A one-step matrix application method for MALDI mass spectrometry imaging of bacterial colony biofilms.
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. Copyright © 2016 John Wiley & Sons, Ltd.
['Li|Bin|B|', 'Comi|Troy J|TJ|', 'Si|Tong|T|', 'Dunham|Sage J B|SJ|', 'Sweedler|Jonathan V|JV|']
D000362:Agar D001412:Bacillus subtilis D001431:Bacteriological Techniques D018441:Biofilms D005841:Gentisates D061848:Optical Imaging D012996:Solutions D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
matrix application biofilms airbrush automatic sprayer MALDI MSI