Plasma Ionization Mass Spectrometry

In this method designed for the analysis of inorganic solutions, ionization occurs at atmospheric pressure. 

The sample solution is injected into the ion source, dispersed in a carrier gas and ionized by an electric discharge between two electrodes. A quadrupole analyzer is used for the resolution of the ion beam. 

An example for plasma ion mass spectrometry is the investigation of a silver solution at a concentration of 3 mg/1 When a sample of this solution is nebulized, 

The isotopic peaks of silver Ag and ° Ag suggest a high sensitivity for this metal. Metal impurities of Na, Cu and Cu are detected besides peaks due to organic ions. Furthermore, corresponding to m/z 19 (OHj ) and m/z 30 (NO ) which come from nitrogen, oxygen, carbon dioxide, and water present in the carrier gas argon are found. The method of plasma ion mass spectrometry is very sensitive and only small amounts of sample are used. The detection limit for some metals (Ag, As, Co, Pb) is below 1 ppb. 

FDMSi is a soft ionization technique which expands the applicability of mass spectrometry to highly polar and/or thermally labile compounds and therefore has found numerous analytical applications in biochemical, medical and environmental research Although originally designed and developed for ionization of organic compounds of low volatility the technique has unexpectedly proved to be a powerful tool in the analysis of a large number of metals. 

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Carlson RW, Hauri EH (2001) Extending the ° Pd- ° Ag chronometer to low Pd/Ag meteorites with multicollector plasma-ionization mass spectrometry. Geochim Cosmochim Acta 65 1839-1848 Clayton, RN, Onuma N, Mayeda TK (1976) Distribution of the presolar component in Allende and other carbonaceous chondrites. Earth Planet Sci Lett 30 10-18 Compston W, Oversby VM (1969) Lead isotopic analysis using a double spike. J Geophys Res 74 4338-4348 Criss RE (1999) Principles of Stable Isotope Distribution. University Press, Oxford... 

Kwon JY, Moini M. 2001. Analysis of underivatized amino acid mixtures using high performance liquid chromatogra-phy/dual oscillating nebulizer atmospheric pressure micro-wave induced plasma ionization-mass spectrometry. J Am Soc Mass Spectrom 12 117. 

Carlson, R. W. and Hauri, E. H. (2001) Extending the 107Pd-107Ag chronometer to low Pd/Ag meteorites with multicollector plasma-ionization mass spectrometry. Geochimica et Cosmochimica Acta, 65, 1839—1848. 

Elements are incorporated into teeth from the diet or by inhalation. The figure shows trace element profiles measured by laser ablation—plasma ionization-mass spectrometry of the dentine of teeth from a modem person and one who lived in Scandinavia about a.d. 1800. The contrast is striking. The old tooth contains significant amounts of tin and bismuth, which are nearly absent in the modern tooth. The old tooth contains more lead and antimony than the modem tooth. Tin and lead are constituents of pewter, which was used for cooking vessels and utensils. Bismuth and antimony also might come from pewter. 

The technique based on laser-induced breakdown coupled to mass detection, which should thus be designated LIB-MS, is better known as laser plasma ionization mass spectrometry (LI-MS). The earliest uses of the laser-mass spectrometry couple were reported in the late 1960s. Early work included the vaporization of graphite and coal for classifying coals, elemental analyses in metals, isotope ratio measurements and pyrolysis [192]. Later work extended these methods to biological samples, the development of the laser microprobe mass spectrometer, the formation of molecular ions from non-voIatile organic salts and the many multi-photon techniques designed for (mainly) molecular analysis [192]. 

Stewart I. I., Guevremont R. and Sturgeon R. E. (1999) The use of a sampler-skimmer interface for ion sampling in furnace atomization plasma ionization mass spectrometry, Anal Chem 71 5146-5156. 

The main purpose of the detector in a field-flow fractionation (FFF) system is to quantitatively determine particle number, volume, or mass concentrations in the FFF size-sorted fractions. Consequently, a number, volume, or mass dependent size distribution of the sample can be derived from detection systems applied to FFF [e.g., (UV-Vis) fluorescence, refractive index, inductively coupled plasma ionization mass spectrometry (ICPMS)]. Further, on-line light scattering detectors can provide additional size and molecular weight distributions of the sample. 

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. 

GC/MS has been employed by Demeter et al. (1978) to quantitatively detect low-ppb levels of a- and P-endosulfan in human serum, urine, and liver. This technique could not separate a- and P-isomers, and limited sensitivity confined its use to toxicological analysis following exposures to high levels of endosulfan. More recently, Le Bel and Williams (1986) and Williams et al. (1988) employed GC/MS to confirm qualitatively the presence of a-endosulfan in adipose tissue previously analyzed quantitatively by GC/ECD. These studies indicate that GC/MS is not as sensitive as GC/ECD. Mariani et al. (1995) have used GC in conjunction with negative ion chemical ionization mass spectrometry to determine alpha- and beta-endosulfan in plasma and brain samples with limits of detection reported to be 5 ppb in each matrix. Details of commonly used analytical methods for several types of biological media are presented in Table 6-1. 

Pickett DA, Murrell MT, Williams RW (1994) Determination of femtogram quantities of protactinium in geologic samples by thermal ionization mass spectrometry. Anal Chem 66 1044-1049 Pietruszka AJ, Carlson RW, Hauri EH (2002) Precise and accurate measurement of Ra- °Th- U disequilibria in volcanic rocks using plasma ionization multicollector mass spectrometry. Chem Geol 188 171-191... 

Anacardio, R., Cantalini, M.G., De Angelis, F., and Gentile, M., Quantification of S-carboxymethyl-(R)-cysteine in human plasma by high-performance ion-exchange liquid chromatography/atmospheric pressure ionization mass spectrometry, /. Mass Spectrom., 32, 388, 1997. 

McLoughlin, D.A., Olah, T.V., and Gilbert, J.D. 1997. A direct technique for the simultaneous determination of 10 drug candidates in plasma by liquid chromatography/atmospheric pressure chemical ionization mass spectrometry interfaced to a Prospekt solid-phase extraction system. J. Pharm. Biomed. Anal. 15 1893. 

Ma, Y. et al. 2007. Determination and pharmacokinetic study of amlodipine in human plasma by ultra performance liquid chromatography-electrospray ionization mass spectrometry. J Pharm Biomed Anal. 43 1540. 

R. Doucelance and G. Manhes. Reevaluation of Precise Lead Isotope Measurements by Thermal Ionization Mass Spectrometry Comparison with Determinations by Plasma Source Mass Spectrometry. Chem. Geol, 176(2001) 361-377. 

Spivack AJ, Edmond JM (1986) Determination of horon isotope ratios hy thermal ionization mass spectrometry of the dicesium metaborate cation. Anal Chem 58 31-35 Tanner SD, Cousins LM, Douglass DJ (1994) Reduction of space charge effects using a three-aperture gas dynamic vacuum interface for inductively coupled plasma mass spectrometry. Appl Spectrosc 48 1367-1372... 

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). 

Kim Y-S, Zhang H, Kim H-Y. 2000. Profiling neurosteroids in cerebrospinal fluids and plasma by gas chromatography/ electron capture negative chemical ionization mass spectrometry. Anal Biochem 277 187. 

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