Showing papers on "Paper chromatography published in 2014"

Biosynthesis of glucosyl glycerol, a compatible solute, using intermolecular transglycosylation activity of amylosucrase from Methylobacillus flagellatus KT

Abstract: A putative α-amylase gene (accession number, CP000284) of Methylobacillus flagellatus KT ATCC51484 was cloned in Escherichia coli, and its gene product was expressed and characterized. The purified recombinant enzyme (MFAS) displayed a typical amylosucrase (ASase) activity by the demonstration of multiple activities of hydrolysis, isomerization, and polymerization although it was designated as an α-amylase. The optimal reaction temperature and pH for the sucrose hydrolysis activity of MFAS were determined to be 45 °C and pH 8.5, respectively. MFAS has relatively high thermostable characteristics compared with other ASases, as demonstrated by a half-life of 19.3 min at 50 °C. MFAS also showed polymerization activity using sucrose as a sole substrate. Glycerol was transglycosylated by the intermolecular transglycosylation activity of MFAS. Two major products were observed by thin-layer chromatography and isolated by paper chromatography and recycling HPLC. Using 1H and 13C NMR, their chemical structures were determined to be (2S)-1-O-α-d-glucosyl-glycerol or (2R)-1-O-α-d-glucosyl-glycerol and 2-O-α-d-glucosyl-glycerol, in which a glucose molecule is linked to glycerol via an α-glycosidic linkage.

Sorption-catalytic determination of histamine and lysine after planar chromatography using surfactants

Abstract: The effect of ionic surfactants on the separation characteristics of histamine and lysine in model mixtures has been studied by planar chromatography. It has been demonstrated that the impregnation of paper in paper chromatography and the modification of the mobile phase with solutions of sodium n-dodecyl sulfate in thin-layer chromatography improve the selectivity of separation. Use of n-dodecyl sulfate made possible an increase in selectivity and, in some cases, sensitivity of sorption-catalytic determination. A combination of planar chromatography with the subsequent sorption-catalytic determination directly on the support made us possible to develop methods for determining histamine and lysine in the concentration range 1 × 10−12−5 × 10−11 and 1 × 10−7−1 × 10−5 M, respectively. The developed methods have been used to determine histamine in human saliva and lysine in blood plasma and pharmaceutical products.

Chloroplast pigment paper chromatography separation method

Abstract: The invention relates to a pigment paper chromatography separation method, in particular to a chloroplast pigment paper chromatography separation method. The method includes the steps that first, pigment extract is prepared and stored in a place kept out of sun for use; then, cylindrical filter paper is made; finally, sample application is performed, after sample application pigment is dried through an electric hair drier, a small hole is made in the center of the sample application pigment, one end of the cylindrical filter paper is inserted in the small hole, the other end, namely a base end, of the cylindrical filter paper is placed in a culture dish with layer unfolding agent, the round filter paper subjected to the sample application is placed on the culture dish, and chromatography starts. After four colored ribbons (beta-carotene, lutein, chlorophyll a and chlorophyll b) are all separated, the chromatography is completed. According to the method, while the chromatography separation effect, for instance, the color of the colored ribbons is pure and the edges of the colored ribbons are clear, is improved, investment of a chromatography container is reduced and saved by 60 percent, tedious processing of the chromatography filter paper is reduced, and toxic pollution generated when acetone serves as the extraction agent, and the carbon tetrachloride serves as the layer unfolding agent is reduced. The separation method is good in separation effect, time and labor are saved, and environmental pollution and toxicity are reduced.

Method for measuring L-cysteine content by HPLC (high performance liquid chromatography) process

Abstract: The invention discloses a method for measuring the L-cysteine content of an L-cysteine capsule by an HPLC (high performance liquid chromatography) process. According to the method, the L-cysteine content is measured through the chromatography process taking a mixed solvent as a flowing phase by a normal-phase silica gel bonded diol chromatographic column. Through the method, the L-cysteine content of a sample can be quickly measured.

Electrochemical Detection of Alcohol using Enzyme Sensor with Chromatography Paper and its Potential Application as halal Sensor

Abstract: This research is a preliminary study aimed to develop a `halal sensor` that can detect non-halal ingredients in food such as alcohol and pork meat. Sample solutions containing ethanol, alcohol oxidase, horseradish peroxidase, and electron mediator is dropped onto chromatography paper on top of carbon paste electrode. The relation between ethanol concentrations and open circuit potential value is studied. Despite using the paper, one are able to see that the electrode potential is dependant on the ethanol concentration and the relationship between these two parameters concurred with Nernst equation. The use of chromatography paper can produce a low cost and possible miniaturization of sensor.

