Thin-layer chromatography, fields

The on-line principle has also been extended into the field of detection (Fig. 8). Thus, it is now possible to record FTIR [27-31] and Raman spectra in situ [32, 33], and there have been considerable advances in the on-line coupling of thin-layer chromatography with mass spectrometry. Here it has been, above all, the research groups of Wilson [34-36] and Busch [37-40] that have made the necessary instrumental and methodological advances, so that TLC must no longer be viewed as merely a clean-up method. Rather it forms the essential central point for all these on-line coupling techniques. 

The currently most important fields of application of thin-layer chromatography be seen in Fig. 1. The proportion of publications in the fields of pharmacy and vironmental analysis has increased over that in previous years. There has also beer appreciable increase in the fields of clinical and forensic chemistry and in biochemis... 

Fig. 1 Fields of application of thin-layer chromatography (TLC/HPTLC) during the pei 1988-1991.

Payne [30] carried out a field investigation of benzopyrene hydrolysate induction as monitor for marine petroleum pollution. Isaaq et al. [31] isolated stable mutagenic ultraviolet photodecomposition products of benzo(a)pyrene by thin-layer chromatography. 

Key words Explosives analysis, field test kit, propellant stabilizer analysis, thin-layer chromatography, defense clean-up, environmental field test kit... 

A host of analytical techniques, including thin-layer chromatography and NMR spectroscopy, are available to the researcher in the field of solution-phase organic chemistry. These methods enable rapid assessment of the progress of the reaction in question. 

Schulten, H.-R., and Soldati, F. (1981). Identification of ginsenosides from Panax ginseng in fractions obtained by high-performance liquid chromatography by field desorption mass spectrometry, multiple internal reflection infrared spectroscopy and thin layer chromatography. J. Chromatogr. 212, 37-i9. 

Analysis of On-Site Wastewaters for Pesticides by Thin-Layer Chromatography. A field method to identify qualitatively and semi-quantitatively the pesticide constituents of a pesticide-laden wastewater was developed. The field method was developed using thin-layer chromatography (TLC). TLC gives a presumptive test for the presence of specific pesticides and within 30 minutes an estimate of their concentrations. TLC may also reveal the presence of unknown substances. The field application of thin-layer chromatography requires a skilled chemist, but no expensive equipment. The following protocol describes the on-site use of TLC. 

In both of these field tests, the application of thin-layer chromatography was essential for characterizing the pesticides in the water and in monitoring the progress of their removal by the carbon filtration system. 

Sulfur compounds are abundant in petroleum, but one of the major gaps in the analytical chain between source and end product lies in this field. Thin layer chromatography is useful for isolating and identifying... 

Other techniques that have been used to determine polycyclic aromatic hydrocarbons in soil extracts include ELISA field screening [86], micellar elec-tr okinetic capillary chromatography [ 87], supersonic jet laser-induced fluorescence [88,89], fluorescence quenching [90], thermal desorption gas chromatography-mass spectrometry [81,90,100], microwave-assisted extraction [91], thermal desorption [92], immunochemical methods [93,94], electrophoresis [96], thin layer chromatography [95], and pyrolysis gas chromatography [35]. 

Identification of decomposition products and metabolic products is most conveniently done by their isolation using thin layer chromatography and identification by use of field desorption mass spectrometry. 

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