We know that you are asking yourself what these three words from the title have in common: Proteomics, Mass Spectrometry and Puerto Rico. However, if we analyze them closely you will figure out. Beginning with proteomics, the word in Spanish is a bit difficult to pronounce: proteomica. Proteomics is the science field that studies proteins and their structure and function. And what does "Mass Spectrometry" have to do in this? WellÖ a lot because mass spectrometry (MS) is one of the analysis techniques used to determine the mass, identity and modification of proteins. And for those that are wondering what is Puerto Rico's role in all this; please blame Dr. Irving E.