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dc.contributor.authorHull, Matthew Scotten_US
dc.date.accessioned2017-04-06T15:43:38Z
dc.date.available2017-04-06T15:43:38Z
dc.date.issued2011-08-11en_US
dc.identifier.otheretd-09072011-225305en_US
dc.identifier.urihttp://hdl.handle.net/10919/77192
dc.description.abstractMetallic nanoparticles (MetNPs) with unique nanoscale properties, including novel optical behavior and superparamagnetism, are continually being developed for biomedical and industrial applications. In certain biomedical applications where extended blood half-lives are required, MetNPs are surface-functionalized using polymers, proteins, and other stabilizing agents to facilitate their resistance to salt-induced aggregation. Given their colloidal stability in high ionic-strength matrices, functionalized MetNPs are anticipated to be persistent aquatic contaminants. Despite their potential environmental significance, the persistence of surface- functionalized MetNPs as individually-stabilized nanoparticles in aquatic environments is largely unknown. Further, few studies have investigated the fundamental factors that influence MetNP uptake and fate/transport processes in ecologically susceptible aquatic biota, such as filter- feeding bivalves, which ingest and accumulate a broad range of dissolved- and particulate-phase contaminants. The present study describes a comprehensive approach to prepare and rigorously characterize MetNP test suspensions to facilitate fundamental examinations of nanoparticle uptake and fate/transport processes in freshwater and marine bivalves. We demonstrate the importance of accurately characterizing test suspensions in order to better understand MetNP persistence as individually-stabilized nanoparticles within aquatic test media, and define an optical-activity metric suitable for quantifying and comparing the persistence of variable MetNP formulations as National Nanotechnology Initiative (NNI) definable nanoscale materials. We also show that individually-stabilized MetNPs of variable elemental composition, particle diameter, and surface coating are accessible to bivalves in both freshwater and marine environments. Clearance rates for MetNPs are positively related to the diameter and initial concentration of MetNP suspensions. The observed size-dependence of particle filtration rates facilitates ‘size-selective biopurification' of particle suspensions with nanoscale resolution, and may have applicability in future sustainable nanomanufacturing processes. Filtered MetNPs are retained for extended periods post-exposure primarily within the bivalve digestive tract and digestive gland, but migration to other organ systems was not observed. Clusters of MetNPs were recovered in concentrated form from excreted feces, suggesting that biotransformation and biodeposition processes will play an important role in transferring MetNPs from the water column to benthic environments.
dc.language.isoen_USen_US
dc.publisherVirginia Techen_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.subjectfate and transporten_US
dc.subjectpersistenceen_US
dc.subjectaquatic biotaen_US
dc.subjectfilter-feedersen_US
dc.subjectnanotechnologyen_US
dc.subjectnanomaterialsen_US
dc.subjectiron nanoparticlesen_US
dc.subjectgold nanoparticlesen_US
dc.subjectCorbicula flumineaen_US
dc.subjectquantum dotsen_US
dc.titleFactors influencing the uptake and fate of metallic nanoparticles in filter-feeding bivalvesen_US
dc.typeDissertationen_US
dc.contributor.departmentEnvironmental Engineeringen_US
dc.description.degreePh. D.en_US
thesis.degree.namePh. D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
thesis.degree.disciplineEnvironmental Engineeringen_US
dc.contributor.committeechairVikesland, Peter J.en_US
dc.contributor.committeememberSchreiber, Madeline E.en_US
dc.contributor.committeememberMarr, Linsey C.en_US
dc.contributor.committeememberHochella, Michael F. Jr.en_US
dc.type.dcmitypeTexten_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-09072011-225305/en_US
dc.contributor.committeecochairLove, Nancy C.en_US
dc.date.sdate2011-09-07en_US
dc.date.rdate2016-09-30
dc.date.adate2011-09-22en_US


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