para-Nitroaniline is a Promising Matrix for MALDI-MS Imaging on Intermediate Pressure MS Systems

  • Rory T. Steven
  • Alan M. Race
  • Josephine Bunch
Application Note


para-Nitroaniline (PNA) is presented as a promising matrix for matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI) on an intermediate-pressure ion source (~1 Torr) QqTOF instrument using an Nd:YVO4 laser operated at 5 kHz. An imaging study was carried out to determine the utility of PNA at this pressure by analyzing 14 tissue sections. We demonstrate acquisition of high-quality imaging data over a 6-h period in the ion source. In this study, comparisons were made between PNA and α-cyano-4-hydroxycinnamic acid (CHCA) in positive ion mode to demonstrate the utility of PNA in these circumstances. PNA performed as well as or better than CHCA in terms of lipid ion intensities, resulting in lower levels of ion fragmentation and in lower incidences of analyte migration at the edges of the tissue sections when using airspray matrix deposition.

Key words

para-Nitroaniline MALDI-MSI Mass spectrometry imaging Intermediate pressure MALDI 



The authors thank the EPSRC for funding via studentships for R.T.S. and A.M.R. through the PSIBS Doctoral Training Centre at the University of Birmingham (EP/F50053X/1).

Supplementary material

13361_2013_586_MOESM1_ESM.docx (9.3 mb)
ESM 1 (DOCX 9512 kb)


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Copyright information

© American Society for Mass Spectrometry 2013

Authors and Affiliations

  • Rory T. Steven
    • 1
    • 2
  • Alan M. Race
    • 1
    • 2
  • Josephine Bunch
    • 1
    • 2
  1. 1.PSIBS CentreUniversity of BirminghamBirminghamUK
  2. 2.School of ChemistryUniversity of BirminghamBirminghamUK

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