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bioRxiv · 10.1101/2023.05.07.539107

RaMALDI: enabling simultaneous Raman and MALDI imaging of the same tissue section

Yang, E.·Kim, J. H.·Tressler, C. M.·Shen, X. E.·Brown, D. R.·Johnson, C. C.·Barman, I.·Glunde, K.
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Abstract

Multimodal tissue imaging techniques that integrate two complementary modalities are powerful discovery tools for unraveling biological processes and identifying biomarkers of disease. Combining Raman spectroscopic imaging (RSI) and matrix-assisted laser-desorption/ionization (MALDI) mass spectrometry imaging (MSI) to obtain fused images with the advantages of both modalities has the potential of providing spatially resolved, sensitive, and specific biomolecular information, but has so far involved two separate, consecutive tissue sections for RSI and MALDI MSI, resulting in images from two separate entities with inherent disparities. We have developed RaMALDI, a streamlined, integrated, multimodal imaging workflow of RSI and MALDI MSI, performed on a single tissue section with one sample preparation protocol. We show that RaMALDI imaging of various tissues effectively integrates molecular information acquired from both RSI and MALDI MSI of the same sample. Table of Contents O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=142 SRC="FIGDIR/small/539107v1_ufig1.gif" ALT="Figure 1"> View larger version (26K): org.highwire.dtl.DTLVardef@1829ccaorg.highwire.dtl.DTLVardef@3d018org.highwire.dtl.DTLVardef@531015org.highwire.dtl.DTLVardef@144f1a3_HPS_FORMAT_FIGEXP M_FIG C_FIG We demonstrate for the first time RaMALDI imaging, a streamlined, integrated multimodal imaging workflow of Raman spectroscopy imaging (RSI) and matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI), which is performed on a single sample and uses one sample preparation protocol. RaMALDI imaging of various tissues effectively integrates molecular information acquired from both RSI and MALDI MSI of the same sample.

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Yang, E., Kim, J. H., Tressler, C. M., Shen, X. E., Brown, D. R., Johnson, C. C., Barman, I., Glunde, K.. 2023-05-07. RaMALDI: enabling simultaneous Raman and MALDI imaging of the same tissue section. https://doi.org/10.1101/2023.05.07.539107

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