Separation Of Basic Amino Acids Research Articles

Enantioselective separation of basic amino acids on talc

AbstractCertain amino acid derivatives (ε‐basic, anilide group) can be readily adsorbed onto various types of talc (steopac, SS20, C300, C400). For instance, talc is capable of adsorbing the amino acid esters but not the equivalent free amino acids. The types of talc which have high hydrophobicity (00, 15M00) were poor adsorbents. Two applications of these findings are presented: enhancement of the sensitivity of enzymatic tests in the presence of chromogenic substrates and enantioselective separation of ε‐basic amino acids (arginine, lysine, ornithine).

A new technique for the determination of polyamines: Overpressured ion-exchange thin-layer chromatography

An overpressured, thin-layer ion-exchange, chromatographic method was developed for the separation of basic amino acids and natural polyamines. This technique, combined with video-densitometric evaluation, appeared to be suitable for the quantitative determination of polyamines in tissue extracts prepared without any previous purification.

Operating parameters in high-performance displacement chromatography

Preparative scale separation of basic amino acids, dipeptides and nucleic acid fragments was carried out by displacement chromatography on microparticulate octadecyl-silica and siliceous strong cation-exchanger columns of dimensions generally employed in analytical high-performance liquid chromatography (HPLC). Neat aqueous carriers were used along with the following displacers: tetrabutylammonium and benzyltributylammonium salts and n-butanol.The concentration of products in the column effluent was determined by HPLC analysis. The results reveal the complexity of the displacement process and illustrate the effect of operating conditions on the rate of production and the yield of pure products. A decrease in flow-rate reduces the zone overlap, but this increase in separation is at the expense of production rate. Separation efficiency improves at elevated temperature, but without the untoward effect on the rate of production. The selection of column length was found to be a critical parameter; best results are obtained with the shortest column that allows the system to reach isotachic conditions, i.e., full development of the displacement train. The solubility of the feed components imposes constraints on the chromatographic system as far as the obtainable throughput, maximum product concentration and efficiency of separation are concerned. The yield of a component is affected by its relative amount in the feed and generally increases with the feed load provided that the length of the column is increased accordingly. The amount that can be separated in a chromatographic run increases with the column length in displacement chromatography. Octadecyl-silica is preferred over siliceous ion-exchangers as the stationary phase owing to its higher capacity, when reversed-phase chromatography can be used for the separation.

Separation of basic amino acids and related compounds on Aminex A5 resin and elution with a lithium buffer

Separation of basic amino acids and related compounds on Aminex A5 resin and elution with a lithium buffer

Separation of basic amino acids by paper electrophoresis

Alkaline solutions of amino acids absorb carbon dioxide, giving carbamates, which may appear as additional spots or streaks after paper electrophoresis in alkaline electrolytes. Interference from carbamates is prevented by carrying out electrophoresis at 50°. Mixtures of arginine, histidine, citrulline, ornithine, and lysine are resolved by paper electrophoresis at 50° and pH 9.2 in an electrolyte containing sodium carbonate and sodium hydrogen carbonate. Addition of 8-hydroxyquinoline prevents interference from impurities in the paper.

Separation of basic amino acids: IV. Electrophoretic determination of l-arginine, l-citrulline, l-histidine, l-lysine, and l-ornithine

Separation of basic amino acids: IV. Electrophoretic determination of l-arginine, l-citrulline, l-histidine, l-lysine, and l-ornithine

Electrophoretic separation of basic amino acids

Electrophoretic separation of basic amino acids

A modified method for the separation of basic amino acids on the automatic amino acid analyzer

A modified method for the separation of basic amino acids on the automatic amino acid analyzer

Cystinuria in Sweden. V. Influence of temperature on the separation of basic amino acids by high-voltage paper electrophoresis.

Cystinuria in Sweden. V. Influence of temperature on the separation of basic amino acids by high-voltage paper electrophoresis.

The use of ion exchange resins for separation of basic amino acids

AbstractThe hexone bases can be separated from each other by adsorption on a column of the cation exchange resin, Zeo‐Karb 215, and elution with bases and acids of suitable strengths. Zeo‐Karb 215 also adsorbs some of the non‐basic amino acids from protein hydrolysates, and these tend to interfere with the elution of the hexone bases. Zeo‐Karb 216 adsorbs hexone bases only from a mixture of the amino acids, but has a lower capacity and is less satisfactory than Zeo‐Karb 215 for separating the bases. The considerable quantities of eluent required for good partitions make the technique unsuitable for the large‐scale production of individual amino acids from hydrolysed proteins. Elution of adsorbed acids by shaking the resin mechanically with eluates required even greater volumes than the column procedure.