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A number of porphyrins can be resolved by column partition chromatography using dimethyl sulfoxide on a silica support and cyclohexane as the mobile phase. This partition system was used as a criterion of success in the selection of new methods for the synthesis of porphyrins. The important factors which allow quantitative and reproducible evaluations of Rf values are noted, and differences in dielectric constant are recommended as a useful test for selection of other suitable chromatographic solvent pairs.

A new apparatus is described for the one-dimensional paper partition chromatography of porphyrins using the Nicholas-Riming-ton technique.The apparatus is simple and adaptable to other investigations. It embodies advantages over the conventional types of apparatus, foremost among which is the possibility of setting up a large number of samples at once under identical conditions. The apparatus can be made in all-glass form.

Mixtures of methanol, ethanol, isopropanol, n-butanol, and isoamyl alcohol were resolved by partition chromatography on Celite–water columns, using carbon tetrachloride and chloroform as developing solvents, each alcohol being determined quantitatively by dichromate oxidation of the fractions thus obtained. Only 0.5 ml. of an aqueous solution containing 1–5 mgm. of each alcohol was required for an analysis. The method was used successfully in the analysis of a mixture of volatile fermentation products containing n-butanol, isopropanol, ethanol, acetoin, diacetyl, and acetone.

1. 1. A method for the detection of Jaffe-positive substances in human blood serum using the technique of paper partition chromatography is described. 2. 2. A partial solution of the problem of apparent creatinine has been furnished by identification of pyruvate as a second Jaffe-positive compound beside creatinine in a water-soluble fraction of acetone-filtrate of sera; this finding was confirmed polarographically as well as spectrophotometrically . Up till now the quantitative significance of this substance has not been considered in connection with this problem. 3. 3. After a few preliminary experiments, paper chromatography of the insoluble residue of acetone-filtrate of serum has been left open for further investigation. It seems likely that the final solution of the problem of apparent creatinine will cover both possibilities which were discussed in the introduction, irrespectively of whether the chromatographic investigation of the insoluble fraction might show the presence of some new unknown Jaffe-positive component.

Summary A study has been made of the application of paper partition chromatography in the ergot field. A technique for the separation and identification of ergometrine and ergometrinine, when present in mixtures of total ergot alkaloids, has been described. The method has been extended so that approximately quantitative results may be obtained and, in this way, the ergometrine contents of samples of ergot have been estimated. The changes which take place in injection of ergometrine maleate B.P. 1948, during manufacture and storage have been studied chromatographically. It was found that during heat sterilisation some conversion of ergometrine to ergometrinine occurs. On storage some hydrolysis giving rise to lysergic and iso-lysergic acids takes place. By preparing chromatograms from the hydrolysates of water-insoluble ergot alkaloids, identification tests for individual alkaloids have been developed. We wish to thank Mr. H. M. Hood, B. Sc., for the photograph of a chromatogram, Mr. R. L. Grant, M. Sc., for a sample of ergometrinine and Dr. S. Smith for specimens of lysergic and iso-lysergric acids. We are also indebted to the Directors of The Wellcome Foundation for permission to publish this paper.

A simplified method for the quantitative determination of keto-acids by means of paper chromatography of their 2,4-dinitrophenylhydrazones is reported. 1. 1. The identification of these compounds on the filter paper is discussed, especially of those compounds which give more than one spot. 2. 2. The method is described in detail, espicially with regard to the pyruvic and α-ketoglutaric acid content in biological material. The recovery of these two keto-acids, starting from known aqueous solutions, averages 94%; on the basis of these results a standard curve can be drawn. According to this curve, recovery from deproteinized extracts of liver and blood averages 91.6% for pyruvic acid and 96.7% for α-ketoglutaric acid. 3. 3. Using this method the pyruvic and ketoglutaric acid content of rat blood, muscle, liver and brain is estimated.

A sharp separation of total belladonna alkaloids (atropine, hyoscyamine, and scopolamine) from chlorpheniramine1 and phenylpropanolamine2 was effected by partition column chromatography which permitted the colorimetric determination of the total belladonna alkaloids. The column utilized a stationary phase of pH 7.0 buffer with moving phases of 1:1 cyclohexane-carbon tetrachloride for removal of the chlorpheniramine, and chloroform for the elution of the alkaloids. Phenylpropanolamine was retained on the column. The method was applied to pharmaceutical formulations containing the belladonna alkaloids in combination with chlorpheniramine maleate and phenylpropanolamine hydrochloride.

1. 1. The behavior of crystalline insulin of bovine origin in partition column chromatography between the systems composed of 2-butanol equilibrated with 0.1 N solutions of perchloric, nitric, hydrobromic, hydrochloric, methylsulfonic, or hydroxyethylsulfonic acids is reported. 2. 2. Elution curves which indicated heterogeneity in the eluted fractions of insulin were noted in several of the solvent systems. 3. 3. The degree of resolution of components increased with decreasing distribution constant of the insulin in the 2-butanol-0.1 N acid systems. 4. 4. A relationship was noted between the distribution constant of the acid in 2-butanol-water and the distribution constant of the insulin in 2-butanol-0.1 N aqueous acid systems.

