Inductively coupled plasma-mass spectrophotometry

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 modern times, most analyses are performed on an analytical instrument for, e.g., gas chromatography (GC), high-performance liquid chromatography (HPLC), ultra-violet/visible (UV) or infrared (IR) spectrophotometry, atomic absorption spectrometry, inductively coupled plasma mass spectrometry (ICP-MS), mass spectrometry. Each of these instruments has a limitation on the amount of an analyte that they can detect. This limitation can be expressed as the IDL, which may be defined as the smallest amount of an analyte that can be reliably detected or differentiated from the background on an instrument. 

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. 

Inductively coupled plasma atomic emission spectrometry and inductively coupled plasma mass spectrometry have been applied to the determination of zinc, as discussed under Multi-Metal Analysis of Soils in Sects. 2.55 (inductively coupled plasma atomic emission spectrometry) and 2.55 (inductively coupled plasma mass spectrometry). Other techniques include atomic absorption spectrometry (Sect. 2.55), X-ray fluorescence spectroscopy (Sect. 2.55), electron probe microanalysis (Sect. 2.55), photon activation analysis (Sect. 2.55), emission spectrometry (Sect. 2.55), neutron activation analysis (Sect. 2.55), spectrophotometry (Sect. 2.55) and ion chromatography (Sect. 2.55). 

Analytical techniques used for clinical trace metal analysis include photometry, atomic absorption spectrophotometry (AAS), inductively coupled plasma optical emission (ICP-OES), and inductively coupled plasma mass spectrometry (ICP-MS). Other techniques, such as neutron activation analysis (NAA) and x-ray fluorescence (XRF), and electrochemical methods, such as anodic stripping voltammetry (ASV), are used less commonly For example. NAA requires a nuclear irradiation facility and is not readily available and ASV requires completely mineralized solutions for analysis, which is a time-consuming process. 

Analytical Methods and Speclatlon Electrothermal atomic absorption spectrophotometry (ETAAS), differential pulse adsorption voltammetry (DPAV), isotope-dilution mass spectrometry (ID-MS), and inductively coupled plasma mass spectrometry (ICP-MS) furnish the requisite sensitivity for measurements of nickel concentrations in biological, technical and environmental samples (Aggarwal et al. 1989, Case et al. 2001, Stoeppler and Ostapczuk 1992, Templeton 1994, Todorovska et al. 2002, Vaughan and Templeton 1990, Welz and Sperling 1999). The detection limits for nickel determinations by ETAAS analysis with Zeeman background correction are approximately 0.45 jg for urine,... 

Minoia, C., Sabbioni, E., Apostoli, P., Pietra, R.. Pozzoli, L, Gallorini, M., Nicolaou, G.. Alessio, L., and Capodaglio, E. (1990). Trace element reference values in tissues from inhabitants of the european community I. A study of 46 elements in urine, blood and serum of Italian subjects, Sci. Total Environ., 25.89-105 Olsen. A.D., and Hamlin, W.B. (1968). Serum copper and zinc by atomic absorption spectrophotometry. Atom. Absorpt. Newsl., Z, 69-71 Plantz, M.R., Fritz, J.S., Smith, F.G., and Houk, R.S. (1989). Separation of trace metal complexes for samples of high salt content by inductively coupled plasma mass spectrometry, Anal. Chem., 1,149-153... 

These are among the most harmful pollutants in sewage. Essential elements (e.g., Fe) as well as toxic metals such as Cd, Hg, and Pb are included. Main sources of heavy metals are industrial wastes, mining, fuels, coal, metal plating, etc. Metal determinations in sewage are preferably carried out by atomic spectrometry (flame and electrothermal atomization), atomic emission spectrometry, inductively coupled plasma-mass spectrometry, stripping voltammetry, spectrophotometry, and kinetic methods. Hg is advantageously determined by the cold vapor technique and As by the hydride technique. 

For determination of the elements, mainly spectrometric techniques are used here. Depending on the kind of element and the expected concentration level, the following methods are applied flame atomic emission spectrometry (flame AES), flame atomic absorption spectrometry (flame AAS), inductively coupled plasma optical emission spectrometry (ICP-OES), electrothermal atomisation (graphite furnace) atomic absorption spectrometry (ETA-AAS), inductively coupled plasma mass spectrometry (ICP-MS), spectrophotometry and segmented flow analysis (SFA). Besides, potentiometry (ion selective electrodes (ISE)) and coulometry will be encountered. In many cases, more than one method is described to determine a component. This provides a reference, as well as an alternative in case of instrumental or analytical problems. 

One of the most challenging aspects of atomic spectrometry is the incredibly wide variety of sample types that require elemental analysis. Samples cover the gamut of solids, liquids, and gases. By the nature of most modem spectrochemical methods, the latter two states are much more readily presented to sources that operate at atmospheric pressure. The most widely used of these techniques are flame and graphite furnace atomic absorption spectrophotometry (FAAS and GF-AAS) [1,2] and inductively coupled plasma atomic emission and mass spectrometries (ICP-AES and MS) [3-5]. As described in other chapters of this volume, ICP-MS is the workhorse technique for the trace element analysis of samples in the solution phase—either those that are native liquids or solids that are subjected to some sort of dissolution procedure. 

Problems with contamination and losses of volatile boron compounds during sample preparation have limited the reliable documentation of boron concentrations in human tissue and body fluids. A complex technique involving a porous graphite column—inductively coupled plasma-atomic emission spectrophotometry (ICP-AES)— and an ICP time of flight mass spectrometer (TOF-MS) has been developed for investigations of boron neutron capture in cancer therapy. Adaptation of this method to nutritional studies of boron should be possible. 

A number of analytical techniques have been used to determine ppm to ppt levels of vanadium in biological materials. These include neutron activation analysis (NAA), graphite furnace atomic absorption spectrometry (GFAAS), spectrophotometry, isotope dilution thermal ionization-mass spectrometry (IDMS), and inductively coupled plasma atomic emission spectrometry (ICP-AES). Table 6-1 summarizes the analytical methods for determining vanadium in biological materials. 

The chemical methods for detecting total strontium include spectrophotometry, fluorometry, kinetic phosphorescence, atomic absorption spectroscopy (e.g., flame and graphite furnaces), inductively coupled plasma spectroscopy atomic emission and mass spectrometry applications (i.e., ICP-AES and ICP-MS). 

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