Sensitivity analysis spectrometry

Reliable analytical methods are available for determination of many volatile nitrosamines at concentrations of 0.1 to 10 ppb in a variety of environmental and biological samples. Most methods employ distillation, extraction, an optional cleanup step, concentration, and final separation by gas chromatography (GC). Use of the highly specific Thermal Energy Analyzer (TEA) as a GC detector affords simplification of sample handling and cleanup without sacrifice of selectivity or sensitivity. Mass spectrometry (MS) is usually employed to confirm the identity of nitrosamines. Utilization of the mass spectrometer s capability to provide quantitative data affords additional confirmatory evidence and quantitative confirmation should be a required criterion of environmental sample analysis. Artifactual formation of nitrosamines continues to be a problem, especially at low levels (0.1 to 1 ppb), and precautions must be taken, such as addition of sulfamic acid or other nitrosation inhibitors. The efficacy of measures for prevention of artifactual nitrosamine formation should be evaluated in each type of sample examined. 

C. Tuniz, Accelerator mass spectrometry ultra sensitive analysis for global science, Rad. Phys. Chem. 61, 317 322 (2001). 

Nedelkov, D., Rasooly, A., and Nelson, R. W. (2000). Multitoxin biosensor-mass spectrometry analysis A new approach for rapid, real-time, sensitive analysis of staphylococcal toxins in food. Int.. Food Microbiol. 60,1-13. 

In experiments where a higher degree of sensitivity and selectivity is required, fluorescence and mass-selective detectors have been applied. Picomole limits of detection offered by fluorescence makes it ideal for routine analysis requiring high sensitivity. Mass spectrometry has also proven to be both a sensitive and efficient way to identify numerous chlorophyll derivatives (unitf4.s). van Breemen et al. (1991) utilized both fast atom bombardment (FAB) and tandem mass spectrometry (MS/MS) for the structural characterization and mass determination of numerous deriva-... 

Emmett, M. R. Caprioli, R. M. 1994. Micro-electrospray mass spectrometry ultra-high-sensitivity analysis of peptides and proteins. J. Am. Soc. Mass Spectrom., 5,605-613. 

Figeys, D. Aebersold, R. 1998. High sensitivity analysis of proteins and peptides by capillary electrophoresis-tandem mass spectrometry recent developments in technology and applications. Electrophoresis, 19, 885-892. 

Perkins, R. W., and D. E. Robertson Selective and Sensitive Analysis of Activation Products by Multidimensional Gamma-Ray Spectrometry. Modern Trends in Activation Analysis-Proceedings of the 1965 International Conference in College Station, Texas, April, 1965. A and M College of Texas, College Station, Texas, pp. 48—57 (1965). 

Bahr, U., Pfenninger, A., Karas, M. and Stahl, B. (1997) High sensitivity analysis of neutral underivatized oligosaccharides by nanoelectrospray mass spectrometry. Anal. Chem., 69 (22), 4530-5. 

Arsenic is readily detected the Marsh test was devised in 1836 and was used for over a hundred years. More sophisticated and very sensitive methods are now available, using X-ray analysis or a technique known as mass spectrometry which detects the arsenic atoms. Even before the Marsh test a careful scientific process of experiment would sometimes be successful, as demonstrated by the doctor in the case of Mary Blandy in 1752 (see case notes p. 223). Arsenic remains in tissues of the body for a long time, hence analysis of Napoleon s hair was possible long after his death (see case notes p. 222). The sensitive analysis of hair and nails from the body of American president Zachary Taylor, exhumed in 1991, also established that he was not poisoned in 1850. 

Tuniz, C., Baird, J.R., Fink, D. Herzog, G.F. (1998) Accelerator Mass Spectrometry, Ultra Sensitive Analysis for Global Science. Boca Raton, FL CRC Press. 

SC Flenderson, SJ Valentine, AE Counterman, DE Clemmer. ESI/ion trap/ion mobility/time-of-flight mass spectrometry for rapid and sensitive analysis of biomolecular mixtures. Anal Chem 71 291—301, 1999. 

Mass spectrometry (MS) possesses the unique abihty to identify separated compounds and is now used routinely with gas and liquid chromatography. This selective and highly sensitive detection mode is also compatible with capillary electrophoresis and provides a powerful combination for performing rapid, efficient and sensitive analysis. 

Another current trend that is well underway is the use of more specific analytical instrumentation that allows less extensive sample preparation. The development of mass spectrometric techniques, particularly tandem MS linked to a HPLC or flow injection system, has allowed the specific and sensitive analysis of simple extracts of biological samples (68,70-72). A similar HPLC with UV detection would require significantly more extensive sample preparation effort and, importantly, more method development time. Currently, the bulk of the HPLC-MS efforts have been applied to the analysis of drugs and metabolites in biological samples. Kristiansen et al. (73) have also applied flow-injection tandem mass spectrometry to measure sulfonamide antibiotics in meat and blood using a very simple ethyl acetate extraction step. This important technique will surely find many more applications in the future. 

The separation of yttrium from the lanthanides is performed by selective oxidation, reduction, fractionated crystallization, or precipitation, ion-exchange and liquid-liquid extraction. Methods for determination include arc spectrography, flame photometry and atomic absorption spectrometry with the nitrous oxide acetylene flame. The latter method improved the detection limits of yttrium in the air, rocks and other components of the natural environment (Deuber and Heim 1991 Welz and Sperling 1999).Other analytical methods useful for sensitive monitoring of trace amounts of yttrium are X-ray emission spectroscopy, mass spectrometry and neutron activation analysis (NAA) the latter method utilizes the large thermal neutron cross-section of yttrium. For high-sensitivity analysis of yttrium, inductively coupled plasma atomic emission spectroscopy (ICP-AES) is especially recommended for solid samples, and inductively coupled plasma mass spectroscopy (ICP-MS) for liquid samples (Reiman and Caritat 1998). 

All of these fields have requirements for sensitive analysis of radionuclides. In general, mass spectrometry is used for measuring long-lived radionuclides at low abundances, where radiation-counting techniques provide insufficient sensitivity. Modern mass spectrometers can detect individual atoms, which translates into... 

B.S. Dumesh, VP. Kostromin F.S. Rusin and L.A. Surin, Highly Sensitive MMW Spectrometry Based on an Orotron, Meas. Sci. Technol., 1992, 3, 873-878 B.S. Dumesh, VD. Gorbatenkov, VG. Koloshnikov, VA. Panfilov and L.A. Surin, Application of Highly Sensitive MMW Cavity Spectrometer Based on an Orotron for Gas Analysis, Spectrochim. Acta, Part A, 1997, 55, 835-844. 

FIGURE 9.3 Contourplots of nested drift time (bottom) and flight time (left) data for amix-ture of peptide ions that were formed by direct electrospray of a tryptic digest of cytochrome c. Projection of the data along the bottom and left axes shows ion mobility and time-of-flight dis-tribntions, respectively. (Taken from Henderson et al., ESI/ion trap/ion mobility/time-of-flight mass spectrometry for rapid and sensitive analysis of biomolecnlar mixtures, Anal. Chem. 1999, 71, 291. With permission.)... 

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