Friday, October 6, 2017 at 2:30pm to 3:30pm
For our next seminar, we welcome Dr. Gennady Shvets, Professor of Applied and Engineering Physics from Cornell University.
"Metasurface-Enhanced Infrared Reflection Spectroscopy: From Protein Detection to Cells Differentiation"
ABSTRACT: The ability to distinguish between different states of a given cell, as well as between different types of cells, is crucial for a variety of fundamental and clinical life sciences applications. Those include: monitoring of biochemical processes in a living cell, effective early cancer screening, detection of the effects of cancer therapeutics on cancer cells, to name just a few. The most common approach to differentiating between different cell types is immunological. However, the specificity of such approaches is limited because different cell types may over-express the same molecules. Therefore, there is considerable interest in label-free approaches to differentiating the cells that rely entirely on their native biochemical properties.
One such approach is infrared spectroscopic cytology based on the quantification of vibrational fingerprints of cell’s constituent molecules. I will describe a new experimental technique developed in our lab, Metasurface-Enhanced Infrared Reflection Spectroscopy (MEIRS), used to interrogating the chemical composition of cellular membranes. MEIRS relies on the nano-bio interface between plasmonic nanostructures and the cells (or tissues) to probe the outer region of the cell that is in the more intimate contact with the metasurface than the rest of the cell. Because the localization depth of the field evanescent optical field, which is tens of nanometers, is comparable to the thickness of the cellular membrane, we are utilizing the strong enhancement of the mid-infrared optical fields to interrogate the chemical composition of the membrane. I will present several early successes of the technique: (a) the ability to distinguish between cancerous and normal cells using standard (immortal) cell line models, (b) first spectroscopic differentiation between gram-positive and gram-negative bacteria, and (c) spectroscopic detection of the effects of co-administered cancer therapeutics that overcome multi-drug resistance in animal models. The prospects for using MEIRS for “liquid biopsy” of metastatic cancer, for drug screening in the context of personalized medicine, and for in vivo detection of tumor margins, will be discussed at the end.
BIO: Gennady Shvets is a Professor of Applied and Engineering Physics at Cornell University. He was on the physics faculty at the University of Texas at Austin between 2004 and 2016. Dr. Shvets received his PhD in Physics from MIT in 1995. His research interests include nanophotonics, optical and microwave metamaterials and their applications, such as biomedical sensing and novel optoelectronic devices. He is a Fellow of the American Physical Society and the Optical Society of America. His most recent work deals with the applications of metamaterials and plasmonics to infrared light generation and harvesting, concentrated solar energy and thermo-photovoltaic systems, biosensing and molecular fingerprinting of proteins and live cells using metamaterial arrays. He is particularly interested in the integration of metamaterials and metasurfaces with various applications-specific platforms such as microfluidics and optical fibers. His group is exploring the bio-nano interface between plasmonic structrures and cells, tissues, and bacterial colonies. The ultimate goal is to develop a label-free rapid spectroscopic technique that will differentiate between different cells types, both ex vivo and, eventually, in vivo.