The Experts below are selected from a list of 7332 Experts worldwide ranked by ideXlab platform
Zhihui Hao - One of the best experts on this subject based on the ideXlab platform.
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development of an online solid phase extraction liquid chromatography mass spectrometric analysis of oxcarbazepine and its active metabolite licarbazepine from plasma with a direct injection step
Journal of Chromatography B, 2019Co-Authors: Lixuan Pan, Li Wang, Congmin Liu, Yanhong Tian, Zhihui HaoAbstract:Abstract We developed an online solid phase extraction procedure using a Hydrophilic-Lipophilic Balance sorbent, with reversed-phase liquid chromatography-high-resolution mass spectroscopy for the determination of oxcarbazepine and its active metabolite licarbazepine in plasma samples. The analytes were detected using a high-resolution Q Orbitrap mass spectrometer with targeted-selected ion monitoring (t-SIM) in positive scan mode. Under the optimized conditions, the method was linear with R2 values >0.99. The method was linear from 0.008 to 2.000 μg mL−1 and the lower limit of quantification was 0.008 μg mL−1 for both oxcarbazepine and licarbazepine. Recoveries ranged from 92.34 to 104.27% and from matrix-matched samples from 94.26 to 104.19%. The intraday and interday precision RSD values were
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development of an online solid phase extraction liquid chromatography mass spectrometric analysis of oxcarbazepine and its active metabolite licarbazepine from plasma with a direct injection step
Journal of Chromatography A, 2019Co-Authors: Lixuan Pan, Li Wang, Congmin Liu, Yanhong Tian, Zhihui HaoAbstract:We developed an online solid phase extraction procedure using a Hydrophilic-Lipophilic Balance sorbent, with reversed-phase liquid chromatography-high-resolution mass spectroscopy for the determination of oxcarbazepine and its active metabolite licarbazepine in plasma samples. The analytes were detected using a high-resolution Q Orbitrap mass spectrometer with targeted-selected ion monitoring (t-SIM) in positive scan mode. Under the optimized conditions, the method was linear with R2 values >0.99. The method was linear from 0.008 to 2.000 μg mL−1 and the lower limit of quantification was 0.008 μg mL−1 for both oxcarbazepine and licarbazepine. Recoveries ranged from 92.34 to 104.27% and from matrix-matched samples from 94.26 to 104.19%. The intraday and interday precision RSD values were <9.13% with an associated accuracy of 92.71 to 104.06%. The total time for the one step online procedure was only 8 min. This method provides a direct and accurate measurement for therapeutic drug monitoring of oxcarbazepine and its active metabolite licarbazepine.
Victoria Salvado - One of the best experts on this subject based on the ideXlab platform.
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determination of antibiotics tetracyclines and sulfonamides in biosolids by pressurized liquid extraction and liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2013Co-Authors: Annapurna Pamreddy, Manuela Hidalgo, Josef Havel, Victoria SalvadoAbstract:A robust and sensitive analytical method is developed to quantitatively determine tetracyclines and sulfonamides, two major antibiotic classes, in sewage sludge. The antibiotic agents, oxytetracycline, tetracycline, dioxycycline, chlorotetracycline, sulfathiazole, sulfapyridine, sulfamethazine and sulfamethoxazole, were extracted using pressurized liquid extraction (PLE) with citric acid at pH 3 and methanol (1:1 v/v). Clean-up of the extracts was performed by solid phase extraction (SPE) with Hydrophilic-Lipophilic Balance cartridges. Identification and quantification of the compounds is by liquid chromatography-tandem mass spectrometry in multiple reaction monitoring (MRM) mode. High recoveries ranging from 90.4 to 99.9% for sulfonamides and 96.2 to 100.9% for the tetracyclines are obtained. Method detection limits (MDLs) range from 0.6 to 4.2 ng/g for sulfonamides and 3.2 to 13 ng/g for tetracyclines. After validation, the method is applied to the analysis of sludges collected from different WWTPs in Spain.
Giovanni Muncipinto - One of the best experts on this subject based on the ideXlab platform.
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structure based design and optimization of multitarget directed 2h chromen 2 one derivatives as potent inhibitors of monoamine oxidase b and cholinesterases
Journal of Medicinal Chemistry, 2015Co-Authors: Roberta Farina, Leonardo Pisani, Marco Catto, Orazio Nicolotti, Domenico Gadaleta, Nunzio Denora, Ramon Sotootero, Estefania Mendezalvarez, Carolina Dos Santos Passos, Giovanni MuncipintoAbstract:The multifactorial nature of Alzheimer’s disease calls for the development of multitarget agents addressing key pathogenic processes. To this end, by following a docking-assisted hybridization strategy, a number of aminocoumarins were designed, prepared, and tested as monoamine oxidases (MAOs) and acetyl- and butyryl-cholinesterase (AChE and BChE) inhibitors. Highly flexible N-benzyl-N-alkyloxy coumarins 2–12 showed good inhibitory activities at MAO-B, AChE, and BChE but low selectivity. More rigid inhibitors, bearing meta- and para-xylyl linkers, displayed good inhibitory activities and high MAO-B selectivity. Compounds 21, 24, 37, and 39, the last two featuring an improved hydrophilic/lipophilic Balance, exhibited excellent activity profiles with nanomolar inhibitory potency toward hMAO-B, high hMAO-B over hMAO-A selectivity and submicromolar potency at hAChE. Cell-based assays of BBB permeation, neurotoxicity, and neuroprotection supported the potential of compound 37 as a BBB-permeant neuroprotective ...
