Isotope ratio analysis

Walter, W.D. Leslie, Jr., D.M. (2009). Stable isotope ratio analysi to differentiate temporal diets of a free-ranging herbivore. Rapid Communications in Mass Spectrometry, Vol. 23, pp. 2190-2194. (http //dx.doi.org/10.1002/rcm.4135)... 

Barrie, A., Bricout, J. and Koziet, J. (1984) Gas chromatography stable isotope ratio analysis at natural abundance levels. Biomedical Mass Spectrometry 11, 439 447. 

Bilke, S. and Mosandl, A. (2002) Measurements by gas chromatography/pyrolysis/mass spectrometry fundamental conditions in 2H/1H isotope ratio analysis. Rapid Communications in... 

Oxygen isotope ratio analysis provides a powerful tool for the study of water/rock interaction. The geochemical effect of such an interaction between water and rock or mineral is a shift of the oxygen isotope ratios of the rock and/or the water away from their initial values, given that their compositions are not in equilibrium. 

Brand W (2002) Mass spectrometer hardware for analyzing stable isotope ratios. In P de Groot (ed.) Handbook of stable isotope analytical techniques. Elsevier, Amsterdam Brandriss ME, O Neil JR, Edlund MB, Stoermer EF (1998) Oxygen isotope fractionation between diatomaceous silica and water. Geochim Cosmochim Acta 62 1119-1125 Bremner JM, Keeney DR (1966) Determination and isotope ratio analysis of different forms of nitrogen in soils. III. Soil Sci Soc Am Proc 30 577-582 Brenninkmeijer CAM (1993) Measurement of the abundance of CO in the atmosphere and the and 0/ 0 ratio of atmospheric CO with applications in New Zealand and Australia. J Geophys Res 98 10595-10614... 

The best precision is obtained for isotope ratios near unity (unless the element to be determined is near the detection limit, when the ratio of spike isotope to natural isotope should be between 3 and 10) so that noise contributes only to the uncertainty of natural isotope measurement. Errors also become large when the isotope ratio in the spiked sample approaches the ratio of the isotopes in the spike (overspiking), or the ratio of the isotopes in the sample (underspiking), the two situations being illustrated in Fig. 5.11. The accuracy and precision of the isotope dilution analysis ultimately depend on the accuracy and precision of the isotope ratio measurement, so all the precautions that apply to isotope ratio analysis also apply in this case. 

Isotope ratio analysis, 131-134 abundance, 131 correction factor, 131 detector dead time, 132-133 mass bias, 131. 132(f) precision of, 133... 

LA-TOF-ICP-MS may be a useful tool for distinguishing different sources of lead found in low-lead, alkaline-based and lead-based glazes from Mesopotamia. Even with the limitations of the present study, lead-isotope ratios determined by TOF-ICP-MS indicate that multiple ore sources were utilized by makers of Islamic lead-glazed pottery. With the further refinements of Dudgeon et al. (this volume), LA-TOF-ICP-MS promises to be a rapid, cost-effective approach to lead-isotope ratio analysis of glazed pottery. 

Much progress has also been made in the development of methods for authenticity control of flavor compounds, such as chiral separations or isotope ratio analysis. However, a comprehensive discussion of this subject would have gone beyond the limits of this chapter. The interested reader is, therefore, referred to some recent articles published in this field [109-111],... 

Cotte, J. F., Casabianca, H., Lheritier,J., Perrucchietti, C., Sanglar, C., Waton, FI., and Grenier-Laustalot, M. F. (2007). Study and validity of 13C stable carbon isotope ratio analysis by mass spectrometry and 2H site-specific natural isotopic fractionation by nuclear magnetic resonance isotopic measurements to characterize and control the authenticity of honey. Anal. Chim. Acta 582,125-136. 

Giraudon, S., Danzart, M., and Merle, M. H. (2000). Deuterium nuclear magnetic resonance spectroscopy and stable carbon isotope ratio analysis/mass spectrometry of certain monofloral honeys.. AOAC Int. 83,1401-1409. 

Mass Spectral Techniques. Samples for isotope ratio analysis are typically converted to sulfates or sulfides, then to S02(g) for analysis on a mass spectrometer (MS). The precision of the S02 measurement is commonly reported as 0.1 to 0.2 0/00 (16.241. yet systematic errors of 1 0/00 or larger may result from 1) memory effects due to adsorption of S02 on the walls of the MS, and 2) secondary isotope effects due to the existence of two stable isotopes of oxygen, 160 and lsO (251. Both of these errors can be eliminated by using SF6 rather than S02 as the analyte in the MS (25.261. However, existing sulfur fluorination procedures are relatively dangerous and tedious, making the SF6 method less desirable as a routine environmental technique (261. 

Emitters that have ions produced in situ are by far the largest group of known ion emitters. They are much more difficult to scale in intensity than prefonned ion emitters. In general, methods have been developed that give stable and reproducible ion beams with sufficient intensity to provide an isotope ratio analysis for the particular element to be analyzed. As stated earlier, it is not necessary to understand the mechanistics of ion emission to use these ion emitters for isotope ratio analysis as long as the ion beams are sufficiently stable with adequate intensity. There... 

Thirlwall, M.F., and Walder, A.J. (1995) In situ hafnium isotope ratio analysis of zircon by inductively coupled plasma multiple collector mass spectrometry. Chem. Geol. 122, 241-247. 

Matrix effects (termed instrumental mass bias) also present problems in isotope ratio analysis as the measured isotope ratio is almost always light isotope enriched relative to the accepted ratio, and the degree of this enrichment depends on the matrix composition. Although mass bias variations between different mineral compositions are relatively minor for most elements (a few percentage points at most), the high accuracy required in isotope analysis (often 1% or better) demands careful calibration. For isotope ratio measurements in essentially isochemical... 

Cumin essential oil can be adulterated with synthetic cumin aldehyde, which is difficult to detect, though methods such as stable isotope ratio analysis and selective ion monitoring help in detecting adulteration of this kind (Amin, 2000). 

Lamprecht, G., Pichlmayer, F. and Schmid, E.R. (1994) Determination of the authenticity of vanilla extracts by stable isotope ratio analysis and component analysis by HPLC. Journal of Agricultural and Food Chemistry 42, 1722-1 72 7. 

Lee, K., Gillatt, P. and Rossell, J.B. (1993) Authenticity of edible vegetable oils and fats, Part XX determination of maize oil purity by stable carbon isotope ratio analysis (SCIRA). Leatherhead Food RA Research Reports No. 719. Leatherhead Food RA, UK. 

TABLE 5.1. An Overview of the Use of Heavy Isotopic Ratio Analysis in Studies to Determine the Geographical Origin of Foods... 

Schmidt, O., Quilter, J.M., Bahar, B., Moloney, A.P., Scrimgeour, C.M., Begley, I.S., Monahan, F.J. Inferring the origin and dietary history of heef from C, N and S stable isotope ratio analysis. Food Chem. 91, 545-549 (2005)... 

Werner, R.A. Brand, W.A. (2001) Referencing strategies and techniques in stable isotope ratio analysis. Rapid Communications in Mass Spectrometry 15, 501-519. 

Stable Isotope Ratio Analysis in Quality Control of Flavourings... 

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