Paper chromatograph

Chemical Assay. In view of the similarity of their chemical and physical properties (see Table 1) (29), the main problem in the chemical analysis of the thyroid hormones is their separation. A USP procedure gives the details of a paper chromatographic separation in which T is examined for contamination by T and 3,5-diiodothyroiiine (30). Other systems are also employed (29). 

There is no other facet where thin-layer chromatography reveals its paper-chromatographic ancestry more clearly than in the question of development chambers (Fig. 56). Scaled-down paper-chromatographic chambers are still used for development to this day. From the beginning these possessed a vapor space, to allow an equilibration of the whole system for partition-chromatographic separations. The organic mobile phase was placed in the upper trough after the internal space of the chamber and, hence, the paper had been saturated, via the vapor phase, with the hydrophilic lower phase on the base of the chamber. 

Paper chromatographic separation of two forms of 4,6-dihydroxypteridine has been reported [A. Albert and D. J. Brown, J. Chem. Soc. p. 74 (1953)1, but this should be further investigated. 

Then the solution is dried on sodium sulfate, filtered, and evaporated to dryness. The residue, 1.63 grams is dissolved in hexane, this solution is filtered over 30 grams of neutral aluminum oxide, and evaporated to dryness. On paper chromatographic investigation it turned out that the obtained 19-nortestosterone 17-decanoate which at room temperature is an oil consists of a single compound, according to U.S. Patent 2,998,423. 

Some Paper Chromatographic Studies with Aspergillus niger 152 Transfructosylase, S. A. Barker, E. J. Bourne, M. Stacey, and R. B. Ward, Biochem./., 69 (1958) 60-62. 

The di- and tetraphenylpolonium could not be distinguished by the paper chromatographic method used, as was also found with Te(C6H5)4 and Te(CgH5)2, produced by decay of SblC Hs),. The Polonium 210... 

The possibility of using the hexakisamino-compound, N3P3(NH2)e (obtained by ammonolysis of NgPaCle), as a fertilizer for barley has been demonstrated.In most respects it is superior to the ammonium phosphates, although not as far as costs are concerned. There are obvious links between this application and the course of hydrolysis of NgPafNHale, which has recently been followed by paper chromatographic methods. 

Paper-chromatographic data were provided by Heyns and Vogelsang.18 Kojic acid had Rf, 0.80 developer, butanol (saturated with water)-glacial acetic acid-water (18 2 5) developing time, 22 hours spraying reagent, 0.1 % ferric chloride paper, Schleicher and Schuell, No. 2043b. 

Paper chromatographic systems have been tabulated in Table 4. 

For the same purpose, Kelly and Bryske used paper impregnated with 0.1N disodium ethylenediaminetetraacetate (EDTA) and two mobile solvents the organic phase from a mixture of n-butanol, ammonia, water (4 1 5) and the organic phase from a mixture of n-butanol, acetic acid, water (4 1 5). Disodium EDTA (0.1N) works as well as Mcllvaine s buffer when it is used to treat the paper in the method of Walton et al. (49). A circular paper chromatographic method also using paper dampened with Mcllvaine s buffer (pH 4.5) was reported by Urx et al. (50). They used a mixture of chloroform and n-butanol (4 1) as the mobile solvent. 

Singh utilized anionic dyes to detect gramicidin on paper chromatograms184. Paris and Theallet described three paper chromatographic systems for gramicidin185. Ritschel and Lercher described two solvent systems for antibioticsiOD. The solvent systems were butanol-pyridine-acetic acid-water (15 10 3 12) and water saturated butanol-water saturated ethyl ether-acetic acid (5 1 1) on Schleicher and Schull 2043b paper. The antibiotics were visualized by ninhydrin. 

Several thin-layer and paper chromatographic systems for nalidixic acid are listed below. 

Paper Chromatographic Systems Separating Neomycin from other Antibiotics... 

An enzymatic method (Kll) of estimating galactose-l-phosphate in red blood cells is simpler and less time-consuming than the paper chromatographic method, though it requires more expensive reagents and apparatus. This method closely resembles methods of assaying enzyme activity and it is, therefore, described with them in Section 4.4.1. 

BIO. Berry, H. K., Paper chromatographic method for estimation of phenylalanine. Proc. Soc. Exptl. Biol. Med. 95, 71-73 (1957). 

L7. Lockhart, J. D., and Roboz, E., Case of galactosemia identified in a four day old infant by paper chromatographic technic. Pediatrics 13, 211-217 (1954). 

Both ascending and descending paper chromatographic techniques have been used and, when thin-layer supports are employed, the use of either silica gel or cellulose is applicable. As the number of carbohydrates present in the sample is often small, the careful choice of solvent will generally make it unnecessary to perform the two-dimensional separations that are often needed when large numbers of substances, such as amino acids, are present. Reference solutions of each carbohydrate can be made up in concentrations of approximately 2 g 1 1 dissolved in an isopropanol solvent (10% v/v in water) and samples of about 10 fx should give discernible spots after separation. 

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... 

A fairly effective paper chromatographic separation of technetiiun and rhenium can be achieved by using 1 1 butanol-conc. HCl as the mobile phase . Hydrochloric acid causes selective reduction of TcO with the formation of a chloride complex which is less mobile in this system. Under this condition the R, values of technetium and rhenium, on Whatmann No. 1 paper, are 0.70 and 0.77, respectively-... 

After two decades of quantitative l.c. analyses, it has been established that, when proper precautions are taken, these methods can provide accurate and reproducible results.Quantitative l.c. measurements are usually as accurate as, and often more precise than, those obtained by spectrophotometric, " paper-chromatographic, and gas-liquid-chro-matographic methods. Both external and internal standardization have been used to translate peak height or areas into quantitative, solute-concentration values. Because peak heights are easy to measure, many methods use this parameter, and, when slightly overlapping peaks or unsteady baselines are encountered, it is the method of choice. With introduction of... 

Dangwal SK. 1981. A quantitative paper chromatographic method of separation of nitrobenzene and p-nitrobenzene in air samples. American Industrial Hygiene Association Journal 42 557... 

A variety of other paper chromatographic techniques have also been described for the determination of cortisone acetate [127-129]. 

Comparative identification of a glycosyl ester of a nucleoside pyrophosphate with an authentic sample is usually based on the identity of their ultraviolet spectra and by comparison of chromatographic mobilities of the samples and their degradation products. In addition to paper-chromatographic techniques, it may be of value to use paper... 

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