The Experts below are selected from a list of 9078 Experts worldwide ranked by ideXlab platform
Fujio Ohishi - One of the best experts on this subject based on the ideXlab platform.
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WEATHERING ANALYSIS OF Modified Poly (2,6-DIMETHYL-1,4-PHENYLENE ETHER) BY THERMAL ANALYSIS
Recent Advances in Environmentally Compatible Polymers, 2020Co-Authors: Y. Nishmoto, Yasutaka Nagai, Ken Ichi Sato, Fujio OhishiAbstract:ABSTRACT Weathering analysis of a Modified Poly (2,6-dimethyl-1,4-phenylene ether) using thermal analytical methods was studied. It was found that the evolution of CO2 and H2O was detected at the initial decomposition of degraded Modified PPE. We report the application of dynamic load TMA (DL-TMA) using compressive oscillating stress to the analysis of surface degradation of plastics. The results from the DL-TMA method have close relation with the molecular weight of the region of the surface. It was proved that the surface degradation is detectable with high sensitivity without any pretreatment by applying DL-TMA.
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Sensitive detection of degradation of Modified Poly(2,6-dimethyl-1,4-phenylene ether) by dynamic load thermomechanical analysis
Polymer Degradation and Stability, 2000Co-Authors: Yuko Nishimoto, Yasutaka Nagai, Ken Ichi Sato, Fujio OhishiAbstract:Weathering of a Modified Poly(2,6-dimethyl-1,4-phenylene ether) (m-PPE) was studied. It was found that the glass transition temperature or the complex modulus of the exposed sample in bulky state was almost the same as that of the unexposed sample. SEC, IR and TG-FT IR measurements proved that only the surface region of the exposed sample degraded. We report the application of dynamic load thermomechanical analysis (DL-TMA) using compressive oscillating load to the analysis of surface degradation of m-PPE. The results from the DL-TMA method have close relation with the molecular weight of the surface region. It was proved that the surface degradation is detectable in the bulk state with high sensitivity by applying DL-TMA.
Mansoor M. Amiji - One of the best experts on this subject based on the ideXlab platform.
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Poly ethylene oxide Modified Poly β amino ester nanoparticles as a ph sensitive biodegradable system for paclitaxel delivery
Journal of Controlled Release, 2003Co-Authors: Anupama Potineni, Robert Langer, David M. Lynn, Mansoor M. AmijiAbstract:The main objective of this study was to develop and characterize a pH-sensitive biodegradable Polymeric nanoparticulate system for tumor-selective paclitaxel delivery. A representative hydrophobic Poly(β-amino ester) (Poly-1) was synthesized by conjugate addition of 4,4′-trimethyldipiperidine with 1,4-butanediol diacrylate. Poly-1 (Mn 10,000 daltons) nanoparticles were prepared by the controlled solvent displacement method in an ethanol–water system in the presence of Pluronic® F-108, a Poly(ethylene oxide) (PEO)-containing non-ionic surfactant. Control and PEO-Modified nanoparticles were characterized by Coulter counter, scanning electron microscopy (SEM), zeta potential measurements, and electron spectroscopy for chemical analysis (ESCA). Polymer degradation studies were performed in phosphate-buffered saline (PBS, pH 7.4) at 37 °C. Paclitaxel loading capacities and efficiencies were determined and release studies were performed in Tween®-80 (0.1%, w/v)-containing PBS at 37 °C. Control and PEO-Modified nanoparticles, labeled with rhodamine-123, were incubated with BT-20 cells to examine the uptake and cellular distribution as a function of time. PEO-Modified nanoparticles with an average size of 100–150 nm and a positive surface charge of 37.0 mV were prepared. SEM analysis showed distinct smooth, spherical particles. The ether (–C–O–) peak of the C1s envelope in ESCA confirmed the surface presence of PEO chains. Polymer biodegradation studies showed that almost 85% of the starting material degraded after 6 days. The maximum paclitaxel loading efficiency attained was 97% at 1.0% (w/w) of the drug. Paclitaxel release studies showed that approximately 10% was released in the first 24 h, 80% after 3 days, and the entire content was released in approximately 5 days. After 1 h of incubation, a large fraction of the administered control and PEO-Modified Poly-1 nanoparticles was internalized in BT-20 cells. Results of this study demonstrate that PEO-Modified Poly-1 nanoparticles could provide increased therapeutic benefit by delivering the encapsulated drug to solid tumors.
