Label-free high-resolution infrared spectroscopy for spatiotemporal analysis of complex living systems

Gvazava, N.; Konings, S.; Cepeda-Prado, E.; Skoryk, V.; Umeano, C. H.; Dong, J.; Silva, I. A. N.; Rylander Ottosson, D.; Leigh, N. D.; Wagner, D. E.; Klementieva, O.

doi:10.1101/2023.01.05.522847

bioRxiv · 10.1101/2023.01.05.522847

Label-free high-resolution infrared spectroscopy for spatiotemporal analysis of complex living systems

Gvazava, N.·Konings, S.·Cepeda-Prado, E.·Skoryk, V.·Umeano, C. H.·Dong, J.·Silva, I. A. N.·Rylander Ottosson, D.·Leigh, N. D.·Wagner, D. E.·Klementieva, O.

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Abstract

Label-free chemical and structural imaging of complex living tissue and biological systems is the holy grail of biomedical research and clinical diagnostics. The current analysis techniques are time-consuming and/or require extensive sample preparation, often due to the presence of interfering molecules such as water, making them unsuitable for the analysis of such systems. Here, we demonstrate a proof-of-principle study using label-free optical photothermal mid-infrared microspectroscopy (O-PTIR) for fast, direct spatiotemporal chemical analysis of complex living biological systems at submicron resolution. While other analytical methods can provide only static snapshots of molecular structures, our O-PTIR approach enables time-resolved and in situ investigation of chemical and structural changes of diverse biomolecules in their native conditions. This comprises a technological breakthrough in infrared spectroscopy to analyze biomolecules under native conditions over time: in fresh unprocessed biopsies, living brain tissue, and vertebrates without compromising their viability. One-Sentence SummaryProof-of-principle application of non-destructive O-PTIR for high-resolution spatiotemporal chemical and structural analysis of unprocessed biopsies, living brain tissue, and vertebrates.

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Gvazava, N., Konings, S., Cepeda-Prado, E., Skoryk, V., Umeano, C. H., Dong, J., Silva, I. A. N., Rylander Ottosson, D., Leigh, N. D., Wagner, D. E., Klementieva, O.. 2023-01-05. Label-free high-resolution infrared spectroscopy for spatiotemporal analysis of complex living systems. https://doi.org/10.1101/2023.01.05.522847

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