Chromatography qualitative analysis

W. Jennings and T. ShS o2im.o. o, Qualitative Analysis of Flavor andFragrance Volatiles by Glass Capillay Gas Chromatography, Academic Press, Inc., New York, 1980 also iacludes retention iadexes and mass spectral data. 

Multidimensional gas chromatography has also been used in the qualitative analysis of contaminated environmental extracts by using spectral detection techniques Such as infrared (IR) spectroscopy and mass spectrometry (MS) (20). These techniques produce the most reliable identification only when they are dealing with pure substances this means that the chromatographic process should avoid overlapping of the peaks. 

Dear, G.J., Fraser, I.J., Patel, D.K., Long, J., and Pleasance, S., Use of liquid chromatography-tandem mass spectrometry for the quantitative and qualitative analysis of an antipsychotic agent and its metabolites in human plasma and urine, /. Chromatogr. A, 794, 27, 1998. 

Mass spectrometry offers a special advantage over other detection schemes for instrumental chromatography because the mass spectra of the mixture components are acquired, providing a very powerful qualitative analysis tool for these components. 

Figure 11.22 represents a paper electrophoresis apparatus. The soaked cellulose sheet is sandwiched between two horizontal glass plates with the ends dipped into vessels containing more electrolyte solution. The electrodes are also dipped into these vessels, as shown. The sample is spotted in the center of the sheet, and the oppositely charged ions then have room to migrate in opposite directions on the sheet. Qualitative analysis is performed much as with paper chromatography, by comparing the distances the... 

We discussed the fundamentals of mass spectrometry in Chapter 10 and infrared spectrometry in Chapter 8. The quadrupole mass spectrometer and the Fourier transform infrared spectrometer have been adapted to and used with GC equipment as detectors with great success. Gas chromatography-mass spectrometry (GC-MS) and gas chromatography-infrared spectrometry (GC-IR) are very powerful tools for qualitative analysis in GC because not only do they give retention time information, but, due to their inherent speed, they are also able to measure and record the mass spectrum or infrared (IR) spectrum of the individual sample components as they elute from the GC column. It is like taking a photograph of each component as it elutes. See Figure 12.14. Coupled with the computer banks of mass and IR spectra, a component s identity is an easy chore for such a detector. It seems the only real... 

Gas-liquid chromatography is a very useful technique in lipid analysis, particularly for the separation of very similar compounds within classes. Because of the wide variations in structure and properties between classes it is not usually possible to resolve members of different classes on the same column. GLC is useful for both quantitative and qualitative analysis and also in the investigation of lipid structure. 

The prediction of retention times in a given eluent from log P has been proposed for aromatic hydrocarbons.19 The log A values of phenols21 and nitrogen-containing compounds22 were also related to their logP, and the calculated log P was used for the qualitative analysis of urinary aromatic acids, i.e. for the identification of metabolites in urine from the differences of log P in reversed-phase liquid chromatography.23,24... 

The qualitative analysis of retention behaviour in liquid chromatography has now become possible. Quantitative retention-prediction is, however, still difficult the prediction of retention time and the optimization of separation conditions based on physicochemical properties have not yet been completely successful. One reason is the lack of an ideal stationary phase material. The stationary phase material has to be stable as part of an instrument, and this is very difficult to achieve in normal-phase liquid chromatography because the moisture in organic solvents ages the silica gel. 

Mohn T, Cutting B, Ernst B, Hamburger M (2007) Extraction and analysis of intact glucosinolates-a validated pressurized liquid extraction/liquid chromatography-mass spectrometry protocol for Isatis tinctoria, and qualitative analysis of other cruciferous plants. J Chromatogr 1166 142-151... 

Jennings, W. G. Shibamoto, T. Qualitative Analysis of Flavor and Fragrance Volatiles by Glass Capillary Gas Chromatography Academic Press New York, NY, 1980. 

Qualitative analysis by gas chromatography (GC) in the classical sense involves the comparison of retention data of an unknown sample with that of a known sample. The alternate approach involves combination and comparison of gas chromatographic data with data from other instrumental and chemical methods. 

Ito, Y., W.D. Conway, and Y. Ato, Editors High-Speed Countercurrent Chromatography (Chemical Analysis. Vol. 132) John Wiley Sons, New York, NY, 1995. Kenneth, W.W., R,E Davis, and PM. Larry General Chemistry with Qualitative Analysis, 6th Edition, Saunders College Publishing, Philadelphia, PA, 1999. Kohlmann, F. Electrical Conductivity Measurements, in Process/lndustrial Instruments Controls Handbook, D.M. Considine, Editor, 4th Edition, McGraw-Hill, New York, NY, 1993. 

Basic Protocol 1 Qualitative Analysis of Citrus Oils by Gas Chromatography Basic Protocol 2 Quantitative Analysis of Citrus Compounds by Gas Gl.5.2... 

As already mentioned, it is the volatile constituents that serve to identify fruit type and variety. Broadly speaking, qualitative analysis will identify the principal substances present in the volatiles fraction as representative of a particular fruit type, but it is the relative proportions of these substances that will reflect the variety. Alcohols, volatile acids, esters, carbonyl compounds, and low-boiling hydrocarbons are the principal groups represented. Analysis by GC-MS (gas chromatography coupled with mass spectroscopy) can be used to provide quantification and identification of the various constituents. 

J.O. Doali A.A. Juhasz, Application of High-Performance Liquid Chromatography to the Qualitative Analysis of Compounds of Propellant and Explosives Interest , JChromatogrSci 12 (1), 51 -56 (1974) 92) F.T. Sweeney P.W.D. 

K. A. Krock and C. L. Wilkins, Qualitative analysis of contaminated environmental extracts by multidimensional gas chromatography with infrared and mass spectral detection (MDGC-IR-MS) , pp. 167-178, copyright 1996, with permission from Elsevier Science. 

Qualitative analysis of small quantities of material (10 610 9g), particularly in conjunction with gas-liquid chromatography, HPLC and ICP. 

Table III. Examples of qualitative analysis of PGS using gas chromatography-mass spectroscopy.

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