Nanoplasmonic Sensors for Chemical and Bioanalysis

Nov 14

Thursday, November 14, 2024

10:45 am – 12:15 pm

Presenter: Dr. Li-Lin Tay, Principal Research Officer and Team Lead, Metrology Research Council Canada (NRC)

Plasmonic nanostructures exhibit extraordinary optical properties due to their resonant interaction with light. When coupled, they behave as optical antennas, focusing electromagnetic fields to enable surface enhanced spectroscopies, with the best-known example being surface-enhanced Raman scattering (SERS). SERS sensors are an attractive option for trace chemical detection and high sensitivity biochemical analysis.

This presentation will focus on our work in developing various SERS sensors for bio- and chemical analysis. I will discuss our recent work in the fabrication of paper-based SERS sensors through inkjet-printing of colloidal Au nanoparticles onto a paper substrate. These flexible and porous paper-based SERS sensors offers the additional advantage of point-of-sampling usage, which rigid SERS sensors cannot provide. I will also briefly discuss the design strategy of SERS nanotags and their applications in bioanalysis.

The development of new SERS sensors is an active and vibrant research field, leading to a wide range of nanostructure designs with varying performances. Commercial SERS substrates, used with handheld Raman analyzers, promise the detection of environmental and industrial toxins, narcotics and warfare agents and have reached the end-user market. Conventionally, the SERS Enhancement Factor (EF) has been used to benchmark the performance of different SERS sensors. However, accurately determining the EF of SERS sensors is challenging. In the second part of this presentation, I will discuss the ongoing efforts by National Metrology Institutes around the world to establish alternative benchmarks for inter-comparability of SERS sensors and to develop methodologies for traceable quantitative analysis.

Dr. Li-Lin Tay

Li-Lin Tay is a Principal Research Officer and Team Lead in the Metrology Research Centre at the National Research Council Canada (NRC). She holds a B.Sc. in Physics and Ph.D. in Physical Chemistry, both from University of Toronto. She joined the NRC in 2002 and led the research effort on light scattering of quantum confined semiconductor devices. Since 2012, she has focused her research on the optical properties of plasmonic nanostructures, surface enhanced Raman scattering (SERS) sensors for field detection of chemical agents and bioanalysis, and Raman metrology.  She has published over 90 peer reviewed publications, three book chapters and 17 technical reports. She also leads her team in the development of the state-of-the-art optical radiation measurement and advanced optical spectroscopies in support of Canada’s commitment to the Mutual Recognition Arrangement in the international committee on Weights and Measures (CIPM-MRA). Her team is responsible for the realization and dissemination of a broad range of photometry, spectrophotometry and infrared radiometry measurements.