Show simple item record

dc.contributor.advisor​Willson, C. Grant, 1939-
dc.creatorTang, Hao, 1985-en
dc.date.accessioned2013-11-07T21:45:45Zen
dc.date.issued2012-12en
dc.date.submittedDecember 2012en
dc.identifier.urihttp://hdl.handle.net/2152/22061en
dc.descriptiontexten
dc.description.abstractSelf-assembly provides an efficient way to build complex structures with great flexibility in terms of components and properties. This dissertation presents two different forms of self-assembly for technical applications. The first example is the molecular assembly of liquid crystals (LCs). Attaching appropriate side chains on anthracene, oligothiophene, and oligoarenethiophene successfully constructed liquid crystalline organic semiconductors. The phase transitions of the LC semiconductors were analyzed by differential scanning calorimetry (DSC) and polarized optical microscopy (POM). The effect of the LC phase change on charge transport was probed by the space-charge limited current (SCLC) method and the field-effect transistor (FET) method. Mobility in the LC phase rose in anthracenyl esters but decreased in oligothiophenes and oligoarenethiophenes. The different electronic behavior of LC semiconductors may be caused by the difference in domain size and/or the difference in response to electric field. The second example of self-assembly in this dissertation is DNA-guided self-assembly of micrometer-sized particles. Patternable bioconjugation polymers were synthesized to allow for lithographic patterning and DNA conjugation. The base pairing of DNA was then used to drive the self-assembly of DNA-conjugated particles. The DNA conjugation chemistry was studied in detail using a fluorescence-based reaction test platform. The conjugated DNA on the polymer surface retained its ability to hybridize with its complement and was efficient in binding microspheres with complementary strands. Highly specific bead-to-bead assembly was analyzed using imaging flow cytometry, and the fractions of self-assembly products were explained on the basis of chemical equilibrium. The process of particle fabrication using photolithography was successfully developed, and the self-assembly of lithographically-patterned particles was demonstrated. We envision that the technologies described in this dissertation will be useful in a variety of fields ranging from microelectronics to biotechnology.en
dc.format.mimetypeapplication/pdfen
dc.language.isoen_USen
dc.subjectSelf-assemblyen
dc.subjectLiquid crystalsen
dc.subjectDNAen
dc.subjectLithographyen
dc.titleApplications of self-assembly : liquid crystalline semiconductors and DNA-conjugated microparticlesen
dc.date.updated2013-11-07T21:45:45Zen
dc.description.departmentChemical Engineeringen
thesis.degree.departmentChemical Engineeringen
thesis.degree.disciplineChemical Engineeringen
thesis.degree.grantorThe University of Texas at Austinen
thesis.degree.levelDoctoralen
thesis.degree.nameDoctor of Philosophyen
dc.embargo.terms12/1/2013en
dc.embargo.lift12/1/2013en


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record