The Experts below are selected from a list of 76269 Experts worldwide ranked by ideXlab platform
Shuji Kodama - One of the best experts on this subject based on the ideXlab platform.
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enantioseparation of hydroxyeicosatetraenoic acids by hydroxypropyl γ cyclodextrin modified micellar electrokinetic chromatography
Electrophoresis, 2016Co-Authors: Shuji Kodama, Shota Nakajima, Hiromichi Ozaki, Ryota Takemoto, Yutaka Itabashi, A KuksisAbstract:Complete resolution of hydroxyeicosatetraenoic acid (HETE) enantiomers was achieved using hydroxypropyl-γ-cycodextrin (HP-γ-CD)-modified MEKC. The optimum running conditions were determined to be utilizing a 30 mM phosphate-15 mM borate buffer (pH 9.0) containing 30 mM HP-γ-CD and 75 mM SDS as the BGE, application of +30 kV as the Effective Voltage, and carrying out the experiment at 15°C. The eluents were detected at 235 nm. The method was used successfully for the simultaneous separations of (S)- and (R)-enantiomers of regioisomeric 8-, 11-, 12-, and 15-HETEs. Subsequently, the optimized method was applied to evaluate the stereochemistry of 8- and 12-HETEs from the marine red algae, Gracilaria vermiculophylla and Gracilaria arcuata, respectively. The 8-HETE was found to be a mixture of 98% (R)-enantiomer and 2% (S)-enantiomer, while the 12-HETE was a mixture of 98% (S)-enantiomer and 2% (R)-enantiomer. The present study demonstrates that the HP-γ-CD-modified MEKC method is simple and sensitive and provides unambiguous information on the configuration of natural and synthetic HETEs. This article is protected by copyright. All rights reserved
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enantioseparation of vinclozolin by gamma cyclodextrin modified micellar electrokinetic chromatography
Journal of Agricultural and Food Chemistry, 2002Co-Authors: Shuji Kodama, Atsushi Yamamoto, Yukio Saitoh, Akinobu Matsunaga, Kazumasa Okamura, Ryoichi Kizu, Kazuichi HayakawaAbstract:Cyclodextrin-modified micellar electrokinetic chromatography was applied to the enantioseparation of vinclozolin, which has been used as a fungicide and has an anti-androgenic activity, using γ-cyclodextrin together with sodium dodecyl sulfate. Factors affecting the chiral resolution and migration time of vinclozolin were studied. The optimum running conditions were found to be 20 mM phosphate−5 mM borate buffer (pH 8.5) containing 50 mM γ-cyclodextrin and 100 mM sodium dodecyl sulfate with an Effective Voltage of 20 kV at 20 °C using direct detection at 203 nm. Under these conditions, the resolution (Rs) of racemic vinclozolin was approximately 2.1. The sample was concentrated by solid-phase extraction and was fractionated by HPLC. The peak area ratio of (+)- and (−)-vinclozolins in wine was found to be 2:3, namely, not racemic, suggesting that degradation rates were different between (+)- and (−)-vinclozolins. The anti-androgenic activities of (+)- and (−)-vinclozolins on dihydrotestosterone-induced tra...
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direct chiral resolution of tartaric acid in food products by ligand exchange capillary electrophoresis using copper ii d quinic acid as a chiral selector
Journal of Chromatography A, 2001Co-Authors: Shuji Kodama, Atsushi Yamamoto, Akinobu Matsunaga, Kazuichi HayakawaAbstract:Abstract Chiral resolution of native dl -tartaric acid was performed by ligand-exchange capillary electrophoresis using copper(II)– d -quinic acid as a chiral selector. Factors affecting chiral resolution, migration time, and peak area of tartaric acid were studied. The running conditions for optimum separation of tartaric acid were found to be 1 mM copper(II) sulfate–10 mM d -quinic acid (pH 5.0) with an Effective Voltage of −15 kV at 30°C, using direct detection at 250 nm, and resolution of racemic tartaric acid was approximately 1.3. With this system, chiral resolution of dl -tartaric acid in food products was conducted successfully.
