Inductive coupled plasma with mass

AAS = atomic absorption spectrometry GC/FID = gas chromatography/f1ame ignition detector GC/FPD = gas chromatography/f1ame photometric detector ICP/AES = inductively coupled plasma atomic emission spectroscopy ICP/MS = inductively coupled plasma with mass spectrometric detection... 

Sensing methods capable of quantifying these trace elements at low levels include atomic absorption spectroscopy (AAS), inductively coupled plasma (ICP) combined with atomic emission spectrometry (ICP-AES) or inductively coupled plasma with mass spectrometry (ICP-MS). The latter technique represents a powerful... 

Samples to be examined by inductively coupled plasma and mass spectrometry (ICP/MS) are commonly in the form of a solution that is transported into the plasma flame. The thermal mass of the flame is small, and ingress of excessive quantities of extraneous matter, such as solvent, would cool the flame and might even extinguish it. Even cooling the flame reduces its ionization efficiency, with concomitant effects on the accuracy and detection limits of the ICP/MS method. Consequently, it is necessary to remove as much solvent as possible which can be done by evaporation off-line or done on-line by spraying the solution as an aerosol into the plasma flame. 

With the advent of multiple-collector inductively coupled plasma-source mass spectrometry (MC-ICPMS) it is now possible to measure Mg/ Mg and Mg/ Mg of Mg in solution with a reproducibility of 30 to 60 ppm or better (Galy et al. 2001). What is more, ultraviolet (UV) laser ablation combined with MC-ICPMS permits in situ analysis of Mg-bearing mineral samples with reproducibility of 100 to 200 ppm (Yoimg et al. 2002a). These new analytical capabilities allow mass-dependent fractionations of the isotopes of Mg to be used as tracers in natural systems. 

The observed range of natural variations of 5 Ca is about 4 to 5%o in terrestrial materials and up to 50%o in high temperature condensate minerals in carbonaceous chondrites. The typical reproducibility of measurements is about +0.15%o. Broader application of Ca isotope measurements in geochemistry may be possible, particularly if the reproducibility can be improved to 0.05%o to 0.03%o. There is hope that this can be achieved either with inductively coupled plasma source mass spectrometry (Halicz et al. 1999) or with a new generation of multi-collector thermal ionization mass spectrometers (Heuser et al. 2002). 

Ag, Cl, and N to six-figure accuracy.1 This Nobel Prize-winning research allowed the accurate determination of atomic masses of many elements. In combustion analysis, a sample is burned in excess oxygen and products are measured. Combustion is typically used to measure C, H, N, S, and halogens in organic compounds. To measure other elements in food, organic matter is burned in a closed system, the products and ash (unburned material) are dissolved in acid or base, and measured by inductively coupled plasma with atomic emission or mass spectrometry. 

The method combines an inductively coupled plasma with a quadrupole mass spectrometer. High energy ICP generates singly charged ions from the atoms of the elements present in the sample. Such ions are now directed onto the mass spectrometer, separated, and measured according to their mass-to-charge ratio. 

Isotope ratios provide insight into the physical and chemical processes that cause alteration of their values. Their application is expanding as analytical procedures become more sophisticated and sensitive, and as the extent of scientific knowledge increases. As in many fields, much work done today would have been impossible a few years ago. With the advent of multicollector inductively coupled plasma (ICP) mass spectrometers, it is probable that routine use of thermal ionization will diminish, but it seems that it will always play a role in applications in which utmost sensitivity is required. 

Russ, G.R III, and Bazan, J.M. (1987) Isotopic ratio measurements with an inductively coupled plasma source mass spectrometer. Spectrochim. Acta 42B, 49-62. 

Figure 21 Ultrahigh mass resolving power inductively coupled plasma (ICP) mass spectrum that demonstrates separation of 40Ca+ from 40Ar+ obtained with a Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer equipped with a 3-tesla superconducting magnet.

