| Enzyme immobilization on ultrafine cellulose fibers via poly(acrylic acid) electrolyte grafts. | |
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MedLine Citation:
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PMID: 15816022 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
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Ultrafine cellulose fiber (diameter 200-400 nm) surfaces were grafted with polyacrylic acid (PAA) via either ceric ion initiated polymerization or methacrylation of cellulose with methacrylate chloride (MACl) and subsequent free-radical polymerization of acrylic acid. PAA grafts by ceric ion initiated polymerization increased with increasing reaction time (2-24 h), monomer (0.3-2.4 M), and initiator (1-10 mM) concentrations, and spanned a broad range from 5.5-850%. PAA grafts on the methacrylated cellulose fibers also increased with increasing molar ratios of MACl to cellulosic hydroxyl groups (MACl/OH, 2-6.4) and monomer acrylic acid (AA) to initiator potassium persulfate (KPS) ratios ([AA]/[KPS], 1.5-6), and were in a much narrower range between 12.8% and 29.4%. The adsorption of lipase (at 1 mg/ml lipase and pH 7) and the activity of adsorbed lipase (pH 8.5, 30 degrees C), in both cases decreased with increasing PAA grafts. The highest adsorption and activity of the lipase on the ceric ion initiated grafted fibers were 1.28 g/g PAA and 4.3 U/mg lipase, respectively, at the lowest grafting level of 5.5% PAA, whereas they were 0.33 g/g PAA and 7.1 U/mg lipase, respectively, at 12.8% PAA grafts on the methacrylated and grafted fibers. The properties of the grafted fibers and the absorption behavior and activity of lipase suggest that the PAA grafts are gel-like by ceric-initiated reaction and brush-like by methacrylation and polymerization. The adsorbed lipase on the ceric ion-initiated grafted surface possessed greatly improved organic solvent stability over the crude lipase. The adsorbed lipases exhibited 0.5 and 0.3 of the initial activity in the second and third assay cycles, respectively. |
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Authors:
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Hong Chen; You-Lo Hsieh |
Publication Detail:
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Type: Journal Article |
Journal Detail:
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Title: Biotechnology and bioengineering Volume: 90 ISSN: 0006-3592 ISO Abbreviation: Biotechnol. Bioeng. Publication Date: 2005 May |
Date Detail:
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Created Date: 2005-05-02 Completed Date: 2005-08-09 Revised Date: - |
Medline Journal Info:
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Nlm Unique ID: 7502021 Medline TA: Biotechnol Bioeng Country: United States |
Other Details:
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Languages: eng Pagination: 405-13 Citation Subset: IM |
Copyright Information:
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(c) 2004 Wiley Periodicals, Inc. |
Affiliation:
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Fiber and Polymer Science, University of California, Davis, CA 95616, USA. |
Export Citation:
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APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
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Acrylic Resins
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chemistry* Candida / enzymology Catalysis Cellulose / chemistry* Cerium / chemistry Enzymes, Immobilized / chemistry* Ions / chemistry Kinetics Lipase / chemistry Solvents |
| Chemical | |
Reg. No./Substance:
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0/Acrylic Resins; 0/Enzymes, Immobilized; 0/Ions; 0/Solvents; 7440-45-1/Cerium; 9003-01-4/carbopol 940; 9004-34-6/Cellulose; EC 3.1.1.3/Lipase |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
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