A New Reagent for Identification of Amino Acids on Thin-Layer Chromatography Plates

JPC – Journal of Planar Chromatography – Modern TLC -     

A Spray Reagent for Identification of Amino Acids on Thin-Layer Chromatography Plates

JPC – Journal of Planar Chromatography – Modern TLC -     

Two New Spray Reagents for Detection of Amino Acids on Thin-Layer Plates

JPC – Journal of Planar Chromatography – Modern TLC -     

Thin-Layer Chromatography of Dansyl Amino Acids on Polyamide

Summary Thin-Layer Chromatography of Dansyl Amino Acids on Polyamide A two-dimensional thin-layer chromatography system for the separation of the dansyl derivatives of the amino acids commonly found in proteins is described. Chromatography was performed on polyamide sheets using water-pyridine-formic acid (933.53.5 v/v) and benzene-acetic acid (4.51 v/v) as the solvents.

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Zusammenfassung Die zweidimensionale Dünnschichtchromatographie der in Proteinen gewöhnlich auftretenden Aminosäuren in Form ihrer Derivate des 1-Dime-thylaminonaphthalin-5-sulfonylchlorids (Dansylchlorids, DNS-Cl) wurde beschrieben. Sie wird auf Polyamidschichten unter Verwendung von Wasser-Pyridin-Ameisensäure (933,53,5 v/v) und Benzol: Essigsäure (4,51 v/v) als Lösungsmittel durchgeführt.

     

Mixed Supports in the Reversed-Phase Thin-Layer Chromatography of Amino Acids

Abstract

Lipophilicity of amino acids was determined by reversed-phase thin-layer chromatography using silica, aluminium oxide, cellulose, diatomaceous earth and their mixtures as supports with water as eluent.

To compare the retention behaviour of supports principal component analysis /PCA/ was applied. The potency order and the selectivity of support mixtures was calculated by the spectral map technique. Linear and logarithmic correlations were calculated between the first PCA loadings and the potency values as dependent variables and the composition of supports as independent variables.

The first eigenvalue explained more than 90% of the total variance that is only one hidden factor influenced decisively the retention. On the basis of structural differences the retention strength of amino acids on support mixtures can not be explained adequately. The first principal component responsible for the 90% of change in the retention of amino acids is related to the logarithm of support composition that is the sorbents retain their original adsorptive character also after impregnation.     

Identification of Free Amino Acids in Several Crude Extracts of Two Legumes Using Thin-Layer Chromatography

JPC – Journal of Planar Chromatography – Modern TLC -     

Thin-Layer Chromatography of Phenolic Acids on Aminopropylsilica

JPC – Journal of Planar Chromatography – Modern TLC - The possibility of using aminopropylsilica TLC plates for determination of phenolic acids has been investigated. Eighteen phenolic...     

Salting-Out and Salting-in Effects in the Reversed-Phase Thin-Layer Chromatography of Dansylated Amino Acids. Effect of Acids

Abstract

The retention of 15 dansylated amino acid derivatives was determined in aqueous solutions of formic, acetic, propionic and perchloric acid in reversed-phase thin-layer chromatography. The acids increased the retention of each derivatives at the low concentration range. This effect has been tentatively explained by the suppression of dissociation of polar groups in the solute molecules resulting in increased apparent lipophilicity (salting-out phenomenon). The higher concentrations of acid solutions decreased the retention (salting-in effect), the undissociated acid molecules probably act as an organic mobile phase. Both salting-in and salting-out phenomena can be simultaneously described by bilinear function. The polarity parameters of the amino acids, their hydrophobicity and the strength of the acid in the eluent simultaneously influence the retention.     

Three-Dimensional Thin-Layer Chromatography on Plates with Open and Closed Adsorption Layers

JPC – Journal of Planar Chromatography – Modern TLC - Two variants of three-dimensional thin-layer chromatography were realized using plates with open and sealed (closed) adsorption...     

Determination of Amino Acids by High-Performance Liquid Chromatography with Electrochemical Detection Using Ferrocene Derivatization Reagents

Abstract

Two new reagents possessing ferrocene as an electrophore and isothiocyanate reactive toward the amino group were prepared and evaluated for pre-column derivatization of amino acids in high-performance liquid chromatography with electrochemical detection. The utilities of these reagents were investigated employing glycine as a model compound. Ferrocenylisothiocyanate was more favorable with respect to reactivity and electrochemical properties. The newly developed method was applied to the determination of 4-aminobutyric acid in biological specimens.     

