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Atmospheric-pressure Molecular Imaging of Biological Tissues and Biofilms by LAESI Mass Spectrometry
Published on: September 3, 2010
Ambient Pressure Laser Desorption Ionization/Postphotoionization Mass Spectrometry Imaging
Xiaobo Yao1,2, Liutian Wu1, Yaya Wang1
1National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei230029, China.
Journal of the American Society for Mass Spectrometry
|July 21, 2026
Summary
A new ambient pressure laser desorption ionization with postphotoionization (AP-LDI/PI) method enables high-resolution imaging of metabolites in compact biological samples. This technique successfully mapped metabolites in mouse cerebellum and Ginkgo biloba tissues.
Area of Science:
- Analytical Chemistry
- Mass Spectrometry
- Biotechnology
Background:
- Postphotoionization enhances ionization efficiency in laser desorption ionization.
- Scanning compact and hard biological samples requires specialized techniques.
Purpose of the Study:
- To develop an ambient pressure laser desorption ionization with postphotoionization (AP-LDI/PI) assembly for front-side sample scanning.
- To investigate the effects of key parameters on AP-LDI/PI performance.
- To demonstrate the capability of AP-LDI/PI for high-resolution metabolite imaging in biological tissues.
Main Methods:
- Development of a compact AP-LDI/PI assembly operating in reflection mode.
- Optimization of laser energy, frequency, and stepper motor velocity.
- High-resolution mass spectrometry imaging of mouse cerebellum and Ginkgo biloba longitudinal sections.
Main Results:
- AP-LDI/PI successfully scanned mouse cerebellum slices with 10 μm spatial resolution in positive and negative ion modes.
- Longitudinal sections of Ginkgo biloba were imaged with 15 μm spatial resolution.
- Distinct spatial distributions of metabolites (ginkgo acids, choline, glutamate, ethoxycoumarin) in Ginkgo biloba were delineated.
Conclusions:
- AP-LDI/PI is an effective method for high-resolution, front-side imaging of metabolites in compact biological samples.
- The developed system offers significant potential for analyzing tissue microstructures and metabolite localization.
- This technique advances the capabilities of ambient pressure mass spectrometry for biological research.
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