Identification of species

Hardy, A.R. (1990). Estimating exposure The identification of species at risk and routes of exposure. In L. Somerville and C.H. Walker (Eds.) Pesticide Effects on Terrestrial Wildlife, 81-98, London Taylor Francis. 

R. Goodacre, D.B. Kell and G. Bianchi, Rapid identification of species using pyrolysis mass spectrometry and artificial neural networks of propionibacterium acnes isolated from dogs. J. Appl. Bacteriol., 76 (1994) 124-134. 

There have been a number of attempts to achieve this objective, but so far the challenge has not been fully met. This Chapter will examine some of the conventional approaches and then go on to consider how recent developments in the use of the Polymerase Chain Reaction (PCR) with DNA for the identification of species and individual organisms by DNA analysis, sometimes known as DNA Fingerprinting", have identified a yet unrealized need for a new dimension of certified reference materials. 

Loy, T. H. (1983), Prehistoric blood residues Detection on tool surfaces and identification of species of origin, Science 220, 1269-1271. 

Freeman, R. Goodacre, R. Sisson, P. R. Magee, J. G. Ward, A. C. Lightfoot, N. F. Rapid identification of species within the Mycobacterium tuberculosis complex by artificial neural network analysis of pyrolysis mass spectra. J. Med. Microbiol. 1994, 40,170-173. 

Occasionally, typical pattern can be observed which can be formed according to special rules like multiplets in ESR-, NMR-, and OES spectroscopy or isotopic ratios in MS (molecular peak pattern). There can also be randomly formed pattern within such spectra, being rich in signals like OES (e.g. the known sodium doublet (Na-D) 589.6 and 589.0 nm, and the magnesium quintet 277.67, 277.83, 277.98, 278.14, and 278.30 nm). The identification of species is always made easier when pattern - whatever type - can be compared instead of a number of signals that are irregularly arranged. 

Electron paramagnetic resonance (epr) spectroscopic methods are used for the detection and identification of species that have a nett electronic spin radicals, radical ions, etc. It is extremely sensitive, capable of detecting species down to concentration levels of 1 x 10 12 moles dm "3, and produces spectra that are distinctive and generally easily interpreted. Consequently, the technique has found extensive application in electrochemistry since the late 1950s. In order to understand epr, it may be helpful to review some fundamental concepts. 

Numerous SERS studies of adsorbed molecules have appeared in the literature. Obviously, it is a useful method for the identification of species at the interface, and its inherent surface sensitivity is an attractive feature. In this context it should be noted that the adsorption of a molecule can change the selection rules for Raman scattering, and modes that are Raman inactive in the isolated molecule may show up in SERS. 

These equilibria have been studied by various methods of which potentiometry and 51V NMR spectroscopy proved to be particularly useful for the identification of species and the determination of stability constants (8-10,13-16,18,20,22,24). Values obtained for stability constants by different research groups under the same conditions usually show good agreement, e.g., for 0.60 M NaCl medium (Table II). In some cases so-called Bronsted (or mixed) constants (25) are... 

The fluorescence spectrum of a compound may be used in some cases for the identification of species, especially when the spectrum exhibits vibronic bands (e.g. in the case of aromatic hydrocarbons), but the spectra of most fluorescent probes (in the condensed phase) exhibit broad bands. 

Voordouw, G., Niviere, V, Ferris, F. G., Fedorak, P. M. and Westlake, D. W. (1990) Distribution of hydrogenase genes in Desulfovibrio spp. and their use in identification of species from oil fields environment. Appl. Environ. Microbiol., 56, 3748-54. 

Most of the spectroscopic investigations discussed above were carried out on well-defined metallocene systems, either isolated species or those generated from a well-defined metallocene alkyl precursor activated with one equivalent of a borane or borate activator. Most practical polymerisation catalysts, on the other hand, include a scavenger, usually an aluminum alkyl, and may contain ill-defined activators such as methylaluminoxane (MAO), usually at high MAO/Zr ratios. Such systems are less amenable to quantitative studies nevertheless, the identifications of species such as those depicted in Schemes 8.5-8.8 has enabled similar compounds to be identified in more complex mixtures. An idea of the possible mode of action... 

A Finnigan Ion Trap Detector (ITD), a small mass spectrometer for capillary chromatography, is the third detector interfaced with the gas chromatograph. The control of the ITD, the data collection, and the identification of species, by a library... 

Identification of Species in SEC Fractions of Wyodak Recycle Solvent... 

Ozawa, T. et al.. Identification of species-specific flavone glucosides useful as taxonomic markers in the genus Pyrus, Biosci. Biotechnol. Biochem., 59, 2244, 1995. 

Although the emphasis in this article has been on the discussion of toihniques and methods that can be used in the laboratory for the identification of species, increasing importance is being attached to computer simulation of trace element speciation. The reason for this increased interest could be attributed in part to the availability of relevant experimental data which could be used in developing the required models. However, computer simulation comes into its own when the species are so imstable that separation techniques cannot be applied and/or the detection systems do not have the required sensitivity. 

An interpretation of the results and a hypothesis on potential intermediates was difficult at this stage, since no defined complexes could be obtained. The first identification of species present in solution during the catalysis of the Diels-Alder reaction was achieved in a collaboration between our group and three physical chemists, Bertagnolli, Gescheidt, and Schweiger [64]. Using various techniques... 

Identification of Species Involving Electrochemically Depositable Metals... 

Identification of Species Using Reductive/Oxidative Dissolution Process... 

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