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

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

Devetter, Brent M. ; Bhargava ; Rohit

关键词: surface-enhanced Raman spectroscopy;    gold nanoparticles;    plasmonics;    chemical sensing;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/44419/Brent_Devetter.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Surface-enhanced Raman spectroscopy (SERS) is an ultrasensitive technique with applicationsranging from in vitro and in vivo biological sensing to chemical and explosives detection. In thisthesis, we explore the design and characterization of suspensions of nanoparticles prior to theiruse for SERS-based molecular sensing. A major problem in SERS-based measurements is thatthe signals are often not interpreted quantitatively. Measurements performed in suspensionmimic the nanoprobe-to-nanoprobe optical interactions expected to be found in tissues withembedded nanoprobes while particle-level measurements of synthesized nanoparticles providethe molecular basis for calculations. We find that careful consideration of the localized surfaceplasmon resonance of SERS nanoprobes with respect to laser excitation wavelength is essentialfor maximizing detectable SERS signal. Additionally, the reporter molecule load per particledepends on synthesis conditions and the shape of the nanoparticles. Together, well-characterizedsuspensions can be used to understand the molecular and electromagnetic aspects of recordedSERS data.