Inductively coupled plasma multielement analysis

In Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES), a gaseous, solid (as fine particles), or liquid (as an aerosol) sample is directed into the center of a gaseous plasma. The sample is vaporized, atomized, and partially ionized in the plasma. Atoms and ions are excited and emit light at characteristic wavelengths in the ultraviolet or visible region of the spectrum. The emission line intensities are proportional to the concentration of each element in the sample. A grating spectrometer is used for either simultaneous or sequential multielement analysis. The concentration of each element is determined from measured intensities via calibration with standards. 

The Inductively Coupled Plasma (ICP) has become the most popular source for multielement analysis via optical spectroscopy since the introduction of the first commercial instruments in 1974. About 6000 ICP-Optical Emission Spectrometry (ICP-OES) instruments are in operation throughout the world. 

Segal, I., Kloner, A., and Brenner, I. B. (1994). Multielement analysis of archaeological bronze objects using inductively coupled plasma-atomic emission spectrometry -aspects of sample preparation and spectral-line selection. Journal of Analytical Atomic Spectrometry 9 737-744. 

ICP Light emitted by atoms and monoatomic ions in an inductively coupled plasma is measured A popular technique useful over a broad concentration range multielement analysis is possible instruments are costly... 

Chapters 7 and 8 describe two major techniques for the monitoring of trace elements in environmental samples atomic absorption (AA) and inductively coupled plasma-atomic emission spectroscopy (ICP). AA is most ideally suited for analyses where a limited number of trace metal concentrations are needed with high accuracy and precision. ICP has the advantage of multielement analysis with high speed. 

Analytical Techniques Atomic absorption spectrometry, 158, 117 multielement atomic absorption methods of analysis, 158, 145 ion microscopy in biology and medicine, 158, 157 flame atomic emission spectrometry, 158, 180 inductively coupled plasma-emission spectrometry, 158, 190 inductively coupled plasma-mass spectrometry, 158, 205 atomic fluorescence spectrometry, 158, 222 electrochemical methods of analysis, 158, 243 neutron activation analysis, 158, 267. 

L. Ebdon, M. Foulkes and K. O Hanlon, Optimised simultaneous multielement analysis of environmental slurry samples by inductively coupled plasma atomic emission spectrometry using a segmented array charge-coupled device detector. Anal. Chim. Acta, 311, 1995, 123-134. 

The inductively coupled plasma13 shown at the beginning of the chapter is twice as hot as a combustion flame (Figure 21-11). The high temperature, stability, and relatively inert Ar environment in the plasma eliminate much of the interference encountered with flames. Simultaneous multielement analysis, described in Section 21 1. is routine for inductively coupled plasma atomic emission spectroscopy, which has replaced flame atomic absorption. The plasma instrument costs more to purchase and operate than a flame instrument. 

An inductively coupled plasma emission spectrometer does not require any lamps and can measure as many as —70 elements simultaneously. Color Plates 23 and 24 illustrate two designs for multielement analysis. In Plate 23, atomic emission enters the polychromator and... 

Thompson, J. J. and Houk, R. S., Inductively coupled plasma mass spectrometric detection for multielement flow injection analysis and elemental speciation by reversed phase liquid chromatography, Anal. Chem., 58, 2541-2548, 1986. 

Metals can be conveniently determined by emission spectroscopy using inductively coupled plasma (ICP). A great advantage of ICP emission spectroscopy as applied to environmental analysis is that several metals can be determined simultaneously by this method. Thus, multielement analysis of unknown samples can be performed rapidly by this technique. Another advantage is that, unlike atomic absorption spectroscopy, the chemical interference in this method is very low. Chemical interferences are generally attributed to the formation of molecular compounds (from the atoms) as well as to ionization and thermochemical effects. The principle of the ICP method is described below. 

