The Experts below are selected from a list of 15774 Experts worldwide ranked by ideXlab platform
Yehia Mechref - One of the best experts on this subject based on the ideXlab platform.
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quantification of Monosaccharides through multiple reaction monitoring liquid chromatography mass spectrometry using an aminopropyl column
Rapid Communications in Mass Spectrometry, 2010Co-Authors: Loubna A. Hammad, Dakota Z Derryberry, Yazen R Jmeian, Yehia MechrefAbstract:: A simple, sensitive, and reproducible quantitative liquid chromatography/tandem mass spectrometry (LC/MS/MS) method was designed for the simultaneous quantification of Monosaccharides derived from glycoprotein and blood serum using a multiple-reaction monitoring (MRM) approach. Sialic acids and neutral Monosaccharides were efficiently separated using an amino-bonded silica phase column. Neutral Monosaccharide molecules were detected as their aldol acetate anion adducts [M + CH(3)CO(2)](-) using electrospray ionization in negative ion MRM mode, while sialic acids were detected as deprotonated ions [M-H](-). The new method did not require a reduction step, and exhibited very high sensitivity to carbohydrates with limits of detection of 1 pg for the sugars studied. The linearity of the described approach spanned over three orders of magnitude (pg to ng). The method was validated for Monosaccharides originating from N-linked glycans attached to glycoproteins and glycoproteins found in human blood serum. The method effectively quantified Monosaccharides originating from as little as 1 microg of glycoprotein and 5 microL of blood serum. The method was robust, reproducible, and highly sensitive. It did not require reduction, derivatization or postcolumn addition of reagents.
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multiple reaction monitoring liquid chromatography mass spectrometry for Monosaccharide compositional analysis of glycoproteins
Journal of the American Society for Mass Spectrometry, 2009Co-Authors: Loubna A. Hammad, Marwa M Saleh, Milos V. Novotny, Yehia MechrefAbstract:A simple, sensitive, and rapid quantitative LC-MS/MS assay was designed for the simultaneous quantification of free and glycoprotein bound Monosaccharides using a multiple reaction monitoring (MRM) approach. This study represents the first example of using LC-MS/MS methods to simultaneously quantify all common glycoprotein Monosaccharides, including neutral and acidic Monosaccharides. Sialic acids and reduced forms of neutral Monosaccharides are efficiently separated using a porous graphitized carbon column. Neutral Monosaccharide molecules are detected as their alditol acetate anion adducts [M + CH3CO2]− using electrospray ionization in negative ion MRM mode, while sialic acids are detected as deprotonated ions [M − H]−. The new method exhibits very high sensitivity to carbohydrates with limits of detection as low as 1 pg for glucose, galactose, and mannose, and below 10 pg for other Monosaccharides. The linearity of the described approach spans over three orders of magnitudes (pg to ng). The method effectively quantified Monosaccharides originating from as little as 1 µg of fetuin, ribonuclease B, peroxidase, and α1-acid glycoprotein human (AGP) with results consistent with literature values and with independent CE-LIF measurements. The method is robust, rapid, and highly sensitive. It does not require derivatization or postcolumn addition of reagents.
Loubna A. Hammad - One of the best experts on this subject based on the ideXlab platform.
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quantification of Monosaccharides through multiple reaction monitoring liquid chromatography mass spectrometry using an aminopropyl column
Rapid Communications in Mass Spectrometry, 2010Co-Authors: Loubna A. Hammad, Dakota Z Derryberry, Yazen R Jmeian, Yehia MechrefAbstract:: A simple, sensitive, and reproducible quantitative liquid chromatography/tandem mass spectrometry (LC/MS/MS) method was designed for the simultaneous quantification of Monosaccharides derived from glycoprotein and blood serum using a multiple-reaction monitoring (MRM) approach. Sialic acids and neutral Monosaccharides were efficiently separated using an amino-bonded silica phase column. Neutral Monosaccharide molecules were detected as their aldol acetate anion adducts [M + CH(3)CO(2)](-) using electrospray ionization in negative ion MRM mode, while sialic acids were detected as deprotonated ions [M-H](-). The new method did not require a reduction step, and exhibited very high sensitivity to carbohydrates with limits of detection of 1 pg for the sugars studied. The linearity of the described approach spanned over three orders of magnitude (pg to ng). The method was validated for Monosaccharides originating from N-linked glycans attached to glycoproteins and glycoproteins found in human blood serum. The method effectively quantified Monosaccharides originating from as little as 1 microg of glycoprotein and 5 microL of blood serum. The method was robust, reproducible, and highly sensitive. It did not require reduction, derivatization or postcolumn addition of reagents.
