The winner of the Award for Outstanding Achievement in Mass Spectrometry was Richard Caprioli of Vanderbilt University. First reported in Nature Medicine in 2001, Professor Caprioli has been developing and applying a technique called MALDI MS Imaging. This is a fascinating technique where a tissue slice is placed directly on a sample plate, prepped with a MALDI matrix, pixilated into discrete spots, and analyzed by MALDI–TOF. The proteins present in each spot can be identified and mapped back to the location in the tissue from where it came. This results in the construction of a protein map of the tissue where different colors can be assigned to various proteins of interest and intensities reflect protein concentrations.
What’s really intriguing about this technique is the potential for a paradigm shift in the way that clinical pathologists and histologists do their jobs. For example, a histologist traditionally would use a stain to define a tumor margin in a biopsy, but the molecular profile revealed by the MALDI MS image can expose oncogenic proteins found out-of-bounds of the tumor. This can help guide surgeons in the removal of all cancerous tissue, reducing the chance of relapse.
Apparently, when Professor Caprioli first told colleagues about his idea of sticking tissue slices into a mass spectrometer, they all thought he was a little nuts. His work is a fine example of how what first seems like a zany idea in analytical chemistry can turn out to have a very practical application in the clinic!
Allison Doerr (Assistant Editor, Nature Methods)