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dc.contributor.authorCarmichael-Baranauskas, Anita Yvonneen_US
dc.date.accessioned2014-03-14T20:33:45Z
dc.date.available2014-03-14T20:33:45Z
dc.date.issued2010-04-01en_US
dc.identifier.otheretd-04162010-143440en_US
dc.identifier.urihttp://hdl.handle.net/10919/31737
dc.description.abstractThe research presented in this thesis focuses on the synthesis of three amphiphilic block copolymer systems containing poly(ethylene oxide) (PEO) blocks. The polymer systems were developed for use in biomedical applications. The first of these is a series of poly(ethylene oxide-b¬-oxazoline) (PEO-b-POX) diblock copolymers for use in the progress towards novel non-viral gene transfer vectors. Poly(ethylene oxide-b¬-2-ethyl-2-oxazoline) (PEO-b-PEOX) and poly(ethylene oxide-b¬-2-methyl-2-oxazoline) (PEO-b-PMOX) were investigated. The PEOX block was hydrolyzed with acid to form linear polyethylenimine (L-PEI). The polycation L-PEI is well known for its DNA binding efficiency but the water solubility of the resulting DNA/polymer complex is limited. Addition of a PEO block is directed towards the formation of a water dispersible DNA/copolymer complex. Dynamic light scattering of the PEO-b-PEOX and PEO-b-PEI block copolymers indicated that both systems existed as single chains in aqueous solution at pH 7. PEO copolymers also play a significant role in the formation of magnetic magnetite nanoparticles, which are dispersible in water at biological pH (pH =7). There is significant interest in the design of magnetic nanoparticle fluids for biomedical applications including magnetic field-directed drug delivery, magnetic cell separations, and blood purification. For use in vivo, the magnetite nanoparticles must be coated with biocompatible materials. Such polymers render the nanoparticles dispersible in water. Harris1 et al. synthesized PEO based, polyurethane triblocks with pendant carboxylic acid groups for use in formation of stable aqueous magnetic fluids. Building from this work, two polyurethane and polyurethaneurea systems were synthesized with 1300 g/mol PEOX and 2500 g/mol and PEOX2070 g/mol poly(ethylene oxide-co-propylene oxide) tailblocks, respectively. The PEO/PPO random copolymer contained about 25 weight percent PPO, and this disrupted the capacity of the PEO to crystallize. The PEOX based urethane triblocks were synthesized through reacting the tailblocks with the monomers for the center block whereas the PEO/PPO based polyurethaneurea was synthesized through forming the central urethane block with pendant acid groups first and then terminating the copolymer with the monofunctional copolymer. Terminal amine groups on the PEO/PPO tailblock afforded a triblock linked with two urea groups. The new polyurethanes with the PEOX tailblocks and the new polyurethaneurea with the PEO/PPO tailblocks could be utilized to efficiently stabilize magnetite nanoparticles in water.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartCarmichael_AYGC_T_2010.pdfen_US
dc.rightsI hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Virginia Tech or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.en_US
dc.subjectPoly(2-ethyl-2-oxazoline)en_US
dc.subjectMagnetiteen_US
dc.subjectNanoparticlesen_US
dc.subjectPolyethylenimineen_US
dc.subjectPoly(ethylene oxide)en_US
dc.titleSynthesis of Amphiphilic Block Copolymers for Use in Biomedical Applicationsen_US
dc.typeThesisen_US
dc.contributor.departmentMacromolecular Science and Engineeringen_US
dc.description.degreeMaster of Scienceen_US
thesis.degree.nameMaster of Scienceen_US
thesis.degree.levelmastersen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
thesis.degree.disciplineMacromolecular Science and Engineeringen_US
dc.contributor.committeechairRiffle, Judy S.en_US
dc.contributor.committeememberDavis, Richey M.en_US
dc.contributor.committeememberMcGrath, James E.en_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-04162010-143440/en_US
dc.date.sdate2010-04-16en_US
dc.date.rdate2012-06-22
dc.date.adate2010-06-16en_US


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