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IR-MALDESI Mass Spectrometry Imaging at 50 Micron Spatial Resolution.

ABSTRACT: High spatial resolution in mass spectrometry imaging (MSI) is crucial to understanding the biology dictated by molecular distributions in complex tissue systems. Here, we present MSI using infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI) at 50 ?m resolution. An adjustable iris, beam expander, and an aspherical focusing lens were used to reduce tissue ablation diameters for MSI at high resolution. The laser beam caustic was modeled using laser ablation paper to calculate relevant laser beam characteristics. The minimum laser spot diameter on the tissue was determined using tissue staining and microscopy. Finally, the newly constructed optical system was used to image hen ovarian tissue with and without oversampling, detailing tissue features at 50 ?m resolution. Graphical Abstract ?.

SUBMITTER: Bokhart MT

PROVIDER: S-EPMC5693761 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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IR-MALDESI Mass Spectrometry Imaging at 50 Micron Spatial Resolution.

Bokhart Mark T MT Manni Jeffrey J Garrard Kenneth P KP Ekelöf Måns M Nazari Milad M Muddiman David C DC

Journal of the American Society for Mass Spectrometry 20170718 10

High spatial resolution in mass spectrometry imaging (MSI) is crucial to understanding the biology dictated by molecular distributions in complex tissue systems. Here, we present MSI using infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI) at 50 μm resolution. An adjustable iris, beam expander, and an aspherical focusing lens were used to reduce tissue ablation diameters for MSI at high resolution. The laser beam caustic was modeled using laser ablation paper to calcu ...[more]

PMID: 28721672

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