Dissertations, Theses, and Capstone Projects

Date of Degree

2-2016

Document Type

Dissertation

Degree Name

Ph.D.

Program

Chemistry

Advisor

Charles Michael Drain

Advisor

Moritz F. Kircher

Committee Members

John Lombardi

Stephen O'Brien

Jason Lewis

Subject Categories

Chemistry | Materials Chemistry | Nanotechnology | Radiochemistry

Keywords

Nucleation Theory, Crystal Growth, Surface-Enhanced Raman Scattering, Gold, Silica, Cancer Imaging

Abstract

Surface-enhanced Raman scattering (SERS) nanoparticles are exciting candidates for high-precision cancer imaging due to their highly specific spectral signature (Raman “fingerprint”) and propensity for passive targeting of cancerous tissues. However, the signal intensity of currently available SERS nanoparticles is insufficient for cancer imaging via passive targeting in most solid tumors. The overarching aim of this body of work is to develop a new generation of SERS nanoparticles with sufficiently low limits of detection to enable robust detection of various solid tumors in vivo.

The complexity of SERS nanoparticles requires significant advances to the theoretical and experimental understanding of metal nanoparticle syntheses and the methods of their encapsulation if optimized constructs are to be achieved. In particular, the requirement that the Raman-active molecules adsorb to the metal nanoparticle for maximum surface enhancement necessitates nucleation, growth and encapsulation methods that maximize the potential for metal-molecule binding. This poses a substantial roadblock to overcoming the current limitations of SERS nanoparticle intensity, because metal nanoparticle syntheses rely upon surface-passivating surfactants or polymers to enable morphological control. Moreover, metal nanoparticles typically require priming of their surface with silicate or polymer layers to ensure successful encapsulation under high ionic strength (e.g., from the presence of Raman-active molecules and counterions). These challenges make the optimization of SERS nanoparticles a case study in the theoretical and experimental frontiers of nanoparticle engineering.

Share

COinS