils and residual fuels by inductively coupled plasma (ICP) atomic emission spectrometry, American Society for Testing and Materials, West Conshohockm, PA. 

Shibata,Y. (19%). Inductively coupled plasma (ICP) atomic emission spectrometry and ICP mass spectrometry Their biomedical and environmental applications. Eisei Kagaku 42(5), 385. 

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