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Robert T. Kennedy - One of the best experts on this subject based on the ideXlab platform.
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Determination of amines and phenolic acids in wine with Benzoyl Chloride derivatization and liquid chromatography-mass spectrometry.
Journal of chromatography. A, 2017Co-Authors: Paige A. Malec, Marianna Oteri, Veronica Inferrera, Francesco Cacciola, Luigi Mondello, Robert T. KennedyAbstract:Abstract Amine and phenolic metabolites are important contributors to the flavor and health effects of many foods, including wine. Determination of these metabolites often involves UV detection following separation by liquid chromatography. While this is sufficient for some applications, chemical derivatization with LC–MS provides greater sensitivity and selectivity relative to LC-UV. We have developed an assay for 56 amine and phenolic metabolites in wine using Benzoyl Chloride derivatization and LC–MS. Isotopically labeled Benzoyl Chloride was used to prepare internal standards for each metabolite. Nanomolar limits of detection were achieved for all metabolites. To demonstrate the application of this assay, we compared metabolite profiles from Merlot and Cabernet Sauvignon wines from California and Australia. We found five metabolites which were significantly different when grouped by varietal, while twenty-four were different when grouped by location of production. This shows that the method can identify differences between various wines.
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Benzoyl Chloride derivatization with liquid chromatography mass spectrometry for targeted metabolomics of neurochemicals in biological samples
Journal of Chromatography A, 2016Co-Authors: Jenny-marie T Wong, Omar S. Mabrouk, Paige A. Malec, Monica Dus, Robert T. KennedyAbstract:Widely targeted metabolomic assays are useful because they provide quantitative data on large groups of related compounds. We report a high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method that utilizes Benzoyl Chloride labeling for 70 neurologically relevant compounds, including catecholamines, indoleamines, amino acids, polyamines, trace amines, antioxidants, energy compounds, and their metabolites. The method includes neurotransmitters and metabolites found in both vertebrates and insects. This method was applied to analyze microdialysate from rats, human cerebrospinal fluid, human serum, fly tissue homogenate, and fly hemolymph, demonstrating its broad versatility for multiple physiological contexts and model systems. Limits of detection for most assayed compounds were below 10nM, relative standard deviations were below 10%, and carryover was less than 5% for 70 compounds separated in 20min, with a total analysis time of 33min. This broadly applicable method provides robust monitoring of multiple analytes, utilizes small sample sizes, and can be applied to diverse matrices. The assay will be of value for evaluating normal physiological changes in metabolism in neurochemical systems. The results demonstrate the utility of Benzoyl Chloride labeling with HPLC-MS/MS for widely targeted metabolomics assays.
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Benzoyl Chloride derivatization with liquid chromatography???mass spectrometry for targeted metabolomics of neurochemicals in biological samples
Journal of chromatography. A, 2016Co-Authors: Jenny-marie T Wong, Omar S. Mabrouk, Paige A. Malec, Monica Dus, Robert T. KennedyAbstract:Widely targeted metabolomic assays are useful because they provide quantitative data on large groups of related compounds. We report a high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method that utilizes Benzoyl Chloride labeling for 70 neurologically relevant compounds, including catecholamines, indoleamines, amino acids, polyamines, trace amines, antioxidants, energy compounds, and their metabolites. The method includes neurotransmitters and metabolites found in both vertebrates and insects. This method was applied to analyze microdialysate from rats, human cerebrospinal fluid, human serum, fly tissue homogenate, and fly hemolymph, demonstrating its broad versatility for multiple physiological contexts and model systems. Limits of detection for most assayed compounds were below 10nM, relative standard deviations were below 10%, and carryover was less than 5% for 70 compounds separated in 20min, with a total analysis time of 33min. This broadly applicable method provides robust monitoring of multiple analytes, utilizes small sample sizes, and can be applied to diverse matrices. The assay will be of value for evaluating normal physiological changes in metabolism in neurochemical systems. The results demonstrate the utility of Benzoyl Chloride labeling with HPLC-MS/MS for widely targeted metabolomics assays.