Based on our method for the qualitative test for steriod hormones by paper chromatography Fujisaki, et al.(1953) the quantitative determinations of several steroids were investigated. It was found that within a certain range of the amount the logarithms of each spot area of estrone, α-estradiol, dehydroepiandrosterone, Δ5-androstendiol, methyltestosterone, mcthylandrostendiol and androstane-17β-ol-3-one were directly proportional to the logarithms of the amount of the hormone, thus rendering the quantitative assay possible.

Ethanolamine-benzene systems are described for the partition chromatography of the 2,4-dinitrophenylosazone derivatives of homologous series of α-keto-aldehydes and 2,3-diketones. Each class produces a different vivid color on the chromatogram facilitating differentiation and permitting very small amounts of derivative to be followed visually down the column. A special system is also described for the chromatography of the 2,4-dinitrophenylosazone of glyoxal, the only saturated vicinal dialdehyde.

An inexpensive apparatus, economically operated, is described for rapid study of paper partition chromatography of unknown compounds. As the apparatus is small, any number can be arranged in rows for determination of suitable solvent composition, and chromatographic conditions for any particular sample. Results obtained with saccharides are presented.

SummaryMethods for identification and separation of several non-keto steroids in 10 μg quantities on paper chromatograms are described.

SummaryThe number of free amino acids found in unhydrolyzed urine by paper partition chromatography is less than that indicated by microbiological assay. No discrepancy is apparent between the methods when hydrolyzed urines are analyzed. As the sensitivities of the two methods are comparable, it is suggested that microbiological techniques are not as specific as the chromatographic procedure for the detection of urinary amino acids in the uncombined state.

THE filter paper chromatographic procedure developed by Consden, Gordon and Martin1 has proved to be very useful in the qualitative and semi-quantitative analysis of amino-acid mixtures, and appears to have possibilities for extension to a variety of other compounds2, 3.

WITHIN the last twenty years, chromatography has become increasingly important as an analytical tool. The purpose of this article is to review the uses of partition chromatography on paper, which, since its inception four years ago1, has had a wide application and which promises to become as well established as the older forms of chromatography. It should be emphasized, however, that, as mixtures, especially from biological sources, may be very complex, preliminary separations2-5 may often be necessary before paper chromatography can be used to the best possible advantage. For recent developments in all types of chromatography, the reader is referred to a number of articles indicated in footnotes 6–9.

A simple and accurate analysis for brain ascorbate at nanogram levels is described. The analysis employs anion exchange resin high performance liquid chromatography with electrochemical detection. The procedure is rapid and involves only homogenization, centrifugation and mixing of the supernatant extract with an internal standard followed by direct quantitation via liquid chromatography. The ascorbate levels of mouse, rat, and guinea pig brains analysed by this method compare well with existing literature data. The sensitivity is such that small animal brain parts can be analysed readily.

We have used the single-strand specific nuclease from Neurospora crassa and chromatography on methylated albumin-kieselguhr to purify and characterize repeated and self-complementary sequences from Escherichia coli DNA. Approximately 0.5% of the genome renatures spontaneously at zero time and another 2% renatures somewhat more rapidly than the total DNA. The early renaturing DNA has a base composition and a Tm similar to the total DNA and contains on the average 100 base pairs; the self-complementary DNA also has a base composition like E. coli but contains a mean of 170 base pairs. No evidence was obtained for the presence of a highly redundant sequence.

N(2)-guanine methyltransferase II was purified from rat liver. This enzyme methylated bulk E. coli tRNA to an extent of 7.6 nmoles of methyl groups/mg tRNA. Oligonucleotide analysis showed that N(2)-methylated guanosines were present in the modified tRNA in two sequences, namely Y-m(2)G-Cp and Y-m(2) (2)G-Cp in the ratio 4:3. Two pure tRNA(Leu) species, and tRNA(Met) (f) from E. coli were methylated with the enzyme to extents of 17, 11, and 8 nmoles of methyl groups incorporated per mg tRNA, respectively. When the methylated tRNAs were analysed no m(2) (2)G was detected and the m(2)G occurred in the tRNAs specific for leucine in a Y-m(2)G-Cp sequence and in the tRNA(Met) (f) in a sequence Y-m(2)G-Up.It is concluded that the mammalian enzyme specifically recognizes the interstem unpaired guanylate residue between the dihydrouridine arm and the anticodon arm. The absence of any detectable m(2) (2)G methylation of individual tRNA species is discussed.

Separation of simple saturated hydroxamic acids with a chain length of one to nine carbon atoms has been achieved by partition chromatography on paper. The relative merits of a number of solvents are discussed.