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Poly(ethylene oxide)-Modified Poly(β-amino ester) nanoparticles as a pH-sensitive biodegradable system for paclitaxel delivery
Journal of Controlled Release, 2003Co-Authors: Anupama Potineni, Robert Langer, David M. Lynn, Mansoor M. AmijiAbstract:The main objective of this study was to develop and characterize a pH-sensitive biodegradable Polymeric nanoparticulate system for tumor-selective paclitaxel delivery. A representative hydrophobic Poly(β-amino ester) (Poly-1) was synthesized by conjugate addition of 4,4′-trimethyldipiperidine with 1,4-butanediol diacrylate. Poly-1 (Mn10,000 daltons) nanoparticles were prepared by the controlled solvent displacement method in an ethanol-water system in the presence of Pluronic® F-108, a Poly(ethylene oxide) (PEO)-containing non-ionic surfactant. Control and PEO-Modified nanoparticles were characterized by Coulter counter, scanning electron microscopy (SEM), zeta potential measurements, and electron spectroscopy for chemical analysis (ESCA). Polymer degradation studies were performed in phosphate-buffered saline (PBS, pH 7.4) at 37°C. Paclitaxel loading capacities and efficiencies were determined and release studies were performed in Tween®-80 (0.1%, w/v)-containing PBS at 37°C. Control and PEO-Modified nanoparticles, labeled with rhodamine-123, were incubated with BT-20 cells to examine the uptake and cellular distribution as a function of time. PEO-Modified nanoparticles with an average size of 100-150 nm and a positive surface charge of 37.0 mV were prepared. SEM analysis showed distinct smooth, spherical particles. The ether (-C-O-) peak of the C1senvelope in ESCA confirmed the surface presence of PEO chains. Polymer biodegradation studies showed that almost 85% of the starting material degraded after 6 days. The maximum paclitaxel loading efficiency attained was 97% at 1.0% (w/w) of the drug. Paclitaxel release studies showed that approximately 10% was released in the first 24 h, 80% after 3 days, and the entire content was released in approximately 5 days. After 1 h of incubation, a large fraction of the administered control and PEO-Modified Poly-1 nanoparticles was internalized in BT-20 cells. Results of this study demonstrate that PEO-Modified Poly-1 nanoparticles could provide increased therapeutic benefit by delivering the encapsulated drug to solid tumors. © 2002 Elsevier Science B.V. All rights reserved.
Anupama Potineni - One of the best experts on this subject based on the ideXlab platform.
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Poly ethylene oxide Modified Poly β amino ester nanoparticles as a ph sensitive biodegradable system for paclitaxel delivery
Journal of Controlled Release, 2003Co-Authors: Anupama Potineni, Robert Langer, David M. Lynn, Mansoor M. AmijiAbstract:The main objective of this study was to develop and characterize a pH-sensitive biodegradable Polymeric nanoparticulate system for tumor-selective paclitaxel delivery. A representative hydrophobic Poly(β-amino ester) (Poly-1) was synthesized by conjugate addition of 4,4′-trimethyldipiperidine with 1,4-butanediol diacrylate. Poly-1 (Mn 10,000 daltons) nanoparticles were prepared by the controlled solvent displacement method in an ethanol–water system in the presence of Pluronic® F-108, a Poly(ethylene oxide) (PEO)-containing non-ionic surfactant. Control and PEO-Modified nanoparticles were characterized by Coulter counter, scanning electron microscopy (SEM), zeta potential measurements, and electron spectroscopy for chemical analysis (ESCA). Polymer degradation studies were performed in phosphate-buffered saline (PBS, pH 7.4) at 37 °C. Paclitaxel loading capacities and efficiencies were determined and release studies were performed in Tween®-80 (0.1%, w/v)-containing PBS at 37 °C. Control and PEO-Modified nanoparticles, labeled with rhodamine-123, were incubated with BT-20 cells to examine the uptake and cellular distribution as a function of time. PEO-Modified nanoparticles with an average size of 100–150 nm and a positive surface charge of 37.0 mV were prepared. SEM analysis showed distinct smooth, spherical particles. The ether (–C–O–) peak of the C1s envelope in ESCA confirmed the surface presence of PEO chains. Polymer biodegradation studies showed that almost 85% of the starting material degraded after 6 days. The maximum paclitaxel loading efficiency attained was 97% at 1.0% (w/w) of the drug. Paclitaxel release studies showed that approximately 10% was released in the first 24 h, 80% after 3 days, and the entire content was released in approximately 5 days. After 1 h of incubation, a large fraction of the administered control and PEO-Modified Poly-1 nanoparticles was internalized in BT-20 cells. Results of this study demonstrate that PEO-Modified Poly-1 nanoparticles could provide increased therapeutic benefit by delivering the encapsulated drug to solid tumors.