Separation of Peptide Diastereomers

Abstract: Diastereomeric peptides, isomers in which one or more of the chiral centers have been converted to the opposite configuration (R or S, d or l), often possess different biological activities and/or conformational properties Therefore, the separation and determination of diastereomeric peptides is important in life sciences and particularly significant to the pharmaceutical industry for quality control of peptide synthesis and stability as well as for regulatory requirements Diastereomers differ in their physicochemical properties that can be utilized for their determination by numerous techniques In contrast to many other methods such as optical rotation, circular dichroism, differential scanning calorimetry, or infrared (IR) spectroscopy, separation techniques such as chromatography or capillary electrophoresis (CE) allow the sensitive and simultaneous identification and quantification of peptide diastereomers This chapter covers analytical-scale separation of peptide diastereomers by chromatographic methods, including paper chromatography (PC), thin-layer chromatography (TLC), gas chromatography (GC), high-performance liquid chromatography (HPLC), and CE HPLC is currently the predominantly used method for peptide diastereomer separations However, owing to the high resolving power, particularly for polar compounds, CE has been applied to the separation of diastereomeric peptides in recent years The chapter focuses on methods employing achiral stationary phases or buffers without chiral additives for the separations, although some examples of such separations, ie the use of chiral columns or chiral mobile phase additives, are mentioned Moreover, only diasteromeric peptides containing natural amino acids will be discussed

Paul Ehrlich, founder of Medicinal Chemistry, has used blotting paper for an early form of paper chromatography.

Abstract: Paul Ehrlich (1854–1915, Nobel prize in 1908 for work in immunology), one of the greatest scientists of Germany, an early pioneer of hematology, immunology and chemotherapy, was the first to develop a receptor concept (‘corpora non agunt nisi fixata’, i.e.: ‘[chemical] agents are not active if [they are] not bound [to a receptor])’. He also was one of the first who used the newly developed aniline dyes for histology (‘Ehrlich färbt am längsten’, i.e.: ‘Ehrlich stains longest’, a modification of a German proverb (‘Ehrlich währt am längsten’, i.e.: ‘honesty lasts longest’). He is famous for his use of small test tubes to study chemical reactions of minute amounts of aniline derivatives. In this way, he could select the most effective compounds for specific staining of tissues and cells (as for his discovery of mast cells or the hemogram also established by him). Less known, however, is his use of blotting paper to separate and purify these dyes and their reaction products, as described by his secretary since 1902, Marquardt (1924), in a short biographical sketch: ‘‘Whilst I have both hands full of test tubes he says ‘‘now let’s add some sulfuric acid... or let’s take acetic acid—you see! Now a little bit of ether—beautiful, isn’t it?’’ And then he pours a little bit of the fluid (from the test tubes) onto large sheets of ordinary blotting or filtering paper. This simple but most important tool, which had been omitted by Dr. Benda in his nice description of his (Ehrlich’s) laboratory, is fixed to some bookshelf, with the paper foils hanging free. Like a child, Paul Ehrlich enjoys the borders of the fluid that come in different colors, and he understands it to draw scientific conclusions from the finest nuances of these colors... Working with simpler methods is hard to imagine, but in this way Paul Ehrlich has made all his important discoveries’’. His friend and rival, Behring could perform his research supported by Hoechst laboratories. Later on, he was nobilitated and became a rich man as founder of a pharmaceutical business based on the antiserum against diphtheria (which was made possible only by Paul Ehrlich’s quantification methods). In contrast, the Prussian state gave a monthly salary of just 250 Reichsmark to Paul Ehrlich, the German Jew—who was not very religious, but never converted—and a small two room institute; but, as Ehrlich tells his friend August von Wassermann, it is ‘‘small but all mine’’ (‘klein, aber mein’), and he adds that for his work all he needs is ‘‘test tubes with a Bunsen burner and blotting paper’’ (Bäumler, 1997, p. 103—a similar statement is reported by Martha Marquardt, p. 63). Ehrlich also used test tubes for screening whether his dyes and his other chemicals would kill parasites such as spirochetes. Only by this elegant combination of two miniaturized methods, i.e., test tubes for synthesis and screening of chemicals for efficacy, and blotting paper for quality and purity control, Paul Ehrlich was able to achieve his goals of a rational drug synthesis, as stated by him in his Nobel lecture, ‘‘by as many experiments as possible and by as much quantification as possible’’. This strategy permitted him to select Salvarsan (arsphenamine) out of more than 500 candidate drugs in 1910 and thus to develop, by this ‘therapia magna sterilisans’ or ‘magic bullet’, a first causal therapy for the neurodegenerative diseases tabes dorsalis and progressive paralysis. A. J. P. Martin and R. L. M. Synge are given credit for inventing paper chromatography which did win them a Nobel prize in 1952. An editorial by Whealen (1995) says R. Horowski (&) Aramon Pharma, Königin-Luise-Str. 27, 14195 Berlin-Dahlem, Germany e-mail: r.horowski@sinoxa.eu