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in vivo neurochemical monitoring using Benzoyl Chloride derivatization and liquid chromatography mass spectrometry
Analytical Chemistry, 2012Co-Authors: Peng Song, Omar S. Mabrouk, Neil D. Hershey, Robert T. KennedyAbstract:In vivo neurochemical monitoring using microdialysis sampling is important in neuroscience because it allows correlation of neurotransmission with behavior, disease state, and drug concentrations in the intact brain. A significant limitation of current practice is that different assays are utilized for measuring each class of neurotransmitter. We present a high performance liquid chromatography (HPLC)–tandem mass spectrometry method that utilizes Benzoyl Chloride for determination of the most common low molecular weight neurotransmitters and metabolites. In this method, 17 analytes were separated in 8 min. The limit of detection was 0.03–0.2 nM for monoamine neurotransmitters, 0.05–11 nM for monoamine metabolites, 2–250 nM for amino acids, 0.5 nM for acetylcholine, 2 nM for histamine, and 25 nM for adenosine at sample volume of 5 μL. Relative standard deviation for repeated analysis at concentrations expected in vivo averaged 7% (n = 3). Commercially available 13C Benzoyl Chloride was used to generate iso...
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In Vivo Neurochemical Monitoring using Benzoyl Chloride Derivatization and Liquid Chromatography – Mass Spectrometry
Analytical chemistry, 2011Co-Authors: Peng Song, Omar S. Mabrouk, Neil D. Hershey, Robert T. KennedyAbstract:In vivo neurochemical monitoring using microdialysis sampling is important in neuroscience because it allows correlation of neurotransmission with behavior, disease state, and drug concentrations in the intact brain. A significant limitation of current practice is that different assays are utilized for measuring each class of neurotransmitter. We present a high performance liquid chromatography (HPLC)–tandem mass spectrometry method that utilizes Benzoyl Chloride for determination of the most common low molecular weight neurotransmitters and metabolites. In this method, 17 analytes were separated in 8 min. The limit of detection was 0.03–0.2 nM for monoamine neurotransmitters, 0.05–11 nM for monoamine metabolites, 2–250 nM for amino acids, 0.5 nM for acetylcholine, 2 nM for histamine, and 25 nM for adenosine at sample volume of 5 μL. Relative standard deviation for repeated analysis at concentrations expected in vivo averaged 7% (n = 3). Commercially available 13C Benzoyl Chloride was used to generate iso...
Jing-jer Jwo - One of the best experts on this subject based on the ideXlab platform.
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STUDY OF THE REACTION OF GLYCINE AND Benzoyl Chloride UNDER INVERSE PHASE TRANSFER CATALYSIS
Chemical Engineering Communications, 2000Co-Authors: Maw-ling Wang, Jing-jer JwoAbstract:Abstract This study examined the feasibility of reacting Benzoyl Chloride (PhCOCl) and sodium glycinate (H2NCH2COOH) catalyzed by 4-dimethylaminopyridine (DMAP) in an alkaline (NaOH) aqueous solution/dichloromethane two-phase medium. This catalyzed reaction of Benzoyl Chloride and sodium glycinate was described by a pseudo-first-order rate law. The hydrolysis of Benzoyl Chloride in the two*phase reaction was neglected on the specified reaction conditions. In addition, the effects of operating conditions on the conversion of Benzoyl Chloride and the reaction rate. According to those results, the reaction rate decreases with an increasing concentration of Benzoyl Chloride, which contradicts the general rate law of reaction kinetics, This peculiar phenomenon could be accounted for altering the interfacial property due to the change of the chemical property of reactants and intermediate, and the interaction between reactants and intermediate which was transferred from organic phase to aqueous phase.