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Poly(ethylene oxide)-Modified Poly(β-amino ester) nanoparticles as a pH-sensitive biodegradable system for paclitaxel delivery
Journal of Controlled Release, 2003Co-Authors: Anupama Potineni, Robert Langer, David M. Lynn, Mansoor M. AmijiAbstract:The main objective of this study was to develop and characterize a pH-sensitive biodegradable Polymeric nanoparticulate system for tumor-selective paclitaxel delivery. A representative hydrophobic Poly(β-amino ester) (Poly-1) was synthesized by conjugate addition of 4,4′-trimethyldipiperidine with 1,4-butanediol diacrylate. Poly-1 (Mn10,000 daltons) nanoparticles were prepared by the controlled solvent displacement method in an ethanol-water system in the presence of Pluronic® F-108, a Poly(ethylene oxide) (PEO)-containing non-ionic surfactant. Control and PEO-Modified nanoparticles were characterized by Coulter counter, scanning electron microscopy (SEM), zeta potential measurements, and electron spectroscopy for chemical analysis (ESCA). Polymer degradation studies were performed in phosphate-buffered saline (PBS, pH 7.4) at 37°C. Paclitaxel loading capacities and efficiencies were determined and release studies were performed in Tween®-80 (0.1%, w/v)-containing PBS at 37°C. Control and PEO-Modified nanoparticles, labeled with rhodamine-123, were incubated with BT-20 cells to examine the uptake and cellular distribution as a function of time. PEO-Modified nanoparticles with an average size of 100-150 nm and a positive surface charge of 37.0 mV were prepared. SEM analysis showed distinct smooth, spherical particles. The ether (-C-O-) peak of the C1senvelope in ESCA confirmed the surface presence of PEO chains. Polymer biodegradation studies showed that almost 85% of the starting material degraded after 6 days. The maximum paclitaxel loading efficiency attained was 97% at 1.0% (w/w) of the drug. Paclitaxel release studies showed that approximately 10% was released in the first 24 h, 80% after 3 days, and the entire content was released in approximately 5 days. After 1 h of incubation, a large fraction of the administered control and PEO-Modified Poly-1 nanoparticles was internalized in BT-20 cells. Results of this study demonstrate that PEO-Modified Poly-1 nanoparticles could provide increased therapeutic benefit by delivering the encapsulated drug to solid tumors. © 2002 Elsevier Science B.V. All rights reserved.
Yuko Nishimoto - One of the best experts on this subject based on the ideXlab platform.
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Sensitive detection of degradation of Modified Poly(2,6-dimethyl-1,4-phenylene ether) by dynamic load thermomechanical analysis
Polymer Degradation and Stability, 2000Co-Authors: Yuko Nishimoto, Yasutaka Nagai, Ken Ichi Sato, Fujio OhishiAbstract:Weathering of a Modified Poly(2,6-dimethyl-1,4-phenylene ether) (m-PPE) was studied. It was found that the glass transition temperature or the complex modulus of the exposed sample in bulky state was almost the same as that of the unexposed sample. SEC, IR and TG-FT IR measurements proved that only the surface region of the exposed sample degraded. We report the application of dynamic load thermomechanical analysis (DL-TMA) using compressive oscillating load to the analysis of surface degradation of m-PPE. The results from the DL-TMA method have close relation with the molecular weight of the surface region. It was proved that the surface degradation is detectable in the bulk state with high sensitivity by applying DL-TMA.
Ken Ichi Sato - One of the best experts on this subject based on the ideXlab platform.
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WEATHERING ANALYSIS OF Modified Poly (2,6-DIMETHYL-1,4-PHENYLENE ETHER) BY THERMAL ANALYSIS
Recent Advances in Environmentally Compatible Polymers, 2020Co-Authors: Y. Nishmoto, Yasutaka Nagai, Ken Ichi Sato, Fujio OhishiAbstract:ABSTRACT Weathering analysis of a Modified Poly (2,6-dimethyl-1,4-phenylene ether) using thermal analytical methods was studied. It was found that the evolution of CO2 and H2O was detected at the initial decomposition of degraded Modified PPE. We report the application of dynamic load TMA (DL-TMA) using compressive oscillating stress to the analysis of surface degradation of plastics. The results from the DL-TMA method have close relation with the molecular weight of the region of the surface. It was proved that the surface degradation is detectable with high sensitivity without any pretreatment by applying DL-TMA.
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Sensitive detection of degradation of Modified Poly(2,6-dimethyl-1,4-phenylene ether) by dynamic load thermomechanical analysis
Polymer Degradation and Stability, 2000Co-Authors: Yuko Nishimoto, Yasutaka Nagai, Ken Ichi Sato, Fujio OhishiAbstract:Weathering of a Modified Poly(2,6-dimethyl-1,4-phenylene ether) (m-PPE) was studied. It was found that the glass transition temperature or the complex modulus of the exposed sample in bulky state was almost the same as that of the unexposed sample. SEC, IR and TG-FT IR measurements proved that only the surface region of the exposed sample degraded. We report the application of dynamic load thermomechanical analysis (DL-TMA) using compressive oscillating load to the analysis of surface degradation of m-PPE. The results from the DL-TMA method have close relation with the molecular weight of the surface region. It was proved that the surface degradation is detectable in the bulk state with high sensitivity by applying DL-TMA.
