With Fourier transform infrared spectrometry

Despite its inherent analytical difficulties, gas chromatography on capillary columns in combination with sensitive and specific mass spectrometry has been widely used for separation of these analytes. Typical examples of such applications are those interfacing gas chromatography with mass spectrometry via electron impact (470, 484, 480, 489), chemical ionization (481, 478, 483, 473), or both interfaces (474, 475, 487, 488). Apart from mass spectrometry, Fourier transform infrared spectrometry has also been suggested as an alternative very useful identification tool in the area of the -agonist analysis. Capillary gas chromatography with Fourier transform infrared spectrometry was successfully employed to monitor clenbuterol, mabuterol, and salbutamol residues in bovine liver and urine (471). 

Somsen, G.W. Rozendom, E.J.E. Gooijer, C. Velthorst, N.H. Brinkman, U.A.Th. Polymer analysis by column liquid chromatography coupled semi-on-line with Fourier transform infrared spectrometry. Analyst 1996, 121, 1069-1074. 

Lacroix B, Huvenne JP and Deveaux M (1989) Gas chromatography with Fourier transform infrared spectrometry for biomedical applications./o r a/ of Chromatography 492 109-136. 

Table 5.7 Theoretically predicted polypeptides from the trypsin digestion of S-lacto-globulin (/3LG) . Reprinted from J. Chromatogr., A, 763, Turula, V. E., Bishop, R. T., Ricker, R. D. and de Haseth, J. A., Complete structure elucidation of a globular protein by particle beam liquid chromatography-Fourier transform infrared spectrometry and electrospray liquid chromatography-mass spectrometry - Sequence and conformation of /3-lactoglobulin , 91-103, Copyright (1997), with permission from Elsevier Science...

Evidence of chemical interaction between the mbbers and compatibUizers was demonstrated by extracting the blends with chloroform at room temperamre and examining both soluble and insoluble fractions with Fourier transform infrared (ETIR) spectrometry. The weight of the insoluble fraction of the compatibilized melt blend was more than that in the uncompatibilized blend indicating the formation of (EP-g-MA)-g-CR due to reaction between MA and allylic chlorine of CR. The compounds containing epoxidized EPDM additive were examined by both optical and... 

With recent developments in analytical instrumentation these criteria are being increasingly fulfilled by physicochemical spectroscopic approaches, often referred to as whole-organism fingerprinting methods.910 Such methods involve the concurrent measurement of large numbers of spectral characters that together reflect the overall cell composition. Examples of the most popular methods used in the 20th century include pyrolysis mass spectrometry (PyMS),11,12 Fourier transform-infrared spectrometry (FT-IR), and UV resonance Raman spectroscopy.16,17 The PyMS technique... 

Structure elucidation of semiochemicals by modern NMR-techniques (including HPLC/NMR) is often hampered by the very small amounts of available material and problems in the isolation of pure compounds from the complex mixtures they are embedded in. Thus, the combination of gas chromatography and mass spectrometry, GC/MS, is frequently the method of choice. Determination of the molecular mass of the target compound (by chemical ionisation) and its atomic composition (by high resolution mass spectrometry) as well as a careful use of MS-Ubraries (mass spectra of beetle pheromones and their fragmentation pattern have been described [27]) and gas chromatographic retention indices will certainly facihtate the identification procedure. In addition, the combination of gas chromatography with Fourier-transform infrared spec-... 

M.T. Soderstrom, R.A. Ketola and O. Kostiainen, Identification of some nerve agents homologues and dialkyl methylphosphonates by gas chro-matography/Fourier transform infrared spectrometry, Part II Spectral search with the help of retention indices, Fresenius J. Anal. Chem., 352, 550-556 (1995). 

Romanach and de Haseth [3] have used, in CCC, a how cell for LC-FTIR (liquid chromatography-Fourier transform infrared) spectrometry. The main difflculty is the absorbance of the liquid mobile phase. This problem is exacerbated in EC by low solute-to-solvent ratios in the eluates. On the contrary, CCC leads to a high solute-to-solvent ratio so that it can be used with a very simple interface with a CCC column, without any complex solvent removal procedures. High sample loadings are possible by using the variable path length of the IR detector (from 0.025 to 1.0 mm). 

In this context, it is worthwhile to take into account that the catalytic activity of water-soluble enzymes is affected by the environment. Proteases show considerable changes in its enz)nnatic activity when trapped in water-restricted media such as reverse micelles (Peng and Luisi, 1990). Based on data obtained with Fourier transform infrared (FTIR) spectrometry and dipole surface potential in monolayers, we demonstrate that the hydration of... 

Investigations of the acidity of specific surface sites may be accomplished by studies coordinated with spectroscopic methods, such as infrared (JR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, or mass spectrometry (MS). Surface characterization with Fourier transform infrared (FTIR) spectroscopy can provide quantitative results with experimental methods that are easily performed. However, the transmission sampling techniques traditionally employed for infrared studies may introduce experimental artifacts on the analyzed surface (10,... 

Somsen, G. W., Jagt, 1., Gooijer, C., Velthorst, N. H., Brinkman, U. A. Th., and Visser, T., Identification of herbicides in river water using online trace enrichment combined with column liquid chromatography-Fourier-transform infrared spectrometry, J. Chromatogr. A, 756, 145-157, 1996. 

Miscellaneous detectors. TLC, as with other chromatographic methods, is a separation not an identification technique and thus for unambiguous identification of analytes the separated components must be examined by spectroanalytical techniques. Mass [67] and Fourier-transform infrared spectrometry [68] have both been used to good effect and considerable effort is currently being expended to develop robust methodologies and instrumentation in these areas. Instrumentation has recently been developed, for example, which elutes separated components directly onto a measured amount of potassium bromide which is then automatically pressed and introduced into an infrared spectrometer. 

The analytical technologies used In metabolomic investigations are nuclear magnetic resonance and mass spectrometry alone or in combination with liquid or gas chromatographic separation of metabolites (243). Other techniques include thin-layer chromatography, Fourier-transform infrared spectrometry, metabolite arrays, and Raman spectroscopy. 

The development of Fourier transform infrared spectrometry has been for some years at the stage where the acquisition of spectra is relatively simple, rapid and with good resolution. For identification, the method is inexpensive and can provide additional information on the nature of the chemical bonding. It is particularly suited to carbonates because of its ability to discriminate clearly between the different members. 

Fourier Transform Infrared Spectrometry has been applied to a vast array of chemical problems. The majority of these problems are beyond the scope of this review, consequently, this chapter will be limited to those techniques that have been developed or greatly advanced within the last few years. Several recent reviews have appeared that deal with the established techniques and the reader is referred to these reviews for further information. 

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