Thin layer chromatography analytical

Balogh, B. Preparative Analog to Thin Layer Chromatography. Analytic. Chem. 36, 2498 (1964). 

TLC Thin-Layer Chromatography. Analytical technique to determine composition of a sample. 

Figure 1.1 Separation of complex standard lipid mixtures on a 20 cm x 20 cm high-performance thin-layer chromatography plate using four developments. The first development was up to a distance of 5 cm above the origin in the solvent system ethyl acetate/1-propanol/chloroform/ methanol/0.025% KCl, 25 25 25 10 9 vol./vol. The second development was up to 8 cm above the origin in the solvent system toluene/ether/ethanol/acetic acid, 60 40 1 0.23 vol./vol. The third development was to the full length (9 cm) in the solvent system hexane/diethyl ether, 94 6 vol./ vol., followed by the last development to full length in hexane. The plates were freed of solvent between developments by blowing with hot air. Reproduced with permission from Yao, J. K. and Rastetter, G. M., Microanalysis of complex tissue lipids by high-performance thin-layer chromatography, Analytical Biochemistry, 150, 111-16.

Martinez-Lorenzo, M. J., Marzo, I., Naval, J. et al. (1994) Self-staining of polyunsaturated fatty acids in argentation thin-layer chromatography. Analytical Biochemistry, 220 (1), 210-12. 

Yao, J. K. and Rastetter, G. M. (1985) Microanalysis of complex tissue lipids by high-performance thin-layer chromatography. Analytical Biochemistry, 150, 111-16. 

Haddad, R., Milagre, H.M.S., Catharine, R.R., Eberlin, M.N. (2008) Easy ambient sonic-spray ionization mass spectrometry combined with thin-layer chromatography. Analytical Chemistry, 80,2744-2750. 

R. Hamilton and S. Hamilton, Thin Layer Chromatography (Analytical Chemistry by Open Learning), Wiley, New York, 1987. 

Isolation of the active constituents was done using a bioassay-guided procedure. Depending on the extract, various combinations of chromatographic methods and solvent systems were used. Basic procedures included thin layer chromatography (analytical and preparative), as well as standard column chromatography. Structures were elucidated by a combination of NMR and MS spectrometric techniques. Details of the analyses will be reported elsewhere. 

KANO H., YONEYAMA T. and KUMAZAWA K. 1981. Emission spectrometric analysis of the amino acids and amides in plant tissues separated by thin layer chromatography. Analytical Biochemistry, 67, 327-331,... 

Thin-Layer Chromatography. Chiral stationary phases have been used less extensively in tic as in high performance Hquid chromatography (hplc). This may, in large part, be due to lack of avakabiHty. The cost of many chiral selectors, as well as the accessibiHty and success of chiral additives, may have inhibited widespread commerciali2ation. Usually, nondestmctive visuali2ation of the sample spots in tic is accompHshed using iodine vapor, uv or fluorescence. However, the presence of the chiral selector in the stationary phase can mask the analyte and interfere with detection (43). 

Analytical methods iaclude thin-layer chromatography (69), gas chromatography (70), and specific methods for determining amine oxides ia detergeats (71) and foods (72). Nuclear magnetic resonance (73—75) and mass spectrometry (76) have also been used. A frequentiy used procedure for iadustrial amine oxides (77) iavolves titratioa with hydrochloric acid before and after conversion of the amine to the quaternary ammonium salt by reaction with methyl iodide. A simple, rapid quaHty control procedure has been developed for the deterrniaation of amine oxide and unreacted tertiary amine (78). 

The progress of the reaction may be followed by analytical thin-layer chromatography on alumina. The submitters used polygram pre-coated plastic sheets (Alox N/UV254) purchased from Macherey-Nagel, Inc. The plates were developed with 1 1 hexane-ether and stained with basic permanganate. The Rf of the product is 0.56. 

Nonionic surfactants, including EO-PO block copolymers, may be readily separated from anionic surfactants by a simple batch ion exchange method [21] analytical separation of EO-PO copolymers from other nonionic surfactants is possible by thin-layer chromatography (TLC) [22,23] and paper chromatography [24], and EO-PO copolymers may themselves be separated into narrow molecular weight fractions on a preparative scale by gel permeation chromatography (GPC) [25]. 

Analytical thin-layer chromatography was performed on E. Merck silica gel 60 F254 plates (0.25 mm) and compounds were visualized by dipping the plates in a cerium sulfate-ammonium molybdate solution followed by heating. 

Thin-layer chromatography (TLC) is used both for characterization of alcohol sulfates and alcohol ether sulfates and for their analysis in mixtures. This technique, combined with the use of scanning densitometers, is a quantitative analytical method. TLC is preferred to HPLC in this case as anionic surfactants do not contain strong chromophores and the refractive index detector is of low sensitivity and not suitable for gradient elution. A recent development in HPLC detector technology, the evaporative light-scattering detector, will probably overcome these sensitivity problems. 

High performance liquid chromatography (HPLC) has been by far the most important method for separating chlorophylls. Open column chromatography and thin layer chromatography are still used for clean-up procedures to isolate and separate carotenoids and other lipids from chlorophylls and for preparative applications, but both are losing importance for analytical purposes due to their low resolution and have been replaced by more effective techniques like solid phase, supercritical fluid extraction and counter current chromatography. The whole analysis should be as brief as possible, since each additional step is a potential source of epimers and allomers. 

Paper chromatography (PC) and thin layer chromatography (TLC) have been used since the 1940s. Preparative PC on Whatman 3 paper, analytical PC on Whatman 1 paper, and analytical TLC on microcrystalline cellulose, silica gel, or polyamide have been applied with a variety of solvents and the behaviors of anthocyanins have been similar in all media. Two-dimensional TLC allows the separation of several compounds and has been nsed to clarify the anthocyanin compositions of different commodities. ... 

In conclusion, synthetic dyes can be determined in solid foods and in nonalcoholic beverages and from their concentrated formulas by spectrometric methods or by several separation techniques such as TEC, HPLC, HPLC coupled with diode array or UV-Vis spectrometry, MECK, MEECK, voltammetry, and CE. ° Many analytical approaches have been used for simultaneous determinations of synthetic food additives thin layer chromatography, " " derivative spectrophotometry, adsorptive voltammetry, differential pulse polarography, and flow-through sensors for the specific determination of Sunset Yellow and its Sudan 1 subsidiary in food, " but they are generally suitable only for analyzing few-component mixtures. 

Bodoga, R, Marufoiu, C., and Coman, M.-V., Faze mobile (mobile phases), in Cromatografia pe Strat Sublire. Analiza Poluanlilor (Thin-Layer Chromatography. Pollutant Analysis), Analytical chemistry series. Technical Publishing House, Bucharest, 1995, chap. 3 and references cited therein. 

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