A one-step matrix application method for MALDI mass spectrometry imaging of bacterial colony biofilms

Bin Li, Troy J. Comi, Tong Si, Sage J.B. Dunham, Jonathan V. Sweedler

Research output: Contribution to journalArticle


Matrix-assisted laser desorption/ionization imaging of biofilms cultured on agar plates is challenging because of problems related to matrix deposition onto agar. We describe a one-step, spray-based application of a 2,5-dihydroxybenzoic acid solution for direct matrix-assisted laser desorption/ionization imaging of hydrated Bacillus subtilis biofilms on agar. Using both an optimized airbrush and a home-built automatic sprayer, region-specific distributions of signaling metabolites and cannibalistic factors were visualized from B. subtilis cells cultivated on biofilm-promoting medium. The approach provides a homogeneous, relatively dry coating on hydrated samples, improving spot to spot signal repeatability compared with sieved matrix application, and is easily adapted for imaging a range of agar-based biofilms.

Original languageEnglish (US)
Pages (from-to)1030-1035
Number of pages6
JournalJournal of Mass Spectrometry
Issue number11
StatePublished - Nov 1 2016



  • airbrush
  • automatic sprayer
  • biofilms
  • matrix application

ASJC Scopus subject areas

  • Spectroscopy

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