One-dimensional thin-layer chromatographic separation of phospholipids and lysophospholipids from tissue lipid extracts.

A modified one-dimensional thin-layer chromatographic procedure is presented for the separation from tissues of five phospholipids (phosphatidylserine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylcholine and sphingomyelin) and three lysophospholipids (lysophosphatidylserine, lysophosphatidylethanolamine and lysophosphatidylcholine). This is achieved by simple involvement of 0.4% ammonium sulphate in silica gel H and of acetone in a developing solvent as chloroform-methanol-acetic acid-acetone-water (40:25:7:4:2, v/v). The procedure is simple and the separation is reproducible. The weakness of this method is the partial degradation of phosphatidylethanolamine to lysophosphatidylethanolamine, but a method to prevent this degradation is also presented.     

Luminescence analysis of anti-inflammatory agents in blood or plasma following thin-layer chromatographic separation.

The luminescence properties of some anti-inflammatory agents and of 6-chloro-1,2,3,4-tetrahydrocarbazole-2-carbox-ylic acid, 6-chloro-9-[2-(2-methyl-5-pyridyl)ethyl]-1,2,3,4-tet-rahydrocarbazole-2-methanol.HCl, and (d,l)-6-chloro-alpha-methyl-carbazole-2-acetic acid have been examined at both ambient and cryogenic temperatures. Assays were developed for indomethacin, the tetrahydrocarbazoles, and the carbazole based upon solvent extraction from blood or plasma, thin-layer chromatographic separation of the drugs from interfering materials and phosphorimetry of the eluted materials. The solvent elution may be accomplished either by manual scraping and elution or by the use of a semiautomated elution apparatus. These two techniques were compared with respect to overall recovery and precision using both fluorometry and phosphorimetry.     

A semicrystalline inorganic ion-exchanger for thin-layer chromatographic separation of phenolic compounds

Summary The thin-layer chromatographic behaviour of 28 phenolic compounds was studied on semicrystalline stannic tungstate layers using various solvent systems of which formic acid and n-butanol-formic acid were found to be the most useful for the separation of these compounds. Dimethyl sulphoxide was found to act as a self detector for a number of phenols. An interesting feature of the study of phenols using stannic tungstate is the novel separation of different isomeric compounds. A number of binary, ternary and quarternary separations of bioanalytical and immunophysiological importance have been achieved.     

Improved quantitative thin-layer chromatographic method for the separation of cobalamin derivatives

Summary A new quantitative thin-layer chromatographic method was developed for the separation and determination of cobalamin derivatives. A mixture of acetone, acetonitrile, isopropanol, diethylamine and aqueous ammonium hydroxide as the eluent and precoated Kieselgel 60 chromatoplate as the TLC plate was used. The evaluation of the separated spots was carried out by densitometry. The method can be used for the determination of cyanocobalamin in fermentatic mixture without any cleaning or concentration procedure as well as for the purity test of cyanocobalamin and hydroxocobalamin.     

A highly effective one-minute thin-layer chromatographic separation of unconjugated tri- and dihydroxy bile acids

A rapid, miniature thin-layer chromatographic procedure has been developed for the separation of unconjugated tri- and dihydroxy bile acids. The new solvent system consisted of isooctane:diisopropyl ether:methanol:acetic acid:formamide (2:1:0.13:0.07:0.02,$\text{v}\text{v}$). Complete separation of tri- and dihydroxy bile acid fractions was easily achieved within 1 min on ITLC type SG chromatography sheets. A sensitive fluorescent visualization technique was employed. The reflected fluorescence intensity of the bile acids fluorophore spots was measured with a Farrand Mark I spectrofluorometer equipped with a thin-layer scanning attachment. The excitation and emission wavelengths were 375 and 436 nm, respectively. The above procedure has been adapted for the separation of unconjugated bile acids from serum samples. The bile acids were adsorbed onto Amberlite XAD-2, eluted with ethanol, and concentrated. Further purification was performed by a simple 3-min thin-layer chromatographic technique. This new procedure for the separation of tri- and dihydroxy bile acids is rapid, sensitive, and less complex than conventional procedures presently employed in clinical laboratories.