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Kinetics of the reaction of Benzoyl Chloride and sodium carboxylate under inverse phase-transfer catalysis
Journal of Molecular Catalysis A: Chemical, 1995Co-Authors: Maw-ling Wang, Jing-jer JwoAbstract:The reaction of Benzoyl Chloride and sodium carboxylate using pyridine 1-oxide (PNO) as an inverse phase-transfer catalyst in a system of the two phases H2O and CH2Cl2 was investigated. Carboxylate ions including formate, acetate, propionate, 2-methylpropanoate, pentanoate, hexanoate, heptanoate and octanoate were selected to compare their reactivities. The rate of reaction depended on the concentration of pyridine 1-oxide (PNO) in the organic phase. The concentration of carboxylate ion affected the distribution of pyridine 1-oxide (PNO) between the organic and aqueous phases. The rate of reaction thus depended on the concentration of the carboxylate ion even though the rate-determining step occurred in the organic phase.
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Study of the Pyridine 1-Oxide-Catalyzed Two-Phase Reversible Exchange Reaction of Benzoyl Chloride and Butanoate Ion
Bulletin of the Chemical Society of Japan, 1994Co-Authors: Maw-ling Wang, Jing-jer JwoAbstract:The reaction of Benzoyl Chloride (PhCOCl) and butanoate ion (PrCOO−) catalyzed by pyridine 1-oxide (PNO) in the medium H2O/CH2Cl2 leads to equilibrium with butanoyl Chloride (PrCOCl) and benzoate ion (PhCOO−) and vice versa. The rate-determining step takes place in the organic phase and PrCOCl is much more reactive than PhCOCl. The effects of Chloride ion, hydroxide ion, pyridine 1-oxide, reactants and temperature on the reaction rate and the equilibrium conversion of acyl Chloride (RCOCl) were investigated. Satisfactory detailed mechanistic interpretations of the kinetic results are given.
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Effect of the organic solvents on the pyridine 1-oxide-catalyzed reaction of Benzoyl Chloride and acetate ion in a two-phase medium
Industrial & Engineering Chemistry Research, 1994Co-Authors: Maw-ling Wang, Jing-jer JwoAbstract:The substitution reaction of Benzoyl Chloride (PhCOCl) and sodium acetate (CH 3 COONa) using pyridine 1-oxide (PNO) as the inverse phase-transfer catalyst (IPTC) in a two-phase system of organic solvent and water was studied. The effects of the polarity of the organic solvent on the conversion of Benzoyl Chloride, the yield of the main product acetic benzoic anhydride (PhCOOCOCH 3 ), and the reaction rate was investigated. A larger reaction rate was observed for a more polar organic solvent. In order to confirm this deduction, mixtures of inert organic substances of varied polarity were used as organic solvents in a two-phase reaction. The effects of such solvents, pyridine 1-oxide (PNO), and temperature on the conversion of Benzoyl Chloride, the reaction rate, and the yield of the main product acetic benzoic anhydride (PhCOOCOCH 3 ) were also investigated in detail
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Inverse phase transfer catalysis. Kinetics and mechanism of the pyridine 1-oxide catalyzed substitution reaction of Benzoyl Chloride and benzoate ion in a two-phase water/dichloromethane medium
The Journal of Organic Chemistry, 1992Co-Authors: Chao Shiun Kuo, Jing-jer JwoAbstract:The two-phase reaction of Benzoyl Chloride (PhCOCl) and benzoate ion with pyridine 1-oxide (PNO) as the inverse phase transfer catalyst yields both the substitution product (benzoic anhydride) and the hydrolysis product (benzoic acid). A high yield (>95%) of benzoic anhydride can be obtained if a polar organic solvent like dichloromethane is used. Under appropriate conditions, this reaction follows the rate law-d[PhCOCl] org /dt =(k h +k c [PNO] iaq )[PhCOCl] org
Omar S. Mabrouk - One of the best experts on this subject based on the ideXlab platform.
