Mass spectrometry imaging of triglycerides in biological tissues by laser desorption ionization from silicon nanopost arrays

Abstract

Mass spectrometry imaging (MSI) is used increasingly to simultaneously detect a broad range of biomolecules while mapping their spatial distributions within biological tissue sections. Matrix-assisted laser desorption ionization (MALDI) is recognized as the method-of-choice for MSI applications due in part to its broad molecular coverage. In spite of the remarkable advantages offered by MALDI, imaging of neutral lipids, such as triglycerides (TGs), from tissue has remained a significant challenge due to ion suppression of TGs by phospholipids, e.g.

Mass Spectrometry Imaging of Bio‐oligomer Polydispersity in Plant Tissues by Laser Desorption Ionization from Silicon Nanopost Arrays

“…In conclusion, the complementarity between NAPA -LDI-MSI and MALDI-MSI in chemical imaging of oligomers from three different biopolymers,PHB,PGA, and polysaccharides in infected plant tissue sections was demonstrated. NAPA -LDI-MSI was shown to provide higher ionization efficiency and wider repeat unit range coverage for oligomers of PHB and polysaccharides from the tissue compared to MALDI-MSI, whereas oligomers of PGA were only imaged by the latter.Complementary application of NAPA -LDI and MAL-DI for MSI of biological homopolymers provides new insight into the storage of energy and molecular feedstock by various organisms.A sN APA-LDI has been demonstrated to exhibit advantages in detecting and imaging compounds that are suppressed in MALDI, e.g.,P HB and neutral lipids, [38,39] the complementarity of the two platforms in MSI put forth promising applications in the biomedical and clinical areas.…”

“…Complementary application of NAPA‐LDI and MALDI for MSI of biological homopolymers provides new insight into the storage of energy and molecular feedstock by various organisms. As NAPA‐LDI has been demonstrated to exhibit advantages in detecting and imaging compounds that are suppressed in MALDI, e.g., PHB and neutral lipids, [38, 39] the complementarity of the two platforms in MSI put forth promising applications in the biomedical and clinical areas.…”

“…[34,37,38] Particular advantages of NAPA -LDI-MSI were recently demonstrated by comparing it to MALDI-MSI with respect to the ionization efficiencya nd spatial mapping of certain lipid classes in biological tissue sections. [38,39] NAPA -LDI-MSI was shown to enhance the ionization for particular lipid classes that are often difficult to detect using traditional organic MALDI matrices,e specially in the presence of phosphatidylcholines (PCs), such as phosphatidylethanolamines (PEs) and triglycerides (TGs). [38,39] These results demonstrated the complementarity of lipid coverage between NAPA -LDI-and MALDI-MSI and gave rise to their combined application for multimodal imaging.…”

“…[38,39] NAPA -LDI-MSI was shown to enhance the ionization for particular lipid classes that are often difficult to detect using traditional organic MALDI matrices,e specially in the presence of phosphatidylcholines (PCs), such as phosphatidylethanolamines (PEs) and triglycerides (TGs). [38,39] These results demonstrated the complementarity of lipid coverage between NAPA -LDI-and MALDI-MSI and gave rise to their combined application for multimodal imaging. [40] Here,w es how the detection and molecular imaging of oligomers of PHB,p olyglutamic acid (PGA), and polysaccharides in soybean root nodule tissue sections using NAPA -LDI-MSI and MALDI-MSI.…”

Applications of ambient ionization mass spectrometry in 2020: An annual review

“…Given the obvious importance of this class of metabolites, the development of analytical techniques for the fast and reliable analysis of such molecules has important implications in disease diagnostics. Although lipids are of great interest, the analysis of lipids such as TGs can be challenging due to ion suppression effects primarily caused by the presence of PCs 39 . Unsihuay et al took a nano‐DESI approach to the imaging of TGs in murine tissues, with an aim to establish the optimum conditions for TG detection whilst also reducing problems of ion suppression 40 .…”