2026-09-18T19:33:05Zhttps://dspace.mit.edu/server/oai/request

oai:dspace.mit.edu:1721.1/761232022-01-13T07:54:33Zcom_1721.1_7582com_1721.1_7581col_1721.1_131024

Alfredo Alexander-Katz. Moran, Stephanie E. (Stephanie Elizabeth) Massachusetts Institute of Technology. Dept. of Materials Science and Engineering. Massachusetts Institute of Technology. Department of Materials Science and Engineering 2013-01-07T21:22:47Z 2013-01-07T21:22:47Z 2012 2012 http://hdl.handle.net/1721.1/76123 821073257 Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2012. Cataloged from PDF version of thesis. Includes bibliographical references (p. 30-31). Biology has provided us with many organisms that are able to propel themselves through a fluid using cilia or flagella. This provides inspiration to create controllable systems that cannot only propel an organism or device through a fluid but can also create a fluid flow. Research has focused on how to mimic the mechanisms of these organisms for the use in microfluidic devices or drug delivery. This work examines walkers that are created using superparamagnetic beads placed in a rotating external magnetic field. Dipoles align in the beads so they assemble into rotors. These rotors follow the rotating magnetic field and are able to translate across a surface. This work looks at the effect of coating the beads and the surface with a polymer, Polyethylene Glycol(PEG). PEG has been shown to undergo a transition from an expanded state to a collapsed state under certain salt concentrations and temperature ranges. By looking at this transition we can see if the use of a polymer could affect the velocity of the rotors and if PEG could be used to control the velocity of the rotors or to initiate a transition. This transition is only seen by recording the velocity of the rotors, future research using other experimental procedures might be helpful in finalizing the transition of PEG in NaCl. It was unclear from these experiments whether the velocity of the rotors is dependent on the state of the polymer. by Stephanie E. Moran. S.B. 31 p. eng Massachusetts Institute of Technology M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 Materials Science and Engineering. Polymer coated superparamagnetic beads walking on polymer coated surface Thesis application/pdf false Publication unknown unknown <Publication xmlns="https://www.openaire.eu/cerif-profile/1.1/" id="63eda499-9403-435d-b21c-fbbcb90c6ddf"> <Type xmlns="https://www.openaire.eu/cerif-profile/vocab/COAR_Publication_Types">http://purl.org/coar/resource_type/c_1843</Type> <Language>eng</Language> <Title>Polymer coated superparamagnetic beads walking on polymer coated surface</Title> <PublishedIn> <Publication> </Publication> </PublishedIn> <PublicationDate>2012</PublicationDate> <Authors> <Author> <DisplayName>Moran, Stephanie E. (Stephanie Elizabeth)</DisplayName> <Affiliation> <OrgUnit> </OrgUnit> </Affiliation> </Author> </Authors> <Editors> </Editors> <Publishers> <Publisher> <DisplayName>Massachusetts Institute of Technology</DisplayName> <OrgUnit /> </Publisher> </Publishers> <License>http://dspace.mit.edu/handle/1721.1/7582</License> <Keyword>Materials Science and Engineering.</Keyword> <Abstract>Biology has provided us with many organisms that are able to propel themselves through a fluid using cilia or flagella. This provides inspiration to create controllable systems that cannot only propel an organism or device through a fluid but can also create a fluid flow. Research has focused on how to mimic the mechanisms of these organisms for the use in microfluidic devices or drug delivery. This work examines walkers that are created using superparamagnetic beads placed in a rotating external magnetic field. Dipoles align in the beads so they assemble into rotors. These rotors follow the rotating magnetic field and are able to translate across a surface. This work looks at the effect of coating the beads and the surface with a polymer, Polyethylene Glycol(PEG). PEG has been shown to undergo a transition from an expanded state to a collapsed state under certain salt concentrations and temperature ranges. By looking at this transition we can see if the use of a polymer could affect the velocity of the rotors and if PEG could be used to control the velocity of the rotors or to initiate a transition. This transition is only seen by recording the velocity of the rotors, future research using other experimental procedures might be helpful in finalizing the transition of PEG in NaCl. It was unclear from these experiments whether the velocity of the rotors is dependent on the state of the polymer.</Abstract> <Access xmlns="http://purl.org/coar/access_right" > </Access> </Publication>