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  • Metasurface-enhanced infrared spectroscopy for continuously monitoring the effect of cholesterol depletion in live cells
Title: Metasurface-enhanced infrared spectroscopy for continuously monitoring the effect of cholesterol depletion in live cells
Surface-enhanced infrared absorption (SEIRA) based on top-down fabricated nanostructures such as nanoantennas and metasurfaces has attracted much attention in recent years. These plasmonic resonant nanostructures can enhance the IR absorption signal of nearby molecules through its nearfield enhancement and have been shown to be able to detect adsorbed monolayers of proteins and lipids through their IR absorption spectra. Here, we demonstrate the continuous monitoring of cellular responses to stimuli using metasurface-enhanced infrared spectroscopy (MEIRS). A431 cells are seeded on a gold plasmonic metasurface fabricated on CaF2 substrate. Continuous monitoring is made possible by integrating the metasurface with a flow chamber, and the IR absorption spectra of the attached cells are measured in reflectance mode under continuous perfusion of cell culture medium. Scanning electron microscopy (SEM) revealed that the cells preferentially adhere to gold surfaces rather than CaF2 surfaces, suggesting that the IR signal measured through MEIRS is highly sensitive to the cells’ attachment and interaction with the gold metasurface. We have monitored the effect of methyl-beta-cyclodextrin, a cholesterol-depleting compound, on A431 cells. Principal component analysis highlighted the complex and subtle spectral changes of the cells. Keywords: MIR spectroscopy, surface-enhanced infrared absorption, metasurface, metasurface enhanced infrared absorption, MEIRS, cell adhesion, methyl-beta-cyclodextrin, cholesterol  more » « less
Award ID(s):
1719875
PAR ID:
10146282
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
SPIE BiOS, 2020 San Francisco, California, United States
Page Range / eLocation ID:
24
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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