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dc.contributor.authorMejia-Ariza, Raquelen_US
dc.date.accessioned2014-03-14T21:48:54Z
dc.date.available2014-03-14T21:48:54Z
dc.date.issued2010-10-18en_US
dc.identifier.otheretd-11012010-115420en_US
dc.identifier.urihttp://hdl.handle.net/10919/45432
dc.description.abstractSuperparamagnetic nanoparticles have potential applications in targeted drug delivery and as magnetic resonance imaging contrast agents. Magnetite clusters are of particular interest for these applications because they provide higher magnetic flux (under a magnetic field) than individual magnetite nanoparticles, are biocompatible, and their size and compositions can be controlled. This thesis involves the controlled synthesis and characterization of clusters composed of magnetite nanoparticles stabilized with an amphiphilic block copolymer. It outlines a method to design and form well-defined and colloidally stable magnetite clusters. A Multi Inlet Vortex mixer (MIVM) was used because it is a continuous process that yields particles with relatively narrow and controlled size distributions. In the MIVM, four liquid streams collide under turbulent conditions in the mixing chamber where clusters form within milliseconds. The formation of magnetite clusters was studied in the presence of amphiphilic block copolymers containing poly (ethylene oxide) to provide steric stabilization and control of size distributions using flash nanoprecipitation. First, the mixer was tested using β-carotene as a model compound to form nanoparticles stabilized with an amphiphilic triblock copolymer poly(propylene oxide)-b-poly(ethylene oxide) (F127) at different Reynolds numbers and supersaturation values. Size analysis was done using dynamic light scattering and nanoparticle tracking analysis techniques. The cluster structure was studied using electron microscopy and magnetite compositions were measured using thermogravimetric analysis. Finally, the stability of magnetite clusters was studied over time and the effect of an applied magnetite field on the colloidal stability was investigated.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartMejia-Ariza_Raquel_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 (propylene oxide)en_US
dc.subjectsteric stabilizationen_US
dc.subjectcontrast agenten_US
dc.subjectRapid nanoprecipitationen_US
dc.subjectMulti Inlet Vortex Mixeren_US
dc.subjectmagnetite clustersen_US
dc.subjectpoly (ethylene oxide)en_US
dc.titleDesign, Synthesis, and Characterization of Magnetite Clusters using a Multi Inlet Vortex Mixeren_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.committeechairDavis, Richey M.en_US
dc.contributor.committeememberEdgar, Kevin J.en_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-11012010-115420/en_US
dc.contributor.committeecochairRiffle, Judy S.en_US
dc.date.sdate2010-11-01en_US
dc.date.rdate2010-11-17
dc.date.adate2010-11-17en_US


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