ICP-MS is a multielement technique that is suitable for trace analysis it offers a long linear range and low background for most elements. ICP-MS is a technique where the ions produced in inductively coupled plasma are separated in a mass analyzer and detected. The sample solution is fed into a nebulizer by a peristaltic pump. The nebulizer converts the liquid sample into a fine aerosol that is transported into the plasma by an Ar gas flow. In the plasma the sample is evaporated, dissociated, atomized, and ionized to varying extents. The positive ions and molecular ions produced are extracted into the mass analyzer. Detailed descriptions of the ICP-MS technique can be found in a number of textbooks.13,14... 

Barany, E. et al., Inductively coupled plasma mass spectrometry for direct multielement analysis of diluted human blood and serum, J. Anal. At. Spectrosc., 12, 1005-1009, 1997. 

Since the introduction of the first commercial instrument in 1983, inductively coupled plasma mass spectrometry (ICP-MS) has become widely accepted as a powerful technique for elemental analysis. Two excellent books on ICP-MS have been published [1,2]. ICP-MS provides rapid, multielement analysis with detection limits at single parts part trillion or below for about 40 to 60 elements in solution and a dynamic range of 104 to 108. These are the main reasons most ICP-MS instruments have been purchased. Two additional, unique capabilities of ICP-MS have also contributed to its commercial success elemental isotope ratio measurements and convenient semiquantitative analysis. The relative sensitivities from element to element are predictable enough that semiquantitative analysis (with accuracy within a factor of 2 to 5) for up to 80 elements can be obtained using a single calibration solution containing a few elements and a blank solution. 

Marshall, J., and Franks, J. (1990) Multielement analysis and reduction of spectral interferences using electrothermal vaporization inductively coupled plasma-mass spectrometry. Atomic Spectroscopy 11, 177-186. 

Multielement analysis will become more important in industrial hygiene analysis as the number of elements per sample and the numbers of samples increases. Additional requirements that will push development of atomic absorption techniques and may encourage the use of new techniques are lower detction and sample speciation. Sample speciation will probably require the use of a chromatographic technique coupled to the spectroscopic instrumentation as an elemental detector. This type of instrumental marriage will not be seen in routine analysis. The use of Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) (17), Zeeman-effect atomic absorption spectroscopy (ZAA) (18), and X-ray fluorescence (XRF) (19) will increase in industrial hygiene laboratories because they each offer advantages or detection that AAS does not. 

R. L. Sims, L. M. Mullen, D. B. Milne, Application of inductively coupled plasma emission spectroscopy to multielement analysis of foodstuffs used in metabolic studies, J. Food. Comp. Anal., 3 (1990), 27-37. 

Inductively coupled plasma mass spectrometry (ICP-MS) is one of the most significant analytical advances to occur in the last 20 years as it allows multielement analysis of solutions and solids to be performed at subnanogram concentrations. Instrumental advances have occurred such that Quadrupole (Q) ICP-MS units are now in routine use in many laboratories. In this chapter, the use of Q-ICP-MS and high performance liquid chromatography (HPLC)-ICP-MS is discussed as regards the quantification of total As and As species in seafood. To highlight the strengths and weaknesses of the use of ICP-MS, data are used that were mainly produced in the laboratories of the authors of this chapter. 

Each spectroscopic method has a characteristic application. For example, flame photometry is still applicable to the direct determination of Ca and Sr, and to the determination of Li, Rb, Cs and Ba after preconcentration with ion-exchange resin. Fluorimetry provides better sensitivities for Al, Be, Ga and U, although it suffers from severe interference effects. Emission spectrometry, X-ray fluorescence spectrometry and neutron activation analysis allow multielement analysis of solid samples with pretty good sensitivity and precision, and have commonly been applied to the analysis of marine organisms and sediments. Recently, inductively-coupled plasma (ICP)... 

Contamination of the analytes from the carriers (the precipitates) should be first examined, and the blank test carried out carefully. Great care should also be taken in terms of the recoveries of the analytes, because the procedures in the coprecipitation are sometimes time-consuming and irre-producible. Some efficiencies of recovery for Zr(IV) coprecipitation along with the determined values of trace elements in seawater are summarized in Table 7, where inductively-coupled plasma (ICP) emission spectrometry was applied for the simultaneous multielement analysis [45]. In this experiment, 10 mg of Zr(IV) was added to 11 of seawater, the precipitation made... 

