The Experts below are selected from a list of 213 Experts worldwide ranked by ideXlab platform

Annie J Narkates - One of the best experts on this subject based on the ideXlab platform.

  • quantitation of type i iii and v collagens in human tissue samples by high performance Liquid Chromatography of selected cyanogen bromide peptides
    Analytical Biochemistry, 1991
    Co-Authors: Edward J Miller, Donald K Furuto, Annie J Narkates
    Abstract:

    Abstract A method to determine the proportions of the major fiber-forming collagens (types I, III, and V) in noncartilaginous human tissues is presented. The procedure relies on direct solubilization of tissue collagen as cyanogen bromide peptides. The peptides are subjected to cation exchange Chromatography followed by gel permeation Chromatography in a manner consistent with the rapid resolution and quantitation of relatively low-molecular-weight marker peptides for each collagen. The marker peptides utilized for type I, III, and V collagens are α1(I)-CB2, α1(III)-CB2, and α1(V)-CB1, respectively. Quantitation of the peptides is attained as a function of ultraviolet absorbance during gel permeation Chromatography. The nature of the marker peptides, the use of high-performance Liquid Chromatography Techniques, and quantitation of the peptides by ultraviolet absorbance renders the method suitably rapid, sensitive, and accurate for routine evaluations of collagen composition. The utility of the method is illustrated in the presentation of analyses on specimens of placental membranes and blood vessel walls.

Luigi Mondello - One of the best experts on this subject based on the ideXlab platform.

  • determination of the triacylglycerol fraction in fish oil by comprehensive Liquid Chromatography Techniques with the support of gas Chromatography and mass spectrometry data
    Analytical and Bioanalytical Chemistry, 2015
    Co-Authors: Marco Beccaria, Paola Dugo, Francesco Cacciola, Rosaria Costa, Giuseppe Sullini, Elisa Grasso, Luigi Mondello
    Abstract:

    Fish oil made from menhaden (Brevoortia tyrannus) can be used as a dietary supplement for the presence of high levels of the long-chained omega-3 fatty acids, viz. epentaenoic and docosahexanoic. In this work, for the first time, two different multidimensional approaches were developed and compared, in terms of peak capacity, for triacylglycerol characterization. In particular, silver ion Chromatography with a silver-ion column and non-aqueous reverse-phase Liquid Chromatography with a C18 column were tested in both comprehensive (stop-flow) and off-line modes. The use of mass spectra attained by atmospheric pressure chemical ionization for both LC approaches, and the fatty acids methyl esters profile of menhaden oil obtained by gas Chromatography analysis, greatly supported the elucidation of the triacylglycerol content in menhaden oil. The off-line approach afforded a better separation and, thus, higher peak capacity to allow identifying and semiquantifying more than 250 triacylglycerols. Such a huge number has never been reported for a menhaden oil sample.The main disadvantage of such an approach over the stop-flow one was the longer analysis time, mainly attributable to solvent exchange between the two dimensions.

  • high efficiency Liquid Chromatography Techniques coupled to mass spectrometry for the characterization of mate extracts
    Journal of Chromatography A, 2009
    Co-Authors: Paola Dugo, Francesco Cacciola, Paola Donato, Rosângela Assis Jacques, Elina Bastos Caramao, Luigi Mondello
    Abstract:

    Abstract There is growing interest related to rapid screening and full characterization of the constituents of plants with medicinal properties; among these, “Mate” or Yerba Mate is a tea-like beverage widely consumed in South America, obtained from the dried leaves of Ilex paraguariensis . The high content in polyphenols accounts for in vitro and in vivo antioxidant activity of the extracts obtained from this plant; on the other hand, the high complexity of the samples extracted, depending on the method employed, may preclude complete resolution by conventional HPLC Techniques. For this purpose, a comprehensive two-dimensional Liquid Chromatography (LC × LC) system, comprised of an RP-Amide first dimension and a partially porous octadecylsilica column in the second dimension, has been compared with a one-dimensional system. The latter was operated using a partially porous octadecylsilica column, with diode array (DAD) and electrospray/ion trap-time of flight (ESI/IT-TOF) detection for the most complex extracts. The employment of the hybrid mass spectrometer allowed unequivocal identification of several compounds in the mate extracts. Using LC × LC–MS 3 , it was possible to discriminate between congeners of chlorogenic acids, along with monoacyl- and diacylchlorogenic acid esters.

P. Kappel - One of the best experts on this subject based on the ideXlab platform.

  • Characteristics of a new automated blood sampling system for positron emission tomography
    IEEE Transactions on Nuclear Science, 1995
    Co-Authors: L. Eriksson, M. Ingvar, G. Rosenqvist, S. Stone-elander, T. Ekdahl, P. Kappel
    Abstract:

    A new commercially available automated blood sampling system (ABSS) for positron emission tomography has been evaluated. The system uses a single BGO crystal and detects with high efficiency the annihilation radiation from tracers, labelled with positron emitting isotopes, in arterial blood. In addition the possibilities to use the ABSS as a detector in the analysis of the plasma samples with Liquid Chromatography Techniques under flow conditions has been explored.

  • Characteristics of a new automated blood sampling system for positron emission tomography
    Proceedings of 1994 IEEE Nuclear Science Symposium - NSS'94, 1994
    Co-Authors: L. Eriksson, M. Ingvar, G. Rosenqvist, S. Stone-elander, T. Ekdahl, P. Kappel
    Abstract:

    A new automated blood sampling system (ABSS) for positron emission tomography has been evaluated. The system uses a single BGO crystal and detects with high efficiency the annihilation radiation from tracers, labelled with positron emitting isotopes, in arterial blood. In addition the possibilities to use the ABSS as a detector in the analysis of the plasma samples with Liquid Chromatography Techniques under flow conditions has been explored.

Dusan Berek - One of the best experts on this subject based on the ideXlab platform.

Yulin Feng - One of the best experts on this subject based on the ideXlab platform.

  • Rapid identification of erythrocyte phospholipids in Sprague-Dawley rats by ultra high performance Liquid Chromatography with electrospray ionization quadrupole time-of-flight tandem mass spectrometry
    Journal of Separation Science, 2015
    Co-Authors: J Pi, P. Zeng, Sheng Yang, Xia Wu, Yulin Feng
    Abstract:

    A rapid, sensitive, and reliable approach for analyzing five kinds of erythrocyte phospholipids in Sprague-Dawley rats was provided by ultra high performance Liquid Chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry with MassLynxTM MassFragment. Improving conventional high performance Liquid Chromatography Techniques, ultra high performance Liquid Chromatography integrated with quadrupole time-of-flight tandem mass spectrometry offers high sensitivity and increased analytical speed by using columns packed with sub-2 μm particles (1.7 μm), which allows a faster separation to be achieved. Through this method, 83 phospholipids were tentatively characterized based on their mass spectra and tandem mass spectra, as well as by matching the in-house formula database within a mass error of 5 ppm, including 40 phosphatidylcholines, 24 phosphatidyl ethanolamines, three phosphatidylinositols, six phosphatidylserines, and ten sphingomyelins. Our present results proved that the established method could be used to qualitatively analyze complex erythrocyte phospholipids in Sprague-Dawley rats and provide a useful data base for pharmacology and phospholipidomics to seek potential biomarkers of disease prediction. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.