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Benzoyl Chloride derivatization with liquid chromatography mass spectrometry for targeted metabolomics of neurochemicals in biological samples
Journal of Chromatography A, 2016Co-Authors: Jenny-marie T Wong, Omar S. Mabrouk, Paige A. Malec, Monica Dus, Robert T. KennedyAbstract:Widely targeted metabolomic assays are useful because they provide quantitative data on large groups of related compounds. We report a high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method that utilizes Benzoyl Chloride labeling for 70 neurologically relevant compounds, including catecholamines, indoleamines, amino acids, polyamines, trace amines, antioxidants, energy compounds, and their metabolites. The method includes neurotransmitters and metabolites found in both vertebrates and insects. This method was applied to analyze microdialysate from rats, human cerebrospinal fluid, human serum, fly tissue homogenate, and fly hemolymph, demonstrating its broad versatility for multiple physiological contexts and model systems. Limits of detection for most assayed compounds were below 10nM, relative standard deviations were below 10%, and carryover was less than 5% for 70 compounds separated in 20min, with a total analysis time of 33min. This broadly applicable method provides robust monitoring of multiple analytes, utilizes small sample sizes, and can be applied to diverse matrices. The assay will be of value for evaluating normal physiological changes in metabolism in neurochemical systems. The results demonstrate the utility of Benzoyl Chloride labeling with HPLC-MS/MS for widely targeted metabolomics assays.
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Benzoyl Chloride derivatization with liquid chromatography???mass spectrometry for targeted metabolomics of neurochemicals in biological samples
Journal of chromatography. A, 2016Co-Authors: Jenny-marie T Wong, Omar S. Mabrouk, Paige A. Malec, Monica Dus, Robert T. KennedyAbstract:Widely targeted metabolomic assays are useful because they provide quantitative data on large groups of related compounds. We report a high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method that utilizes Benzoyl Chloride labeling for 70 neurologically relevant compounds, including catecholamines, indoleamines, amino acids, polyamines, trace amines, antioxidants, energy compounds, and their metabolites. The method includes neurotransmitters and metabolites found in both vertebrates and insects. This method was applied to analyze microdialysate from rats, human cerebrospinal fluid, human serum, fly tissue homogenate, and fly hemolymph, demonstrating its broad versatility for multiple physiological contexts and model systems. Limits of detection for most assayed compounds were below 10nM, relative standard deviations were below 10%, and carryover was less than 5% for 70 compounds separated in 20min, with a total analysis time of 33min. This broadly applicable method provides robust monitoring of multiple analytes, utilizes small sample sizes, and can be applied to diverse matrices. The assay will be of value for evaluating normal physiological changes in metabolism in neurochemical systems. The results demonstrate the utility of Benzoyl Chloride labeling with HPLC-MS/MS for widely targeted metabolomics assays.
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in vivo neurochemical monitoring using Benzoyl Chloride derivatization and liquid chromatography mass spectrometry
Analytical Chemistry, 2012Co-Authors: Peng Song, Omar S. Mabrouk, Neil D. Hershey, Robert T. KennedyAbstract:In vivo neurochemical monitoring using microdialysis sampling is important in neuroscience because it allows correlation of neurotransmission with behavior, disease state, and drug concentrations in the intact brain. A significant limitation of current practice is that different assays are utilized for measuring each class of neurotransmitter. We present a high performance liquid chromatography (HPLC)–tandem mass spectrometry method that utilizes Benzoyl Chloride for determination of the most common low molecular weight neurotransmitters and metabolites. In this method, 17 analytes were separated in 8 min. The limit of detection was 0.03–0.2 nM for monoamine neurotransmitters, 0.05–11 nM for monoamine metabolites, 2–250 nM for amino acids, 0.5 nM for acetylcholine, 2 nM for histamine, and 25 nM for adenosine at sample volume of 5 μL. Relative standard deviation for repeated analysis at concentrations expected in vivo averaged 7% (n = 3). Commercially available 13C Benzoyl Chloride was used to generate iso...
