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The separation of dog serum lipoproteins by ultracentrifugation at a density of 1.063 is hindered by the failure of the high density fraction to accumulate in the bottom portion of the centrifuge tube. This phenomenon interferes with the quantitative recovery of pure low density lipoproteins. By paper electrophoresis, a lipid-containing protein with the mobility of a β-globulin was detected in the lowest layer of the centrifuge tube. Comparison of the preparative ultracentrifuge technique with that of dextran sulfate precipitation of β-lipoproteins revealed the suit ability of the latter procedure for the quantitative separation of β-lipoproteins. The dextran sulfate β-lipoprotein precipitate was shown to be free from α-lipoprotein by paper electrophoresis.

Two-dimensional chromatography on commercially available silica gel-loaded paper for the microanalysis of polar lipids from various tissues is described. All common phospholipids and their lyso derivatives can be reproducibly separated. As many as 22 lipid components were separated on a single chromatogram. Improved methods for staining lipids and for determining phosphorus in the chromatographic spots are reported.

SUMMARY mitochondria were incubated in air in the presence and absence Methods are described for the resolution of coenzyme Q of substrates, the ultraviolet absorption spectra of the cyclo- homologues and other lipides by means of reversed phase paper hexane extracts of such particles were shown to change in a chromatography on silicone-impregnat,ed filter paper. manner which denoted a substrate-dependent reduction of coenzyme Q (9). Such extracts have now been chromatographed Acknowledgments-The authors are indebted to Dr. David on paper, and the results have been consistent with the previous E. Green for his encouragement in the course of these studies. interpretation of the spectra of these extracts. The data given Oscar Mayer and Company kindly supplied the large quantity in Fig. 2 indicate that the extract of particles incubated in the of tissue used in the investigation. REFERENCES

A rapid chromatographic procedure was developed for the separation of sphingomyelin, phosphatidyl choline, phosphatidyl ethanolamine, phosphatidyl serine, phosphatidyl inositol, and free fatty acids on glass paper coated with sodium silicate. In addition, phosphatidyl choline and sphingomyelin were determined quantitatively by densitometry of the charred chromatogram, which was obtained by spraying the developed chromatogram with sulfuric acid and heating in an oven. The separation of phosphatides on sodium silicate-treated glass paper is more rapid than on silicic acid-impregnated paper, and the former is simpler to prepare. Preliminary application of this quantitative technique to human serum indicates that it may have a wide adaptability for the determination of phospholipids in natural products.

Pyrimidine and purine bases analysis by time of flight mass spectrometry and paper chromatography

The electrophoretic behaviour of oligodeoxynucleotides on ion-exchange papers was studied systematically with particular attention to applications in sequence analysis. Complex mixtures of larger oligonucleotides were fractionated by electrophoresis on cellulose acetate followed by t.l.c. on polyethyleneimine-cellulose. The behaviour of the oligonucleotides on polyethyleneimine-cellulose and on the two-dimensional system can provide a useful guide to their sequence. Detailed results from some of these experiments have been deposited as Supplementary Publication SUP 50031 (13 pages) at the British Library (Lending Division) (formerly the National Lending Library for Science and Technology), Boston Spa, Yorks. LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1973), 131, 5.

Two-dimensional paper chromatography was used to partition the acid-soluble phosphates in the erythrocytes of normal newborn infants, infants with erythroblastosis fetalis and adults. The inorganic phosphate concentration was higher in the fresh red cells of normal and erythroblastotic infants and rose more during incubation for four hours than in the cells of adults. The amount of erythrocyte adenosine-5’-triphosphate in the adults exceeded the quantities found in the cells of the two groups of babies. The 2,3-diphosphoglycerate level was greater in the erythrocytes of adults and infants with erythroblastosis than it was in the normal infants and incubation for four hours resulted in a sharper decrease of this compound in cells of the normal and erythroblastotic infants than in the adults.

A new paper electrophoretic method for the separation of bile acids into five groups, (1) unconjugated, (2) glycine conjugates and (3) taurine conjugates, and (4) and (5) the respective monosulfates, is described. Rapid and accurate qualitative and quantitative estimations of each group are obtained by densitometry after internal standardization and phosphomolybdate color development. The technique can be done in the routine clinical laboratory and is useful for the detection of diseases affecting the enterohepatic circulation of bile acids.

A method to exclude mites and other contaminants from test tube cultures is described. It consists in covering the mouths of the tubes with cigarette paper which is applied by pressing the flamed r...

In an attempt to elucidate the nature of ruthenium red reactions of substances in histochemical specimens, the effects of added electrolytes upon the reactions of model polyanions on filter paper and in tissue have been studied according to the Scott-Dorling type of critical electrolyte concentration (CEC) principle. The results obtained in the present experiments indicate that any of the three anionic groups, sulfates, phosphates and carboxyls can be responsible for the ruthenium red reactions of polyanions and that the dye binds to polyanions largely forming a salt type of linkage. However, ruthenium red is not a dye of choice for use in stainings based upon the CEC principle, inasmuch as certain moieties of the dye cations appear to interact with cationic electrolytes.

SUMMARY Chromatographic procedures for the detection and evaluation of oxygenated fatty acids are described. Emphasis has been placed on epoxy acids, but these methods promise to be of great value in studies of all classes of oxygenated acids. Paper chromatography of fatty acids and their esters has been developed for the examination of mixtures containing oxygenated derivatives. The method of adsorption chromatography on thin layers of silicic acid has been shown to be a powerful tool in studies of epoxy acids and hydroxy acids. Gas-liquid chromatography (GLC) of epoxy esters has been studied using both polar and nonpolar columns and has great utility in the detection and analysis of these compounds in mixtures. These methods have been applied to the examination of the epoxy components of six seed oils. Thin-layer and GLC proved particularly useful in this study and together demonstrated the presence of at least three distinct epoxy acids in each of these oils. Some conclusions as to the probable structures of these epoxy components are presented on the basis of their chromatographic characteristics in relation to known substances.

Commercial silica gel loaded filter paper has been found to give good separations of neutral lipids and phospholipids. Unidimensional or two-dimensional chromatography can be used. Rat liver lipids and C14-algae lipids were studied. An advantage over thin-layer chromatography is that several spot tests can be applied on the same chromatogram.

Improvements in the detection of phospholipids on paper chromatograms by neutron activation (with the formation of P32-compounds) have been made. Formaldehyde-treated papers were subjected to low neutron dosage after chromatographic development and the resulting radioactive spots were detected by automatic scanning and autoradiography.