Scanning microprobe matrix-assisted laser desorption ionization (SMALDI) mass spectrometry: Instrumentation for sub-micrometer resolved LDI and MALDI surface analysis

  • Bernhard SpenglerEmail author
  • Martin Hubert


A new instrument and method is described for laterally resolved mass spectrometric surface analysis. Fields of application are in both the life sciences and the material sciences. The instrument provides for imaging of the distribution of selected sample components from natural and artificial surfaces. Samples are either analyzed by laser desorption ionization (LDI) time-of-flight mass spectrometry or, after preparation with a suitable matrix, by matrix-assisted laser desorption ionization (MALDI) mass spectrometry. Areas of 100 × 100 μm are scanned with minimal increments of 0.25 μm, and between 10,000 and 160,000 mass spectra are acquired per image within 3 to 50 min (scan rate up to 50 pixels per s). The effective lateral resolution is in the range of 0.6 to 1.5 μm depending on sample properties, preparation methods and laser wavelength. Optical investigation of the same sample area by UV confocal scanning laser microscopy was found to be very attractive in combination with scanning MALDI mass analysis because pixel-identical images can be created with both techniques providing for a strong increase in analytical information. This article describes the method and instrumentation, including first applicational examples in elemental analysis, imaging of pine tree roots, and investigation of MALDI sample morphology in biomolecular analysis.


Scanning Near Field Optical Microscopy Focus Diameter Laser Microprobe Laser Desorption Mass Spectrometry Laser Microprobe Mass Spectrometry 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© American Society for Mass Spectrometry 2002

Authors and Affiliations

  1. 1.Institute of Inorganic and Analytical ChemistryJustus-Liebig University GiessenGiessenGermany

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