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The leaf alcoholic extracts of six native Argentine species of Vicia (subg. Vicilla, sect. Australis: V. gramineae, V. macrogramineae, V. epetiolaris, Y. montevidensis, V. nana and V. pampicola) and one adventitious species (subg. Vicia, sect. Vicia: V. sativa subsp. nigra) were studied by bidimentional paper chromatography. Eighty phenolic compounds were found in 107 individuals that were studied. In spite of the high intraspecific variability, observed in all the species, the chromatographic identification was possible because of the presence of specific compounds in each of them. Numerical taxonomy methods were applied to estimate the degree of similarity. The distance and association coeficients used generated congruent phenograms that showed seven main groups which agreed with the seven species that were studied and confirm the exomorphological classification. [ABSTRACT FROM AUTHOR]

Background: Chromatography permits chemical components' separation, identification, and quantification in complex mixtures. Chromatographic methods have various applications, which include the determination of an agrochemical solvent percentage and its utilization in the food-processing industry. High-Performance Liquid Chromatography (HPLC) and Gas Chromatography (GC) are essential for agriculture. Both types are used in numerous research studies today thanks to their versatility, sensitivity, reproducibility, and quickness. Aim: To discuss the main results of studies that include GC and HPLC in agriculture. Materials and methods: The study relied on a compilation of recent papers, where these techniques play a critical role in this area of science. Results: The utilization of GC and HPLC in agriculture contributed to relevant results, from the analysis of fatty acids profile in the formulation of a diet for animal nutrition, to the determination and quantification of agrochemical residues in plants, the detection of contaminants in the diets, and drug residues that compromise the lives of animals. Conclusions: The use of chromatography is an essential methodology for biochemical, toxicological, structural, and agro-industrial studies. [ABSTRACT FROM AUTHOR]

Radium-226 (226Ra) is a naturally occurring radionuclide, alpha emitter with half-life of 1 622 years originating from uranium-238 (238U). Its presence in drinking water is a major radiological hazards, which requires constant monitoring. The analytical techniques used in the determination of 226Ra generally require the stablishment of secular equilibrium and/or tedious separation of other elements. The main objetive of this paper is to demonstrate the efficiency and speed of a method of preconcentration and separation of 226Ra in natural water samples using coprecipitation with MnO2 radius and purification by cation exchange resin Dowex 50WX8. Measurement technique was Quadrupole Mass Spectrometry and associated induced plasma ICP-Q-MS. The 226Ra values obtained are in the range of 0,010-0,219 pg/L in natural waters analyzed. [ABSTRACT FROM AUTHOR]

In this paper we study the conditions of adsorption chromatography on Silica gel 60 for purification of Spacer disaccharide a component of Active Pharmaceutical Ingredient (API) of QuimiHib® vaccine. For that, we made a scale down on an analytical scale that represented at 1.8% of industrial process, indicating reproducibility between two procedures in terms of packing efficiency, purity and recovery. Dynamic binding capacity of the resin Silicagel 60 by the DSE was roughly 125±0.2 mg /mL, 3.4 times the base process. The elution profile obtained, showed the possibility of collecting a unique fraction at range 195±2 and 260±2 minutes, if it is maintained a proper packing of the chromatography resin determined by asymmetry factor from 0.8 to 1.2, which ensures a recovery of 58.9±4.5% and high purity analyzed by Thin Layer Chromatography. Adjusting the adsorption conditions increases the productivity of chromatographic operation up to 3.5 fold, indicating that it is feasible in economic terms. [ABSTRACT FROM AUTHOR]

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The exhaustive characterization of all components of our vaccine (VA-MENGOC-BC®), is a very important information to the new strategies of production and the best quality of it. Recently some regulatory authorities have recommended to remove thiomersal from vaccines altogether. In this paper we propose a disadsorption method for later chromatographic analysis of vaccine samples with or without thiomersal to know the possible antigenic variation. Three vaccine batches, stored between 2-8 °C, were studied at 0 time using different variants of disadsorption. We have demonstrated that solubilisation of the aluminium hydroxide by HCl to release the native vaccine complex is not possible and that the most efficient disadsorption method for the chromatographic analysis of VA-MENGOC-BC® is the following: the precipitate obtained from 3 mL of vaccine is diluted in 2 mL of phosphate buffer 5mM, pH 7,2-7,3, and allowed stand exactly 2 hours at 4°C. Afterwards, the samples were centrifuged and the supernatant collected. With this method we have obtained a 20% disadsorption of the sample. The result is very useful for showing the advantages of new formulations. [ABSTRACT FROM AUTHOR]

Various chromatographic methods for radiochemical control of technetium 99m-MIBI are compared. The conclusion is that chromatography on paper (Whatman 1 or FN2), using as solvent ethyl acctate:methanol (8:2) is a simple, fast method to determine the radiochemical purity of tecnetium 99m-MIBI. [ABSTRACT FROM AUTHOR]