Inductively coupled plasma mass spectrometry instrument

Gray, A.R., and Williams, J.G. (1987) Oxide and doubly charged ion response of a commercial inductively coupled plasma mass spectrometry instrument. J. Anal. Atomic Spectrom. 2, 81-82. 

Jakubowski, N., Feldmann, I., and Stuewer, D. (1997). Grimm-type glow discharge ion source for operation with a high resolution inductively coupled plasma mass spectrometry instrument./. Ana/. At. Spectrom. 12(2), 151. 

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 contrast to thermal ionization methods, where the tracer added must be of the same element as the analyte, tracers of different elemental composition but similar ionization efficiency can be utilized for inductively coupled plasma mass spectrometry (ICPMS) analysis. Hence, for ICPMS work, uranium can be added to thorium or radium samples as a way of correcting for instrumental mass bias (e g., Luo et al. 1997 Stirling et al. 2001 Pietruszka et al. 2002). The only drawback of this approach is that small inter-element (e g., U vs. Th) biases may be present during ionization or detection that need to be considered and evaluated (e.g., Pietruszka et al. 2002). 

In isotope dilution inductively coupled plasma-mass spectrometry (ID-ICP-MS) the spike, the unspiked and a spiked sample are measured by ICP-MS in order to determine the isotope ratio. Using this technique, more precise and accurate results can be obtained than by using a calibration graph or by standard addition. This is due to elimination of various systematic errors. Isotopes behave identically in most chemical and physical processes. Signal suppression and enhancement due to the matrix in ICP-MS affects both isotopes equally. The same holds for most long-term instrumental fluctuations and drift. Accuracy and precision obtained with ID-ICP-QMS are better than with other ICP-QMS calibration... 

Inductively coupled plasma mass spectrometry is now such an important technique in archaeology, as elsewhere, that we devote a whole chapter to it. There are now a number of different ICP MS modes of operation (solution analysis, laser ablation, multicollector, high resolution) this chapter provides a general overview. Further description of the instrumentation for ICP MS may be found in Harris (1997) and Montaser (1998). Some general applications of solution ICP MS are discussed by Date and Gray (1989), Platzner (1997), and Kennett et al. (2001). 

Zheng, J., Goessler, W., Geiszinger, A., et al. (1997). Multi-element determination in earthworms with instrumental neutron activation analysis and inductively coupled plasma mass spectrometry a comparison. Journal of Radioanalytical and Nuclear Chemistry 223 149-155. 

Turner PJ, Mills DJ, Schroder E, Lapitajs G, Jung G, lacone LA, Haydar DA, Montaser A(1998) Instrumentation for low- and high-resolution ICPMS. In Inductively Coupled Plasma Mass Spectrometry. Montaser A (ed), Wiley-VCH, New York, p 421-501... 

Cations were determined by high-resolution inductively coupled plasma-mass spectrometry (HR-ICPMS), relatively new analytical instrumentation with a large dynamic range and detection limits (DLs) in the low (1-50) parts per trillion (ppt) for most elements. The exceedingly low DLs allow for recognition of elemental variations that are not possible with traditional analytical methods for water. 

Numerous methods have been published for the determination of trace amounts of tellurium (33—42). Instrumental 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 instrumental methods include polarography, potentiometry, emission spectroscopy, x-ray diffraction, and x-ray fluorescence. 

The success of inductively coupled plasma mass spectrometry (ICP-MS) has resulted in a broad availability of sophisticated instrumentation packages with user-friendly software and sample-analysis cookbooks at reasonable cost [10]. 

Fundamentals and Basic Instrumentation of Inductively Coupled Plasma Mass Spectrometry... 

Figure 21-24 Flame, furnace, and inductively coupled plasma emission and inductively coupled plasma—mass spectrometry detection limils (ng/g = ppb) with instruments from GBC Scientific Equipment, Australia. [Flame, furnace. ICP from R. J. Gill. Am. Lab. November 1993, 24F. ICP-MS from T. T. Nham, Am. Lab. August 1998. 17A Data for Ct Br, and l are from reference 14.] Accurate quantitative analysis requires concentrations 10-100 times greater than the detection limit.