In both total and sequential dissolutions, the result is a solution containing the components of rocks and soils. This solution is then analyzed by different methods. Mostly, spectroscopic methods are used atomic absorption and emission spectroscopic methods, ultraviolet, atom fluorescence, and x-ray fluorescence spectrometry. Multielement methods (e.g., inductively coupled plasma optical emission spectroscopy) obviously have some advantages. Moreover, elec-troanalytical methods, ion-selective electrodes, and neutron activation analysis can also be applied. Spectroscopic methods can also be combined with mass spectrometry. 

Kuennen, R.W., Wolnik, K.A., Fricke, F.L., Caruso, J.A. Pressure dissolution and real sample matrix calibration for multielement analysis of raw agriculture crops by inductively coupled plasma atomic emission spectrometry. Anal. Chem. 54, 2146-2150 (1982)... 

This chapter discusses the advantages and limitations of the multielement analysis of biologically related samples using induction-coupled plasma optical emission. The sample categories covered include grains, feeds, fish, bovine liver, orchard leaves, and human kidney stones. These materials have been simultaneously analyzed for copper, nickel, vanadium, chromium, phosphorus, cobalt, lead, potassium, zinc, manganese, iron, strontium, sodium, aluminum, calcium, magnesium, silicon, boron, and beryllium, often with limited amounts of sample. 

The latest study has revealed that CCC has a great potential in the ultratrace determination of metals, because it can concentrate minute amounts of metal prior to the instrumental multielement analysis, such as atomic absorption spectrometry (AAS), inductively coupled plasma-atomic emission spectrometry (ICP-AES), and inductively coupled plasma-mass spectrometry (ICP-MS). 

Over the past decade Inductively Coupled Plasma (ICP) sources, in particular coupled with Mass Spectrometry (MS) instruments, have shown an immense potential for multielement analysis in environmental samples (88). These capabilities have been obtained thanks to the combination of the great ionization energy of a plasma source with the high sensitivity and selectivity of the mass spectrometric detector. Since polar snow and ice are considered as the purest material on the earth surface, these environmental matrices constitute the ideal samples for ICP-MS since potential interferences formed in the plasma are kept at a minimum level. 

Brenner J. B., Zander A., Cole M. and Wiseman A. (1997) Comparison of axially and radially viewed inductively coupled plasmas for multielement analysis. Effect of sodium and calcium, J Anal At Spectrom 12 897-906. 

Moore G. L., Humphries-Cuff P. J. and Watson A. E. (1984) Simplex optimization of a nitrogen-cooled argon inductively coupled plasma for multielement analysis, Spectrochim Acta, Part B 39 915-929. 

Phosphorus can serve as a benehcial adjunct or as a deleterious agent. There are several test methods for the determination of phosphorus. In addition to the three test methods described here, reference should also be made to multielement analysis methods such as inductively coupled plasma atomic emission spectroscopy (ICPAES) (ASTM D-4951, ASTM D-5185) and X-ray fluorescence (XRF) (ASTM D-4927, ASTM D-6443) described above in this guide. Phosphorus can also be determined by a photometric procedure (IP 148) or by a test method (ASTM D-1091) in which the organic material in the sample is destroyed, phosphorus in the sample is converted to phosphate ion by oxidation with sulfuric acid, nitric acid, and hydrogen peroxide, and the magnesium pyrophosphate is determined gravimetrically. Another method (ASTM D-4047, IP 149) in which the phosphorus is converted to quinoline phosphomolybdate is also available. 

Taylor VF, Longerich HP and Greenough JD (2003) Multielement analysis of Canadian wines by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and multivariate statistics. J Agric Food Chem 51 856-860. 

Amaeasieiwaedena D, Kotebai M, Keushevska A and Baenes RM (1997) Multielement analysis of human milk by inductively coupled plasma mass and atomic emission spectrometry after high pressure, high temperature digestion. Can J Anal Sci Spectrosc 42 69-78. 

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