Matrix‐assisted laser desorption/ionization imaging mass spectrometry of pollen grains and their mixtures

Abstract

The fast and univocal identification of different species in mixtures of pollen grains is still a challenge. Apart from microscopic evaluation and Raman spectroscopy, no other techniques are available. Matrix-assisted laser desorption/ionization (MALDI) imaging mass spectrometry was applied to the analysis of extracts of single pollen grains and pollen mixtures. Pollen grains were fixed, treated and covered with matrix directly on the MALDI target. Clearly resolved MALDI ion intensity images could be obtained enabling the identification of single pollen grains in a mixture. Our results demonstrate the potential and the suitability of MALDI imaging mass spectrometry as an additional method for the identification of pollen mixtures.