Chromatography spotting

G. Guiochon and A. M. Siouffi, Study of the performance of thin-layer chromatography. Spot capacity in thin-layer cltromatography , 7. Chromatogr. 245 1-20 (1982). 

Sequaris J.M.L., Koglin E., Direct analysis of high-performance thin-layer chromatography spots of nucleic purine derivatives by surface-enhanced raman-scattering spectrometry, Anal. Chem. 1987 59 525-527. 

The diuretic and cholagog effect of Ononis arvensis motivated the development of a new two-dimensional paper chromatographic and TLC method for the measurement of onion in its roots and aerial parts. Samples were dried, ground and extracted with methanol (70 per cent, w/v) for 2 h. The supernatant was diluted and used for TLC separation on a cellulose stationary phase. The first eluent was 3 per cent formic acid, and the second was n-butanol-acetic acid-water (4 1 5, v/v) for both TLC and paper chromatography. Spots were scraped off, extracted with methanol and the absorption was measued at 260 nm. It was found that the average ononin content in roots and aerial parts was 0.153 0.0278 (per cent) and 0.498 0.045 (per cent), respectively. Because of the simplicity, the method was... 

Figure 1. Tracings of separation of total capsaicinoids of capsicum extracts and reference pure compounds by paper chromatography Spot (1) red capsicum Spot (2) natural capsaicinoids pure Spot (3) green capsicum fresh and Spot (4) synthetic capsaicin (C) color (F) fat, and (Cv), capsaicinoids/capsaicin ((27) and...

Separation of amino acids and their identification in different mixtures are frequent tasks encountered in biochemistry. Thin layer chromatography is a fast, simple, and inexpensive approach to attain this goal. Because some of the components are UV-inactive, other methods, such as vibrational spectroscopy, should be applied for detection and identification. Comparative study based on Raman spectroscopy of thin layer chromatography spots of some weak Raman scatterers (essential amino acids) was carried out using four different visible and near-infrared laser radiation wavelengths 532, 633,785, and 1064 nm. The best results were obtained with simple silica gel plates. 

Istvan, K. Keresztury, G. Szep, A. Normal Raman and surface enhanced Raman spectroscopic experiments with thin layer chromatography spots of essential amino acids using different laser excitation sources. Spectrochim. Acta, Part A Mol. Biomol. Spectrosc. 2003, 59, 1709-1723. 

Paper chromatography spot urine and spots of amino acids it isthoughtto contain on the paperrun chromatogram usinga suitable solvent (water) develop colourless spots by spraying with ninhydrin. 

Chang,T., Lay, J.Q. Jr., Francel, R.J. (1984) Direct analysis of thin-layer chromatography spots by fast atom bombardment mass spectrometry. Analytical Chemistry, 56, 109-111. 

Chen, X. and Smart, R.B. 1992. Direct analysis of thin-layer chromatography spots by thermal extraction-gas chromatography-miass spectroscopy, J. Ghromatogr. Sci., 30 192-196. 

Polyvinyl chloride Aqueous extractants Barium, cadmium, lead and zinc organo-metallic stabilizers Thin-layer chromatography, spots located with aq. sodium rhodizoate [100]... 

Chang, T. T., J. 0. Lay, and J. F. Rudolph Direct Analysis of Thin-Layer Chromatography Spots by Fast Atom Bombardment Mass Spectrometry. Analyt. Chemistry 56, 109 (1984). 

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). 

Chemical stabiUty studies are monitored by siUca gel thin-layer chromatography (dc) or by high performance Hquid chromatography (hplc) using a reverse-phase C g coated column (24). Hplc peaks or dc spots are visualized by thek uv absorption at 245 nm the tic spots can also be detected by ceric sulfate or phosphomolybdic acid staining. 

Amino acids have high melting or decomposition points and are best examined for purity by paper or thin layer chromatography. The spots are developed with ninhydrin. Customary methods for the purification of small quantities of amino acids obtained from natural sources (i.e. l-5g) are ion-exchange chromatography (see Chapter 1). For general treatment of amino acids see Greenstein and Winitz [The Amino Acids, Vols 1-3, J.Wiley Sons, New York 1961] and individual amino acids in Chapters 4 and 6. 

Purified by paper chromatography using /crt-butanol-water, cutting out the main spot and eluting with water. Also purified by adsorption onto an apo-flavodoxin column, followed by elution and freeze drying Crystd from acidic aqueous soln. [Mayhew and Strating Eur J Biochem 59 539 1976.]... 

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