Silent Matrix For MALDI Mass Spec

Proteomics researchers rely heavily on a technique called matrix-assisted laser desorption/ionization (MALDI) mass spectrometry to analyze proteins, but this workhorse method is no stallion for scientists curious about small metabolites in their sample, such as the fatty acids. This is because data from small metabolites get lost in a "haystack" of signals that come from laser ionization of the solid matrix formed by cocrystallizing small amounts of the sample with support material. So a team led by Aleš Svatoš of the Max Planck Institute for Chemical Ecology, in Jena, Germany, decided to "remove the haystack." Using Brønsted-Lowry acid-base theory, the team developed a dimethylaminonaphthalene matrix that doesn't produce ions when irradiated and thus does not add experimental noise to the data (Proc. Natl. Acad. Sci. USA, DOI: 10.1073/pnas.0900914106). Proof of principle for the new matrix was demonstrated by looking at the metabolites produced when a leaf is cut and the metabolites produced by male and female flies. When using the new approach with existing MALDI instruments, researchers "should be able to perform high-throughput metabolomics 10 times faster than before," Svatoš notes.