Trace elemental analysis of ancient ceramics has been proven a very useful tool for tracing the circulation of this material. Instrumental neutron activation analysis (INAA) was for years the analytical technique of choice to measure the composition of ceramics because of the large number of elements it could determine and its good sensitivity. Lately, a few publications have shown that laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) could provide similar results as INAA more quickly and at lower cost. A protocol has been developed to determine 51 elements using LA-ICP-MS and tested it on Wari period ceramics previously analyzed using INAA. We show how INAA and LA-ICP-MS analysis lead to the same conclusion in terms of sample groupings. 

Kimbrough and Wakakuwa [276,330] reported on an interlaboratory comparison study involving 160 accredited hazardous materials laboratories. Each laboratory performed a mineral acid digestion on five soils spiked with arsenic, cadmium, molybdenum, selenium and thallium. The instrumental detection methods used were inductively coupled plasma atomic emission spectrometry, inductively coupled plasma mass spectrometry, flame atomic absorption spectrometry, electrothermal atomic absorption spectrometry and hydride generation atomic absorption spectrometry. At most concentrations, the results obtained with inductively coupled plasma atomic emission spectrometry... 

The determination of 129I in low-level radioactive waste was accomplished by radioactive instrumental neutron activation analysis [3]. A different group reported the determination of both 129I and 127I by neutron activation analysis and inductively coupled plasma mass spectrometry [4]. The method was very rapid - a sample could be analysed in three minutes. However, interference from 129Xe resulted in limited sensitivity for 129I detection. 

IATA ICAP ICP ICP-AES ICP-MS ICV ID IDL IDW ISO International Air Transportation Association inductively coupled argon plasma inductively coupled plasma inductively coupled plasma-atomic emission spectrometry inductively coupled plasma-mass spectrometry initial calibration verification identification instrument detection limit investigation-derived waste International Standardization Organization... 

The table below lists some common spectral interferences that are encountered in inductively coupled plasma mass spectrometry (ICP-MS), as well as the resolution that is necessary to analyze them.1 The resolution is presented as a dimensionless ratio. As an example, the relative molecular mass (RMM) of the polyatomic ion 15N160+would be 15.000108 + 15.994915 = 30.995023. This would interfere with 31P at a mass of 30.973762. The required resolution would be RMM/8RMM, or 30.973762/0.021261 = 1457. One should bear in mind that as resolution increases, the sensitivity decreases with subsequent effects on the price of the instrument. Note that small differences exist in the published exact masses of isotopes, but for the calculation of the required resolution, these differences are trivial. Moreover, recent instrumentation has provided rapid, high-resolution mass spectra with an uncertainty of less than 0.01%. 

Rosen, A.L. and G.M. Hieftje. 2004. Inductively coupled plasma mass spectrometry and electrospray mass spectrometry for speciation analysis Applications and instrumentation. Spectrochim. Acta B 59 135-146. 

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. 

Figure 1 Schematic diagram of a typical commercial inductively coupled plasma mass spectrometry (ICP-MS) instrument (A) liquid sample, (B) peristaltic pump, (C) nebulizer, (D) spray chamber, (E) argon gas inlets, (F) load coil, (G) sampler cone, (H) skimmer cone, (I) ion lenses, (J) quadrupole, (K) electron multiplier detector, (L) computer.

Figure 13 Scheme of coupling of the gas chromatograph (GC) with the inductively coupled plasma mass spectrometry (ICP-MS) instrument (1) torch (2) injector supply (3) Teflon piece + Teflon Swagelok adapter (4) Swagelok T-joint (5) commercial transfer line (6) stainless steel transfer tube (7) transfer capillary. (From Ref. 91.)... 

Figure 15 Supercritical fluid chromatography inductively coupled plasma mass spectrometry (SFC-ICP-MS) instrument diagram showing a SFC-ICP interface. (From Ref. 116.)...

A plasma source was coupled to a TOF-MS as early as the 1960s, when workers at Bendix [12] used such an arrangement to analyze the chemical species in a plasma jet. The instrument utilized a pulsed supersonic inlet probe similar to that found in current inductively coupled plasma mass spectrometry (ICP-MS) quadru-pole instruments and employed a TOF-MS that was oriented at a 90° angle to the input ion beam. More importantly, however, it used a pulsed extraction field to extract ions from the plasma source and accelerate them into the flight tube. It is this concept of injecting discrete ion bunches into the TOF-MS analyzer that has been almost ubiquitously employed by workers using continuous ion sources [17,18]. 

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