Use of Ninhydrin for Detection of Silylated Amino Acids

JPC – Journal of Planar Chromatography – Modern TLC -     

Normal- and Reversed-Phase Thin-Layer Chromatography of Amino Acids on Unconventional Supports with Mixed Mobile Phases Containing Dimethyl Sulfoxide

JPC – Journal of Planar Chromatography – Modern TLC - The chromatographic behavior of twenty-four amino acids has been studied on untreated and on triaryl phosphate (TAP)-impregnated...     

Nitroaromatic Reagents for Determination of Amines and Amino Acids by Liquid Chromatography/Electrochemistry

Abstract

Trinitrobenzene sulfonic acid, 2,4-dinitrofluorobenzene and 2-chloro-3,5-dinitropyridine were compared in terms of properties relevant to use as precolumn derivatization labels for amino compounds. This included consideration of chemical characteristics as well as purely detector oriented behavior. Trinitrobenzene sulfonic acid appears to be superior in all respects, yielding the most detectable derivatives with minimum production of interfering by-products.     

Ion-Pair Reversed-Phase Thin-Layer Chromatography and High-Performance Liquid Chromatography of Benzoic Acids

The separation of benzoic acids by ion-pair reversed-phase thin-layer chromatography and high-performance liquid chromatography was studied. In the optimization of separation conditions, the effect of the nature and concentration of the organic solvent, acidity of the mobile phase, concentration of salts of quaternary ammonium bases, and the length of their hydrocarbon radical on the retention of benzoic acids was studied. Conditions of the separation of a mixture of benzoic, hydroxybenzoic, aminobenzoic, and nitrobenzoic acids on Silufol plates impregnated with cetyltrimethylammonium bromide were selected; the mobile phase was isopropanol–ammonium acetate buffer solution with pH 5–dodecyltrimethylammonium bromide.     

临床化学上氨基酸、有机酸及核苷类的二维薄层色谱多相分离

在同一块薄层板上多相二维分离３０余种氨基酸、４０余种非挥发性有机酸和２０余种碱基。核苷类化合物。应用一对新的展开剂,用紫外灯－吖啶试剂－镉茚三酮试剂组合显色定位分析,改良了尿液非挥发性有机酸的溶剂萃取。尿液中此三类化合物提取物的多相二维色谱分离效果良好。     

Calculation of Partition Coefficients of Organic Reagents in Micellar Thin-Layer Chromatography

Equilibrium partition processes were quantitatively estimated for acidic reagents of the xanthene and triphenylmethane series in the system water–surfactant micelle–stationary phase. An anionic surfactant (sodium dodecyl sulfate) was used as the micelle-forming compound. Partition coefficients were calculated, and the preferential solubilization of reagents in surfactant micelles was demonstrated. Energies of reagent transfer to sodium dodecyl sulfate micelles and their adsorption energies at the stationary phase were calculated.     

The Mobile Phase Motion in Ascending Micellar Thin-Layer Chromatography with Normal-Phase Plates

JPC – Journal of Planar Chromatography – Modern TLC - The physical-chemical characteristics (surface tension and viscosity) of micellar mobile phases based on the cationic surfactant...     

Thin-Layer Chromatography of Bile Alcohols,Bile Acids and Conjugated Bile Acids

Abstract

Thin-layer chromatography of bile alcohols, bile acids and bile acid conjugates has been reviewed. Particular emphasis has been placed on the separation of the glycine and taurine conjugated bile acids as a class and as individual compounds, and on the isolation of bile alcohols and C₂₇ bile acids diastereo-isomeric at C-25.     

Use of Genetic Algorithms and Artificial Neural Networks to Predict the Resolution of Amino Acids in Thin-Layer Chromatography

JPC – Journal of Planar Chromatography – Modern TLC - A novel method is proposed for optimization of simultaneous thinlayer chromatographic separation of seven amino acids. For this...     

Recycled X-Ray Films as an Alternative Support for Thin-Layer Chromatography Plates

JPC – Journal of Planar Chromatography – Modern TLC -