Nanomaterials: Synthesis, Characterization, and their Bio-Integration

Nanomaterials: Synthesis, Characterization, and their Bio-IntegrationTitle page for ETD etd-01242006-180801

Type of DocumentDissertation

AuthorJennings, Travis L

Author's Email Addresstjennings@penguinsmack.com

URNetd-01242006-180801

TitleNanomaterials: Synthesis, Characterization, and their Bio-Integration

DegreePhD

DepartmentChemistry and Biochemistry, Department of

Advisory CommitteeAdvisor Name

Title

Geoffrey Strouse

Committee Chair

Bryant Chase

Committee Member

Harold Kroto

Committee Member

Michael Kasha

Committee Member

Keywords Quantum Dot

FRET

energy transfer

nanoparticle

nanomaterial

Date of Defense2006-01-18

Availabilityunrestricted

Abstract

The purpose of this dissertation is to utilize the changing optical and electronic properties of

metallic and semiconductor nanomaterials for applications to biotechnology. The dynamic

optical properties of metals and semiconductors with size is discussed in regard to the ability

of these materials to accept electronic excitation energy from classical molecular fluorescent

dyes (Chap. 2). Absorption, photoluminescence, and time-resolved photoluminescence

experiments are performed on metal nanoparticle-dye pairs at separation distances controlled

via synthetic DNA spacers where the distance, dye, and nanoparticle size are varied (Chaps.

3 and 4). It is found that the efficiency of energy transfer to small metal nanoparticles is

greater than expected for a 1/R^6 Frster mechanism of energy transfer and the measurable

separation distance is increased, following a 1/R^4 dependence. The 1/R^4 distance dependence

is the theoretically established relationship of an excited molecule to a metallic surface. This

tool, termed Nanometal Surface Energy Transfer (NSET) is then used in Chapters 5 and 6

to measure the kinetics and conformational changes associated with a hammerhead ribozyme

as a model test subject for NSET methodology. Finally, ZnS-overcoated CdSe semiconductor

quantum dots, (Chap. 7) are synthesized controllably and characterized in terms of their

potential for biological incorporation for detection or in vitro studies.