Kazuichi Hayakawa - One of the best experts on this subject based on the ideXlab platform.
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enantioseparation of vinclozolin by gamma cyclodextrin modified micellar electrokinetic chromatography
Journal of Agricultural and Food Chemistry, 2002Co-Authors: Shuji Kodama, Atsushi Yamamoto, Yukio Saitoh, Akinobu Matsunaga, Kazumasa Okamura, Ryoichi Kizu, Kazuichi HayakawaAbstract:Cyclodextrin-modified micellar electrokinetic chromatography was applied to the enantioseparation of vinclozolin, which has been used as a fungicide and has an anti-androgenic activity, using γ-cyclodextrin together with sodium dodecyl sulfate. Factors affecting the chiral resolution and migration time of vinclozolin were studied. The optimum running conditions were found to be 20 mM phosphate−5 mM borate buffer (pH 8.5) containing 50 mM γ-cyclodextrin and 100 mM sodium dodecyl sulfate with an Effective Voltage of 20 kV at 20 °C using direct detection at 203 nm. Under these conditions, the resolution (Rs) of racemic vinclozolin was approximately 2.1. The sample was concentrated by solid-phase extraction and was fractionated by HPLC. The peak area ratio of (+)- and (−)-vinclozolins in wine was found to be 2:3, namely, not racemic, suggesting that degradation rates were different between (+)- and (−)-vinclozolins. The anti-androgenic activities of (+)- and (−)-vinclozolins on dihydrotestosterone-induced tra...
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direct chiral resolution of tartaric acid in food products by ligand exchange capillary electrophoresis using copper ii d quinic acid as a chiral selector
Journal of Chromatography A, 2001Co-Authors: Shuji Kodama, Atsushi Yamamoto, Akinobu Matsunaga, Kazuichi HayakawaAbstract:Abstract Chiral resolution of native dl -tartaric acid was performed by ligand-exchange capillary electrophoresis using copper(II)– d -quinic acid as a chiral selector. Factors affecting chiral resolution, migration time, and peak area of tartaric acid were studied. The running conditions for optimum separation of tartaric acid were found to be 1 mM copper(II) sulfate–10 mM d -quinic acid (pH 5.0) with an Effective Voltage of −15 kV at 30°C, using direct detection at 250 nm, and resolution of racemic tartaric acid was approximately 1.3. With this system, chiral resolution of dl -tartaric acid in food products was conducted successfully.
Yue Wang - One of the best experts on this subject based on the ideXlab platform.
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alcohol soluble isoindigo derivative iidth nsb as a novel modifier of zno in inverted polymer solar cells
ACS Applied Materials & Interfaces, 2017Co-Authors: Biao Guo, Jianxiong Han, Jing Qiu, Yuqian Sun, Yue WangAbstract:Alcohol-soluble isoindigo derivative with thiophene groups and sulfobetaine zwitterions, IIDTh-NSB was applied as a novel modifier of ZnO in inverted polymer solar cells (i-PSCs). When IIDTh-NSB (0.2 mg/mL) was spin-coated on ZnO as an electron transport layer (ETL), power conversion efficiency (PCE) of the PTB7:PC71BM based i-PSCs reached 8.88%, which is a 20% improvement of that of 7.40% for the device with the ZnO-only ETL. If ZnO was doped by IIDTh-NSB of 1.0 wt %, the PCE of 8.50% could be achieved in the i-PSCs. Combined measurements of capacitance-Voltage characteristics, carrier mobility, and photocurrent density-Effective Voltage characteristics revealed that incorporating IIDTh-NSB as the modifier of ZnO by coating or doping enhanced the built-in potential, charge carrier density and mobility, exciton dissociation, and charge carrier extraction in the i-PSCs because of the improved interfacial contact between the photoactive layer and ZnO as shown in water contact angle measurements and atomic force microscopy images. Finally, impedance spectroscopy investigation provided strong lines of evidence that incorporating IIDTh-NSB as the modifier of ZnO led to the great enhancement in short-circuit current density and fill factor. Furthermore, all the devices with IIDTh-NSB as a modifier of ZnO presented better stability than the device with ZnO-only. These findings suggest that IIDTh-NSB is an Effective and competitive material for modification of ZnO in the i-PSCs.
