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Direct Analysis of Triacylglycerols from Crude Lipid Mixtures by Gold Nanoparticle-Assisted Laser Desorption/Ionization Mass Spectrometry

  • Jeongjin Son
  • Gwangbin Lee
  • Sangwon ChaEmail author
Application Note

Abstract

Triacylglycerols (TAGs), essential energy storage lipids, are easily detected by conventional MALDI MS when occurring on their own. However, their signals are easily overwhelmed by other lipids, mainly phosphatidylcholines (PCs) and, therefore, require purification. In order to profile TAGs from crude lipid mixtures without prefractionation, we investigated alternative matrixes that can suppress phospholipid ion signals and enhance cationization of TAGs. We found that an aqueous solution of citrate-capped gold nanoparticles (AuNPs) with a diameter of 12 nm is a superior matrix for the laser desorption/ionization mass spectrometry (LDI MS) of TAGs in crude lipid mixtures. The AuNP matrix effectively suppressed other lipid signals such as phospholipids and also provided 100 times lower detection limit for TAGs than 2,5-dihydroxybenzoic acid (DHB), the best conventional MALDI matrix for TAGs. The AuNP-assisted LDI MS enabled us to obtain detailed TAG profiles including minor species directly from crude beef lipid extracts without phospholipid interference. In addition, we could detect TAGs at a trace level from a total brain lipid extract.

Key words

Laser desorption/ionization Triacylglycerol Phophatidylcholine Gold nanoparticle Graphene oxide 

Notes

Acknowledgments

The authors acknowledge support for this research by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT, and Future Planning (NRF-2013R1A1A1010947).

Supplementary material

13361_2014_844_MOESM1_ESM.docx (1.2 mb)
ESM 1 (DOCX 1269 kb)

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Copyright information

© American Society for Mass Spectrometry 2014

Authors and Affiliations

  1. 1.Department of ChemistryHankuk University of Foreign StudiesYonginKorea

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