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structure based design and optimization of multitarget directed 2h chromen 2 one derivatives as potent inhibitors of monoamine oxidase b and cholinesterases
Journal of Medicinal Chemistry, 2015Co-Authors: Roberta Farina, Leonardo Pisani, Marco Catto, Orazio Nicolotti, Domenico Gadaleta, Nunzio Denora, Ramon Sotootero, Estefania Mendezalvarez, Carolina Dos Santos Passos, Giovanni MuncipintoAbstract:The multifactorial nature of Alzheimer's disease calls for the development of multitarget agents addressing key pathogenic processes. To this end, by following a docking-assisted hybridization strategy, a number of aminocoumarins were designed, prepared, and tested as monoamine oxidases (MAOs) and acetyl- and butyryl-cholinesterase (AChE and BChE) inhibitors. Highly flexible N-benzyl-N-alkyloxy coumarins 2-12 showed good inhibitory activities at MAO-B, AChE, and BChE but low selectivity. More rigid inhibitors, bearing meta- and para-xylyl linkers, displayed good inhibitory activities and high MAO-B selectivity. Compounds 21, 24, 37, and 39, the last two featuring an improved hydrophilic/lipophilic Balance, exhibited excellent activity profiles with nanomolar inhibitory potency toward hMAO-B, high hMAO-B over hMAO-A selectivity and submicromolar potency at hAChE. Cell-based assays of BBB permeation, neurotoxicity, and neuroprotection supported the potential of compound 37 as a BBB-permeant neuroprotective agent against H2O2-induced oxidative stress with poor interaction as P-gp substrate and very low cytotoxicity.
Hosang Shin - One of the best experts on this subject based on the ideXlab platform.
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ultra trace level determination of diquat and paraquat residues in surface and drinking water using ion pair liquid chromatography with tandem mass spectrometry a comparison of direct injection and solid phase extraction methods
IEEE Journal of Solid-state Circuits, 2014Co-Authors: Jinaa Oh, Hosang ShinAbstract:: Direct injection and solid-phase extraction methods for the determination of diquat and paraquat in surface and drinking water were developed using liquid chromatography with tandem mass spectrometry. The signal intensities of analytes based on six ion-pairing reagents were compared with each other, and 12.5 mM nonafluoropentanoic acid was selected as the best suited amongst them. A clean-up method was developed using Oasis Hydrophilic-Lipophilic Balance; this was compared to the direct injection method, with respect to limits of detection, interference, precision, and accuracy. Limits of quantification of diquat and paraquat were 0.03 and 0.01 μg/L using the direct injection method, and 0.002 and 0.001 μg/L using the Hydrophilic-Lipophilic Balance method. When the Hydrophilic-Lipophilic Balance method was used to analyze target compounds in 114 surface water and 30 drinking water samples, paraquat and diquat were detected within a concentration range of 0.001-0.12 and 0.002-0.038 μg/L in surface water, respectively. When the direct injection method was used to analyze target compounds in the same samples, the detected concentrations of paraquat and diquat were within 25% in samples being >0.015 μg/L using the Hydrophilic-Lipophilic Balance method. The liquid chromatography with tandem mass spectrometry method using direct injection can thus be used for routine monitoring of paraquat and diquat in surface and drinking water.
Lixuan Pan - One of the best experts on this subject based on the ideXlab platform.
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development of an online solid phase extraction liquid chromatography mass spectrometric analysis of oxcarbazepine and its active metabolite licarbazepine from plasma with a direct injection step
Journal of Chromatography B, 2019Co-Authors: Lixuan Pan, Li Wang, Congmin Liu, Yanhong Tian, Zhihui HaoAbstract:Abstract We developed an online solid phase extraction procedure using a Hydrophilic-Lipophilic Balance sorbent, with reversed-phase liquid chromatography-high-resolution mass spectroscopy for the determination of oxcarbazepine and its active metabolite licarbazepine in plasma samples. The analytes were detected using a high-resolution Q Orbitrap mass spectrometer with targeted-selected ion monitoring (t-SIM) in positive scan mode. Under the optimized conditions, the method was linear with R2 values >0.99. The method was linear from 0.008 to 2.000 μg mL−1 and the lower limit of quantification was 0.008 μg mL−1 for both oxcarbazepine and licarbazepine. Recoveries ranged from 92.34 to 104.27% and from matrix-matched samples from 94.26 to 104.19%. The intraday and interday precision RSD values were
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development of an online solid phase extraction liquid chromatography mass spectrometric analysis of oxcarbazepine and its active metabolite licarbazepine from plasma with a direct injection step
Journal of Chromatography A, 2019Co-Authors: Lixuan Pan, Li Wang, Congmin Liu, Yanhong Tian, Zhihui HaoAbstract:We developed an online solid phase extraction procedure using a Hydrophilic-Lipophilic Balance sorbent, with reversed-phase liquid chromatography-high-resolution mass spectroscopy for the determination of oxcarbazepine and its active metabolite licarbazepine in plasma samples. The analytes were detected using a high-resolution Q Orbitrap mass spectrometer with targeted-selected ion monitoring (t-SIM) in positive scan mode. Under the optimized conditions, the method was linear with R2 values >0.99. The method was linear from 0.008 to 2.000 μg mL−1 and the lower limit of quantification was 0.008 μg mL−1 for both oxcarbazepine and licarbazepine. Recoveries ranged from 92.34 to 104.27% and from matrix-matched samples from 94.26 to 104.19%. The intraday and interday precision RSD values were <9.13% with an associated accuracy of 92.71 to 104.06%. The total time for the one step online procedure was only 8 min. This method provides a direct and accurate measurement for therapeutic drug monitoring of oxcarbazepine and its active metabolite licarbazepine.