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Alcohol-Soluble Isoindigo Derivative IIDTh-NSB as a Novel Modifier of ZnO in Inverted Polymer Solar Cells
2017Co-Authors: Biao Guo, Jianxiong Han, Jing Qiu, Yuqian Sun, Yue WangAbstract:Alcohol-soluble isoindigo derivative with thiophene groups and sulfobetaine zwitterions, IIDTh-NSB was applied as a novel modifier of ZnO in inverted polymer solar cells (i-PSCs). When IIDTh-NSB (0.2 mg/mL) was spin-coated on ZnO as an electron transport layer (ETL), power conversion efficiency (PCE) of the PTB7:PC71BM based i-PSCs reached 8.88%, which is a 20% improvement of that of 7.40% for the device with the ZnO-only ETL. If ZnO was doped by IIDTh-NSB of 1.0 wt %, the PCE of 8.50% could be achieved in the i-PSCs. Combined measurements of capacitance–Voltage characteristics, carrier mobility, and photocurrent density-Effective Voltage characteristics revealed that incorporating IIDTh-NSB as the modifier of ZnO by coating or doping enhanced the built-in potential, charge carrier density and mobility, exciton dissociation, and charge carrier extraction in the i-PSCs because of the improved interfacial contact between the photoactive layer and ZnO as shown in water contact angle measurements and atomic force microscopy images. Finally, impedance spectroscopy investigation provided strong lines of evidence that incorporating IIDTh-NSB as the modifier of ZnO led to the great enhancement in short-circuit current density and fill factor. Furthermore, all the devices with IIDTh-NSB as a modifier of ZnO presented better stability than the device with ZnO-only. These findings suggest that IIDTh-NSB is an Effective and competitive material for modification of ZnO in the i-PSCs
Biao Guo - One of the best experts on this subject based on the ideXlab platform.
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alcohol soluble isoindigo derivative iidth nsb as a novel modifier of zno in inverted polymer solar cells
ACS Applied Materials & Interfaces, 2017Co-Authors: Biao Guo, Jianxiong Han, Jing Qiu, Yuqian Sun, Yue WangAbstract:Alcohol-soluble isoindigo derivative with thiophene groups and sulfobetaine zwitterions, IIDTh-NSB was applied as a novel modifier of ZnO in inverted polymer solar cells (i-PSCs). When IIDTh-NSB (0.2 mg/mL) was spin-coated on ZnO as an electron transport layer (ETL), power conversion efficiency (PCE) of the PTB7:PC71BM based i-PSCs reached 8.88%, which is a 20% improvement of that of 7.40% for the device with the ZnO-only ETL. If ZnO was doped by IIDTh-NSB of 1.0 wt %, the PCE of 8.50% could be achieved in the i-PSCs. Combined measurements of capacitance-Voltage characteristics, carrier mobility, and photocurrent density-Effective Voltage characteristics revealed that incorporating IIDTh-NSB as the modifier of ZnO by coating or doping enhanced the built-in potential, charge carrier density and mobility, exciton dissociation, and charge carrier extraction in the i-PSCs because of the improved interfacial contact between the photoactive layer and ZnO as shown in water contact angle measurements and atomic force microscopy images. Finally, impedance spectroscopy investigation provided strong lines of evidence that incorporating IIDTh-NSB as the modifier of ZnO led to the great enhancement in short-circuit current density and fill factor. Furthermore, all the devices with IIDTh-NSB as a modifier of ZnO presented better stability than the device with ZnO-only. These findings suggest that IIDTh-NSB is an Effective and competitive material for modification of ZnO in the i-PSCs.
