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bioRxiv · 10.1101/2021.06.30.450584

Monitoring the effects of chemical stimuli on live cells with metasurface-enhanced infrared reflection spectroscopy

Huang, S. H.·Li, J.·Fan, Z.·Delgado, R.·Shvets, G.
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Abstract

Infrared spectroscopy has found wide applications in the analysis of biological materials. A more recent development is the use of engineered nanostructures - plasmonic metasurfaces - as substrates for metasurface-enhanced infrared reflection spectroscopy (MEIRS). Here, we demonstrate that strong field enhancement from plasmonic metasurfaces enables the use of MEIRS as a highly informative analytic technique for real-time monitoring of cells. By exposing live cells cultured on a plasmonic metasurface to chemical compounds, we show that MEIRS can be used as a label-free phenotypic assay for detecting multiple cellular responses to external stimuli: changes in cell morphology, adhesion, lipid composition of the cellular membrane, as well as intracellular signaling. Using a focal plane array detection system, we show that MEIRS also enables spectro-chemical imaging at the single-cell level. The described metasurface-based all-optical sensor opens the way to a scalable, high-throughput spectroscopic assay for live cells.

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Huang, S. H., Li, J., Fan, Z., Delgado, R., Shvets, G.. 2021-07-01. Monitoring the effects of chemical stimuli on live cells with metasurface-enhanced infrared reflection spectroscopy. https://doi.org/10.1101/2021.06.30.450584

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