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bioRxiv · 10.1101/2022.06.24.497516

Single-shot Volumetric Chemical Imaging by Mid- Infrared Photothermal Fourier Light Field Microscopy

zhang, y.·Jia, D.·Yang, Q.·Xue, Y.·Tan, Y.·Guo, Z.·Zhang, M.·Tian, L.·Cheng, J.-X.
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Abstract

Three-dimensional molecular imaging of living organisms and cells plays a significant role in modern biology. Yet, current volumetric imaging modalities are largely fluorescence-based and thus lack chemical content information. Mid-infrared photothermal microscopy as a new chemical imaging technology provides infrared spectroscopic information at sub-micrometer spatial resolution. Here, by harnessing thermosensitive fluorescent dyes to sense the mid-infrared photothermal effect, we demonstrate mid-infrared photothermal Fourier light field (MIP-FLF) microscopy for single-shot volumetric infrared spectroscopic imaging at the speed of 8 volumes per second and sub-micron spatial resolution. Protein contents in bacteria and lipid droplets in living pancreatic cancer cells are visualized. Altered lipid metabolism in drug-resistant pancreatic cancer cells is observed with the MIP-FLF microscope.

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zhang, y., Jia, D., Yang, Q., Xue, Y., Tan, Y., Guo, Z., Zhang, M., Tian, L., Cheng, J.-X.. 2022-06-26. Single-shot Volumetric Chemical Imaging by Mid- Infrared Photothermal Fourier Light Field Microscopy. https://doi.org/10.1101/2022.06.24.497516

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