Chemistry Seminar Series: Gregory Wallace

Dr. Gregory Wallace    
Research Associate
University of Strathclyde
Glasgow, Scotland

Thursday, January 26, 2023
1:30 p.m.

In-person: C2- 361 (Reading Room) and Online via MS Teams 

Abstract: Surface-enhanced spectroscopies have emerged as new analytical techniques for the qualitative and quantitative detection of analytes. By coupling the unique vibrational fingerprints obtained by Raman and infrared spectroscopies with the strong enhancements offered by plasmonic nanostructures (Figure 1), it is possible to push the limits of detection. Of note is surface-enhanced Raman scattering (SERS), where many have argued that single-molecule detection can be observed.1 SERS has also shown great promise as a bioanalytical technique for detection within complex biological environments, such as cells and tissues.2 This seminar reviews my recent endeavours in the use of plasmonic nanostructures for surface-enhanced spectroscopies, and in my proposed independent research.

The first portion of the talk will cover the use of hollow metallic nanoshells for photothermal therapy and SERS. Interestingly, we have observed that the optical properties of these nanoparticles change under photothermal irradiation. I will discuss our recent efforts to better understand the causes of these phenomena. The second part of my presentation will explore the SERS sensing capabilities of plasmonic nanofibers. An emphasis is placed on the developed blueprint for performing these types of measurements in ex vivo brain tissue slices.3 Finally, I will introduce my short through long-term research goals centered around the detection of chiral analytes using surface-enhanced spectroscopies.

Figure 1. A) SEM image of lithographically prepared superimposed gold nanoprisms.4 B) TEM image of hollow metallic nanoshells. C) SEM image of a plasmonic nanofiber decorated with two different types of gold nanoparticles.

1. Wallace, G.Q.; Graham, D. Nat. Rev. Chem., 2022, 6, 842-843.
2. Wallace, G.Q.; Masson, J.-F. Analyst, 2020, 145, 7162-7185.
3. Wallace, G.Q.; et al. J. Chem. Phys., 2020, 153, 124702.
4. Wallace, G.Q.; et al. ACS Photonics, 2016, 3, 1723-1732