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Alcohol-Soluble Isoindigo Derivative IIDTh-NSB as a Novel Modifier of ZnO in Inverted Polymer Solar Cells
2017Co-Authors: Biao Guo, Jianxiong Han, Jing Qiu, Yuqian Sun, Yue WangAbstract:Alcohol-soluble isoindigo derivative with thiophene groups and sulfobetaine zwitterions, IIDTh-NSB was applied as a novel modifier of ZnO in inverted polymer solar cells (i-PSCs). When IIDTh-NSB (0.2 mg/mL) was spin-coated on ZnO as an electron transport layer (ETL), power conversion efficiency (PCE) of the PTB7:PC71BM based i-PSCs reached 8.88%, which is a 20% improvement of that of 7.40% for the device with the ZnO-only ETL. If ZnO was doped by IIDTh-NSB of 1.0 wt %, the PCE of 8.50% could be achieved in the i-PSCs. Combined measurements of capacitance–Voltage characteristics, carrier mobility, and photocurrent density-Effective Voltage characteristics revealed that incorporating IIDTh-NSB as the modifier of ZnO by coating or doping enhanced the built-in potential, charge carrier density and mobility, exciton dissociation, and charge carrier extraction in the i-PSCs because of the improved interfacial contact between the photoactive layer and ZnO as shown in water contact angle measurements and atomic force microscopy images. Finally, impedance spectroscopy investigation provided strong lines of evidence that incorporating IIDTh-NSB as the modifier of ZnO led to the great enhancement in short-circuit current density and fill factor. Furthermore, all the devices with IIDTh-NSB as a modifier of ZnO presented better stability than the device with ZnO-only. These findings suggest that IIDTh-NSB is an Effective and competitive material for modification of ZnO in the i-PSCs
Akinobu Matsunaga - One of the best experts on this subject based on the ideXlab platform.
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enantioseparation of vinclozolin by gamma cyclodextrin modified micellar electrokinetic chromatography
Journal of Agricultural and Food Chemistry, 2002Co-Authors: Shuji Kodama, Atsushi Yamamoto, Yukio Saitoh, Akinobu Matsunaga, Kazumasa Okamura, Ryoichi Kizu, Kazuichi HayakawaAbstract:Cyclodextrin-modified micellar electrokinetic chromatography was applied to the enantioseparation of vinclozolin, which has been used as a fungicide and has an anti-androgenic activity, using γ-cyclodextrin together with sodium dodecyl sulfate. Factors affecting the chiral resolution and migration time of vinclozolin were studied. The optimum running conditions were found to be 20 mM phosphate−5 mM borate buffer (pH 8.5) containing 50 mM γ-cyclodextrin and 100 mM sodium dodecyl sulfate with an Effective Voltage of 20 kV at 20 °C using direct detection at 203 nm. Under these conditions, the resolution (Rs) of racemic vinclozolin was approximately 2.1. The sample was concentrated by solid-phase extraction and was fractionated by HPLC. The peak area ratio of (+)- and (−)-vinclozolins in wine was found to be 2:3, namely, not racemic, suggesting that degradation rates were different between (+)- and (−)-vinclozolins. The anti-androgenic activities of (+)- and (−)-vinclozolins on dihydrotestosterone-induced tra...
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direct chiral resolution of tartaric acid in food products by ligand exchange capillary electrophoresis using copper ii d quinic acid as a chiral selector
Journal of Chromatography A, 2001Co-Authors: Shuji Kodama, Atsushi Yamamoto, Akinobu Matsunaga, Kazuichi HayakawaAbstract:Abstract Chiral resolution of native dl -tartaric acid was performed by ligand-exchange capillary electrophoresis using copper(II)– d -quinic acid as a chiral selector. Factors affecting chiral resolution, migration time, and peak area of tartaric acid were studied. The running conditions for optimum separation of tartaric acid were found to be 1 mM copper(II) sulfate–10 mM d -quinic acid (pH 5.0) with an Effective Voltage of −15 kV at 30°C, using direct detection at 250 nm, and resolution of racemic tartaric acid was approximately 1.3. With this system, chiral resolution of dl -tartaric acid in food products was conducted successfully.
