Synthesis and characterization of nanoparticle suspensions: Towards quantitative surface-enhanced Raman spectroscopic sensing

Surface-enhanced Raman spectroscopy (SERS) is an ultrasensitive technique with applications ranging from in vitro and in vivo biological sensing to chemical and explosives detection. In this thesis, we explore the design and characterization of suspensions of nanoparticles prior to their use for SERS-based molecular sensing. A major problem in SERS-based measurements is that the signals are often not interpreted quantitatively. Measurements performed in suspension mimic the nanoprobe-to-nanoprobe optical interactions expected to be found in tissues with embedded nanoprobes while particle-level measurements of synthesized nanoparticles provide the molecular basis for calculations. We find that careful consideration of the localized surface plasmon resonance of SERS nanoprobes with respect to laser excitation wavelength is essential for maximizing detectable SERS signal. Additionally, the reporter molecule load per particle depends on synthesis conditions and the shape of the nanoparticles. Together, well-characterized suspensions can be used to understand the molecular and electromagnetic aspects of recorded SERS data.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Electrical & Computer Engr

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2013

Author dc:creator

• Devetter, Brent M.

Contributors dc:contributor

• Bhargava, Rohit

• surface-enhanced Raman spectroscopy
• gold nanoparticles
• plasmonics
• chemical sensing

Statement dc:rights

• Copyright 2013 Brent Devetter

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/44419

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/44419