M. Muller, K. G. Heumann, Isotope dilution inductively coupled plasma quadrupole mass spectrometry in connection with a chromatographic separation for ultra-trace determinations of platinum group elements (Pt, Pd, Ru, Ir) in environmental samples, Fresenius J. Anal. Chem., 368 (2000), 109D115. 

Analysis of Al can be routinely performed by inductively coupled plasma (ICP) mass spectrometry (ICP-MS). Alternatively, atomic absorption spectrometry with electrothermal atomization may be employed, but considerable attention must be paid to matrix interferences. 

The most utilized methods include X-ray fluorescence (XRF), atomic absorption spectroscopy (AAS), activation analysis (AA), optical emission spectroscopy (OES) and inductively coupled plasma (ICP), mass spectroscopy (MS). Less frequently used techniques include ion-selective electrode (ISE), proton induced X-ray emission (PIXE), and ion chromatography (IC). In different laboratories each of these methods may be practiced by using one of several optional approaches or techniques. For instance, activation analysis may involve conventional thermal neutron activation analyses, fast neutron activation analysis, photon activation analysis, prompt gamma activation analysis, or activation analysis with radio chemical separations. X-ray fluorescence options include both wave-length and/or energy dispersive techniques. Atomic absorption spectroscopy options include both conventional flame and flameless graphite tube techniques. 

More recently for ultratrace determination and speciation of antimony compounds the so-called hyphenated instrumental techniques have been applied which combine adequate separation devices with suitable element-specific detectors. They include high-performance liquid chromatography (HPLC) connected on-line with heated graphite furnace (HGF) AAS (HPLC-HGF-AAS), hydride-generation atomic fluorescence spectrometry (HPLC-HG-AFS) or inductively coupled plasma (ICP) mass spectrometry (MS) (HPLC-ICP-MS) capillary electrophoresis (CE) connected to inductively coupled plasma mass spectrometry (CE-ICP-MS) and gas chromatography (GC) coupled with the same detectors as with HPLC. Reliable speciation of antimony compounds is still hampered by such problems as extractability of the element, preservation of its species information, and availability of Sb standard compounds (Nash et al. 2000, Krachler etal. 2001). Variants of anodic stripping voltammetry for speciation of antimony have also been applied (Quentel and Eilella 2002). 

Muller M, Heumann KG (2000) Isotope dilution inductively coupled plasma quadmpole mass spectrometry in connection with a chromatographic separation for ultra trace determinations... 

Delville and co-workers selected 20 nm Si02 and 13 nm AI2O3 from commercial sources as particulate substrates for the attachment of aminopropyltrimethoxysilyl (APS) GdDTPA. The derivatized particles were prepared either by amination followed by reaction with DTPA bis(anhydride), or by peptide coupling of the particle surface amines with DTPA. The grafting of APS on sUica, as monitored by DRIFTS, resulted in the disappearance of Si-OH bands, and the appearance of the expected CH2 and carbonyl peaks of DTPA. XPS data established that Gd constituted about 4 atom % of silica, and 2 atom % of AI2O3. In this system there arc approximately 4 Gd complexes per silica particle as determined by inductively coupled plasma (ICP) mass spectrometry, with an average relaxivity. 

Automotive accidents are investigated by analyzing glass and paints. One way to match the glass from a broken windshield found at a hit-and-run accident scene is to compare elemental profiles. Inductively coupled plasma (ICP) mass spectrometry is an ideal method for this purpose [67]. Acid digestion is used for sample preparation. The use of laser ablation, coupled with ICP-MS, obviates the need for the laborious and time-consuming acid-digestion step [68]. 

The detectors used in HTGC are, apart from the highly versatile flame ionization detector (FID), the phosphorus/nitrogen-selective alkali-flame ionization detector (AFID), the atomic emission detector, the inductively coupled plasma (ICP)-mass spectrometer, and, last but not least, mass spectrometers with electron impact and chemical ionization ion sources (EI/CI-MS). 

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