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06:21
Imaging of Biological Tissues by Desorption Electrospray Ionization Mass Spectrometry
Published on: July 12, 2013
Ambient molecular imaging by desorption electrospray ionization mass spectrometry
Justin M Wiseman1, Demian R Ifa, Andre Venter
1Department of Chemistry, Purdue University, West Lafayette, Indiana, USA.
Nature Protocols
|March 8, 2008
Summary
Desorption electrospray ionization (DESI) enables direct ambient analysis of biological tissues for lipids and drugs. This matrix-free technique simplifies sample prep and prevents analyte redistribution for accurate spatial distribution imaging.
Area of Science:
- Analytical Chemistry
- Biochemistry
- Mass Spectrometry
Background:
- Desorption electrospray ionization (DESI) is a key ambient ionization technique.
- DESI facilitates direct analysis of samples without extensive preparation.
- It is particularly useful for analyzing biological tissues.
Purpose of the Study:
- To highlight the capabilities of DESI for analyzing biological tissue sections.
- To detail the process of obtaining spatial distribution images of molecules.
- To emphasize the advantages of DESI over traditional methods.
Main Methods:
- Direct analysis of microtome tissue slices under ambient conditions.
- Matrix-free ionization process.
- Continuous sample movement relative to sprayer and mass spectrometer inlet.
Main Results:
- DESI successfully identifies and maps spatial distributions of lipids and drug molecules.
- The technique avoids analyte redistribution by eliminating matrix deposition.
- Image acquisition at 250 microm resolution takes 30 min to 2 h.
Conclusions:
- DESI offers a simplified, direct, and effective method for analyzing biological tissues.
- The matrix-free approach preserves analyte integrity and spatial information.
- DESI is valuable for molecular imaging in fields like drug discovery and pathology.
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