Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
Rapid Commun Mass Spectrom. 2014 Mar 15;28(5):403-12. doi: 10.1002/rcm.6796.

Improved spatial resolution of matrix-assisted laser desorption/ionization imaging of lipids in the brain by alkylated derivatives of 2,5-dihydroxybenzoic acid.

Author information

  • 1Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, PA, 15219, USA; Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, PA, 15219, USA.

Abstract

RATIONALE:

Matrix-assisted laser desorption/ionization (MALDI) is one of the major techniques for mass spectrometry imaging (MSI) of biological systems along with secondary-ion mass spectrometry (SIMS) and desorption electrospray mass spectrometry (DESI). The inherent variability of MALDI-MSI signals within intact tissues is related to the heterogeneity of both the sample surface and the matrix crystallization. To circumvent some of these limitations of MALDI-MSI, we have developed improved matrices for lipid analysis based on structural modification of the commonly used matrix 2,5-dihydroxybenzoic acid (DHB).

METHODS:

We have synthesized DHB containing -C6H13 and -C12H25 alkyl chains and applied these matrices to rat brain using a capillary sprayer. We utilized a Bruker Ultraflex II MALDI-TOF/TOF mass spectrometer to analyze lipid extracts and tissue sections, and examined these sections with polarized light microscopy and differential interference contrast microscopy.

RESULTS:

O-alkylation of DHB yields matrices, which, when applied to brain sections, follow a trend of phase transition from crystals to an oily layer in the sequence DHB → DHB-C6H13 → DHB-C12H25 . MALDI-MSI images acquired with DHB-C12H25 exhibited a considerably higher density of lipids than DHB.

CONCLUSIONS:

Comparative experiments with DHB and DHB-C12H25 are presented, which indicate that the latter matrix affords higher lateral resolution than the former.

Copyright © 2014 John Wiley & Sons, Ltd.

PMID:
24497278
[PubMed - in process]
PMCID:
PMC3973445
[Available on 2015/3/15]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Icon for John Wiley & Sons, Inc.
    Loading ...
    Write to the Help Desk