The Experts below are selected from a list of 56268 Experts worldwide ranked by ideXlab platform
Mark R Etzel - One of the best experts on this subject based on the ideXlab platform.
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design of salt tolerant membrane adsorbers for viral clearance
Biotechnology and Bioengineering, 2009Co-Authors: William Riorda, Ku Orso, Steve Heilma, Kanna Seshadri, Mark R EtzelAbstract:Strong anion Exchange chromatography has frequently been employed as a viral clearance step during downstream processing of biological therapeutics. When challenged with viruses having only slightly acidic isoelectric points, the performance of the anion Exchange Operation becomes highly dependent on the buffer salt concentration, with the virus log reduction value (LRV) dropping dramatically in buffers with 50–150 mM salt. In this work, a series of anion Exchange membrane adsorbers utilizing alternative ligand chemistries instead of the traditional quaternary amine (Q) ligand have been developed that overcome this limitation. Four different ligands (agmatine, tris-2-aminoethyl amine, polyhexamethylene biguanide, and polyethyleneimine) achieved >5 LRV of bacteriophage ΦX174 (pI ∼ 6.7) at pH 7.5 and up to 150 mM salt, compared to 0 LRV for the Q ligand. By evaluating structural derivatives of the successful ligands, three factors were identified that contributed to ligand salt tolerance: ligand net charge, ligand immobilization density on the membrane, and molecular structure of the ligand-binding group. Based on the results of this study, membrane adsorbers that incorporate alternative ligands provide a more robust and salt tolerant viral clearance-processing step compared to traditional strong anion Exchange membrane adsorbers. Biotechnol. Bioeng. 2009;103: 920–929. © 2009 Wiley Periodicals, Inc.
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design of salt tolerant membrane adsorbers for viral clearance
Biotechnology and Bioengineering, 2009Co-Authors: William Riordan, Steve Heilmann, Kurt Brorson, Kannan Seshadri, Mark R EtzelAbstract:Strong anion Exchange chromatography has frequently been employed as a viral clearance step during downstream processing of biological therapeutics. When challenged with viruses having only slightly acidic isoelectric points, the performance of the anion Exchange Operation becomes highly dependent on the buffer salt concentration, with the virus log reduction value (LRV) dropping dramatically in buffers with 50-150 mM salt. In this work, a series of anion Exchange membrane adsorbers utilizing alternative ligand chemistries instead of the traditional quaternary amine (Q) ligand have been developed that overcome this limitation. Four different ligands (agmatine, tris-2-aminoethyl amine, polyhexamethylene biguanide, and polyethyleneimine) achieved >5 LRV of bacteriophage PhiX174 (pI approximately 6.7) at pH 7.5 and up to 150 mM salt, compared to 0 LRV for the Q ligand. By evaluating structural derivatives of the successful ligands, three factors were identified that contributed to ligand salt tolerance: ligand net charge, ligand immobilization density on the membrane, and molecular structure of the ligand-binding group. Based on the results of this study, membrane adsorbers that incorporate alternative ligands provide a more robust and salt tolerant viral clearance-processing step compared to traditional strong anion Exchange membrane adsorbers.
Kentaro Kyuno - One of the best experts on this subject based on the ideXlab platform.
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low temperature 330 c crystallization and dopant activation of ge thin films via agsb induced layer Exchange Operation of an n channel polycrystalline ge thin film transistor
Applied Physics Express, 2017Co-Authors: Tatsuya Suzuki, Benedict Mutunga Joseph, Misato Fukai, Masao Kamiko, Kentaro KyunoAbstract:Ge thin films have been prepared by layer-Exchange metal-induced crystallization using AgSb alloy as a catalyst. Not only the crystallization of Ge, but also the incorporation of Sb atoms into the crystalline Ge layer and their activation have been realized during the process at a temperature as low as 330 °C. Thin-film transistors have been fabricated using the Ge thin films as channel layers and the Operation of an n-channel transistor with an on/off ratio of over 300 has been demonstrated.
Tatsuya Suzuki - One of the best experts on this subject based on the ideXlab platform.
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low temperature 330 c crystallization and dopant activation of ge thin films via agsb induced layer Exchange Operation of an n channel polycrystalline ge thin film transistor
Applied Physics Express, 2017Co-Authors: Tatsuya Suzuki, Benedict Mutunga Joseph, Misato Fukai, Masao Kamiko, Kentaro KyunoAbstract:Ge thin films have been prepared by layer-Exchange metal-induced crystallization using AgSb alloy as a catalyst. Not only the crystallization of Ge, but also the incorporation of Sb atoms into the crystalline Ge layer and their activation have been realized during the process at a temperature as low as 330 °C. Thin-film transistors have been fabricated using the Ge thin films as channel layers and the Operation of an n-channel transistor with an on/off ratio of over 300 has been demonstrated.
Nanrun Zhou - One of the best experts on this subject based on the ideXlab platform.
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bit level quantum color image encryption scheme with quantum cross Exchange Operation and hyper chaotic system
Quantum Information Processing, 2018Co-Authors: Nanrun Zhou, Weiwei Chen, Yunqian WangAbstract:In order to obtain higher encryption efficiency, a bit-level quantum color image encryption scheme by exploiting quantum cross-Exchange Operation and a 5D hyper-chaotic system is designed. Additionally, to enhance the scrambling effect, the quantum channel swapping Operation is employed to swap the gray values of corresponding pixels. The proposed color image encryption algorithm has larger key space and higher security since the 5D hyper-chaotic system has more complex dynamic behavior, better randomness and unpredictability than those based on low-dimensional hyper-chaotic systems. Simulations and theoretical analyses demonstrate that the presented bit-level quantum color image encryption scheme outperforms its classical counterparts in efficiency and security.
William Riordan - One of the best experts on this subject based on the ideXlab platform.
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design of salt tolerant membrane adsorbers for viral clearance
Biotechnology and Bioengineering, 2009Co-Authors: William Riordan, Steve Heilmann, Kurt Brorson, Kannan Seshadri, Mark R EtzelAbstract:Strong anion Exchange chromatography has frequently been employed as a viral clearance step during downstream processing of biological therapeutics. When challenged with viruses having only slightly acidic isoelectric points, the performance of the anion Exchange Operation becomes highly dependent on the buffer salt concentration, with the virus log reduction value (LRV) dropping dramatically in buffers with 50-150 mM salt. In this work, a series of anion Exchange membrane adsorbers utilizing alternative ligand chemistries instead of the traditional quaternary amine (Q) ligand have been developed that overcome this limitation. Four different ligands (agmatine, tris-2-aminoethyl amine, polyhexamethylene biguanide, and polyethyleneimine) achieved >5 LRV of bacteriophage PhiX174 (pI approximately 6.7) at pH 7.5 and up to 150 mM salt, compared to 0 LRV for the Q ligand. By evaluating structural derivatives of the successful ligands, three factors were identified that contributed to ligand salt tolerance: ligand net charge, ligand immobilization density on the membrane, and molecular structure of the ligand-binding group. Based on the results of this study, membrane adsorbers that incorporate alternative ligands provide a more robust and salt tolerant viral clearance-processing step compared to traditional strong anion Exchange membrane adsorbers.
