Qualitative analysis thin-layer chromatograph

Modem planar chromatography is suitable not only for qualitative and quantitative analysis but also for preparative purposes. The separation efficiency of a thin-layer chromatographic system is independent of this intended purpose and is mainly determined by the quahty of the stationary phase, that is to say, by the applied coated layer. Therefore, progress in modem planar chromatography can be attributed not only to the development of the efficiency of the instmments but also to a large extent to the availability of high-quahty precoated layers. And today, as in the past, bulk sorbents for self production, especially of preparative layer chromatography (PLC) layers, are widely used. 

G. Musumarra, G. Scarlata, G. Cirma, G. Romano, S. Palazzo, S. dementi, and G. Ginlietti, Qualitative organic analysis, Analysis of standarized thin-layer chromatographic data in four eluent systems, J. Chromatogr., 297 249 (1984). 

Methods of Analysis of Pesticides. The extracted residue obtained after isolation from tissues and other biological materials is subjected to qualitative and quantitative determination of the pesticides. Sometimes, the amount of material available is so small that the colorimetric and other allied methods cannot be successfully applied as some of the residue is likely to be lost during the purification technique. Furthermore, these purification techniques required for spectrophotometry, colorimetry, and other sophisticated instrumental methods are appreciably time consuming. Therefore, other techniques were sought for the quantitative determination of pesticides. Thin layer chromatographic (TLC) techniques were found to be most suitable for toxicological analysis of pesticides. Randerath(16j stated that... 

Silica gel is the most extensively used adsorbent in thin layer chromatography because it leads to excellent, uncomplicated separations. It can be successfully employed for both qualitative and quantitative thin layer chromatographic analyses. It is usually used as a stationary phase in separations and analysis of alkaloids, various organic acids (especially amino acids and their derivatives), steroids, lipids, vitamins, plant pigments, pesticides, drugs, carbohydrates, phenolic substances, etc. 

Solute identification means qualitative analysis. Various methods are used today to identify a separated substance on a thin-layer chromatographic plate. Of all chromatographic methods, thin-layer chromatography (TLC) provides a unique simultaneous separation of up to 70 samples on the same plate therefore the reproducibility of the experimental conditions is not an issue because the experimental conditions are the same for all samples. This, together with the advantage of separating compounds with very different polarity and the possibility of using different detection methods for the same spot or for adjacent spots on the same plate, is the power of TLC. 

Of the various analytical methods described, the ISO recommended a thin-layer chromatographic technique [35] for qualitative analysis of saffron, whereas quantitative HPLC methods have been described for the analysis of commercial saffron products [36], Other reports on chemical analysis of saffron constituents including combination of the reported methods, crystal structure analysis, Fourier Transform-Inffa Red (FT-IR) and Raman analysis are worth mentioned [37-40]. Very interesting is also the review article by Rios et al [41] on chemical analysis of saffron. 

Le Fevre, J.W. Gublo, E.J. Botting, C. Wall, R. Nigro, A. Pham, M.L.T. Ganci, G. Qualitative reversed-phase thin-layer chromatographic analysis of the stereochemistry of D- and L-a-amino acids in small peptides. J. Planar Chromatogr. Mod. TLC 2000,13,160-165. 

The thin layer column, also called the analytical column, is ideal for all types of quantitative and qualitative analysis, because they provide the best possible resolution in comparison to other gas chromatographic columns. A thin layer... 

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