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In Vivo Neurochemical Monitoring using Benzoyl Chloride Derivatization and Liquid Chromatography – Mass Spectrometry
Analytical chemistry, 2011Co-Authors: Peng Song, Omar S. Mabrouk, Neil D. Hershey, Robert T. KennedyAbstract:In vivo neurochemical monitoring using microdialysis sampling is important in neuroscience because it allows correlation of neurotransmission with behavior, disease state, and drug concentrations in the intact brain. A significant limitation of current practice is that different assays are utilized for measuring each class of neurotransmitter. We present a high performance liquid chromatography (HPLC)–tandem mass spectrometry method that utilizes Benzoyl Chloride for determination of the most common low molecular weight neurotransmitters and metabolites. In this method, 17 analytes were separated in 8 min. The limit of detection was 0.03–0.2 nM for monoamine neurotransmitters, 0.05–11 nM for monoamine metabolites, 2–250 nM for amino acids, 0.5 nM for acetylcholine, 2 nM for histamine, and 25 nM for adenosine at sample volume of 5 μL. Relative standard deviation for repeated analysis at concentrations expected in vivo averaged 7% (n = 3). Commercially available 13C Benzoyl Chloride was used to generate iso...
Zi Gao - One of the best experts on this subject based on the ideXlab platform.
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Benzoylation of toluene with Benzoyl Chloride on Al‐promoted sulfated solid superacids
Catalysis Letters, 1998Co-Authors: Yongde Xia, Weiming Hua, Zi GaoAbstract:The catalytic performance of Al‐promoted sulfated zirconia and sulfated titania for Benzoylation of toluene with Benzoyl Chloride has been investigated. The incorporation of Al enhances the catalytic activity of the sulfated oxide catalysts prominently owing to an increase in superacidity of the catalysts. Al‐promoted sulfated zirconia catalysts are more active than the analogous sulfated titania catalysts because of their higher superacidity. In particular, SO42-–/3%Al2O3–ZrO2 is a good clean catalyst for the Benzoylation reaction, which gives 100% yield of methylbenzophenones after on stream for 12 h at 110 °C.
Peng Song - One of the best experts on this subject based on the ideXlab platform.
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in vivo neurochemical monitoring using Benzoyl Chloride derivatization and liquid chromatography mass spectrometry
Analytical Chemistry, 2012Co-Authors: Peng Song, Omar S. Mabrouk, Neil D. Hershey, Robert T. KennedyAbstract:In vivo neurochemical monitoring using microdialysis sampling is important in neuroscience because it allows correlation of neurotransmission with behavior, disease state, and drug concentrations in the intact brain. A significant limitation of current practice is that different assays are utilized for measuring each class of neurotransmitter. We present a high performance liquid chromatography (HPLC)–tandem mass spectrometry method that utilizes Benzoyl Chloride for determination of the most common low molecular weight neurotransmitters and metabolites. In this method, 17 analytes were separated in 8 min. The limit of detection was 0.03–0.2 nM for monoamine neurotransmitters, 0.05–11 nM for monoamine metabolites, 2–250 nM for amino acids, 0.5 nM for acetylcholine, 2 nM for histamine, and 25 nM for adenosine at sample volume of 5 μL. Relative standard deviation for repeated analysis at concentrations expected in vivo averaged 7% (n = 3). Commercially available 13C Benzoyl Chloride was used to generate iso...
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In Vivo Neurochemical Monitoring using Benzoyl Chloride Derivatization and Liquid Chromatography – Mass Spectrometry
Analytical chemistry, 2011Co-Authors: Peng Song, Omar S. Mabrouk, Neil D. Hershey, Robert T. KennedyAbstract:In vivo neurochemical monitoring using microdialysis sampling is important in neuroscience because it allows correlation of neurotransmission with behavior, disease state, and drug concentrations in the intact brain. A significant limitation of current practice is that different assays are utilized for measuring each class of neurotransmitter. We present a high performance liquid chromatography (HPLC)–tandem mass spectrometry method that utilizes Benzoyl Chloride for determination of the most common low molecular weight neurotransmitters and metabolites. In this method, 17 analytes were separated in 8 min. The limit of detection was 0.03–0.2 nM for monoamine neurotransmitters, 0.05–11 nM for monoamine metabolites, 2–250 nM for amino acids, 0.5 nM for acetylcholine, 2 nM for histamine, and 25 nM for adenosine at sample volume of 5 μL. Relative standard deviation for repeated analysis at concentrations expected in vivo averaged 7% (n = 3). Commercially available 13C Benzoyl Chloride was used to generate iso...