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multiple reaction monitoring liquid chromatography mass spectrometry for Monosaccharide compositional analysis of glycoproteins
Journal of the American Society for Mass Spectrometry, 2009Co-Authors: Loubna A. Hammad, Marwa M Saleh, Milos V. Novotny, Yehia MechrefAbstract:A simple, sensitive, and rapid quantitative LC-MS/MS assay was designed for the simultaneous quantification of free and glycoprotein bound Monosaccharides using a multiple reaction monitoring (MRM) approach. This study represents the first example of using LC-MS/MS methods to simultaneously quantify all common glycoprotein Monosaccharides, including neutral and acidic Monosaccharides. Sialic acids and reduced forms of neutral Monosaccharides are efficiently separated using a porous graphitized carbon column. Neutral Monosaccharide molecules are detected as their alditol acetate anion adducts [M + CH3CO2]− using electrospray ionization in negative ion MRM mode, while sialic acids are detected as deprotonated ions [M − H]−. The new method exhibits very high sensitivity to carbohydrates with limits of detection as low as 1 pg for glucose, galactose, and mannose, and below 10 pg for other Monosaccharides. The linearity of the described approach spans over three orders of magnitudes (pg to ng). The method effectively quantified Monosaccharides originating from as little as 1 µg of fetuin, ribonuclease B, peroxidase, and α1-acid glycoprotein human (AGP) with results consistent with literature values and with independent CE-LIF measurements. The method is robust, rapid, and highly sensitive. It does not require derivatization or postcolumn addition of reagents.
Erika Staudacher - One of the best experts on this subject based on the ideXlab platform.
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optimization of Monosaccharide determination using anthranilic acid and 1 phenyl 3 methyl 5 pyrazolone for gastropod analysis
Analytical Biochemistry, 2011Co-Authors: Herwig Stepan, Erika StaudacherAbstract:The protein-linked glycomes and, thereby, the range of individual Monosaccharides of invertebrates differ from those of mammals due to a number of special modifications; therefore, it is necessary to adapt methods for Monosaccharide analysis in order to cover these. We optimized the labeling procedure for anthranilic acid (AA) and 1-phenyl-3-methyl-5-pyrazolone (PMP) and the subsequent separation of the labeled Monosaccharides on high-performance liquid chromatography (HPLC), with the result that we were able to identify 26 different Monosaccharides. The detection limit for anthranilic acid derivatives obtained was 65 fmol, and a reliable quantification of samples was possible up to 200 nmol under the tested conditions. PMP derivatives showed a significantly higher detection limit but allow quantification of larger sample amounts. Applying these methods on snails, their impressive set of Monosaccharide constituents, including methylated sugars, was shown.
Carole C Perry - One of the best experts on this subject based on the ideXlab platform.
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resolution of complex Monosaccharide mixtures from plant cell wall isolates by high ph anion exchange chromatography
Journal of Chromatography A, 2006Co-Authors: Heather A Currie, Carole C PerryAbstract:The use of high pH anion exchange chromatography combined with pulsed amperometric detection has been established as an effective and sensitive method for the separation, detection and quantification of Monosaccharides from a wide range of sources. However, careful examination of the separation conditions required is necessary to ensure that a complete Monosaccharide profile can be determined from structures such as the plant cell wall which is a complex network of both neutral and charged polysaccharides. This study has investigated the optimal conditions required for the analysis of such a challenging mixture, including both the stationary and mobile phase minimising co-elution and reducing method complexity. The preferred methods have been used to successfully identify and quantify the Monosaccharide components of a selected extract from the plant cell wall of the primitive higher plant Equisetum arvense.
Jian Tang - One of the best experts on this subject based on the ideXlab platform.
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sugar compositional determination of polysaccharides from dunaliella salina by modified rp hplc method of precolumn derivatization with 1 phenyl 3 methyl 5 pyrazolone
Carbohydrate Polymers, 2010Co-Authors: Yan Wu, Shangwei Chen, Min Wang, Jian TangAbstract:Abstract A modified high-performance liquid chromatography method of pre-column derivatization with 1-phenyl-3-methyl-5-pyrazolone (PMP) has been established for high resolution separation and high sensitivity determination of ten Monosaccharides simultaneously, which frequently occur in algae polysaccharides. The effects of volume proportion of acetonitrile and pH value of mobile phase (0.1 M phosphate buffer–acetonitrile) on retention and separation of the Monosaccharide derivatives were investigated with Eclipse XPB-C18 column screened out. The hydrolyzation condition of polysaccharides and derivatization procedure of hydrolysates were also optimized. The modified analysis method was used for the determination of Monosaccharide compositions in five polysaccharide fractions isolated from Duanaliella salina . The results showed that PD1 and PD4a were acidic heteropolysaccharide mainly containing glucose and galactose respectively, and PD4a contained sulfated groups; PD2 and PD3 all were a glucan; while PD4b was a complex of polysaccharide linked with nucleic acids by covalent bonds.
