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Yamil Simon (Fed)

Dr. Yamil Simon is currently a Research Chemist at the National Institute of Standards and Technology.

He received his Ph.D. at the Pontifical Catholic University of Chile and a Postdoctoral Fellowship at Northwestern University, Evanston, Illinois.  

His research interests include theoretical and experimental studies of molecular reactivity, fragmentation of small molecules under collision induced dissociation conditions, development and validation of MS spectral libraries, and analytical and bioinformatics tools for metabolomics. He has published numerous research papers, book chapters and been a contributor in the development of the NIST MS/MS library.


Main Ongoing Projects


  • Characterization of Biological Standard Reference Materials: We develop standards, spectral libraries, data analysis tools and methods for the profiling of complex biological materials. Our purpose is to find reproducible procedures to identify as many compounds as possible in biological samples using LC-MS/MS. The study of the reliability and reproducibility of the electrospray measurements of complex biological materials is central to all our work. Multivariate statistical techniques are extensively used for these purposes. 
  • Material-oriented Tandem Mass Spectral Libraries: NIST has long developed and provided reference materials to assist others in making reliable measurements. Also,  NIST is responsible for an evaluated, tandem mass spectral library as an extension of the NIST/EPA/NIH Mass Spectral Library and the NIST Peptide Mass Spectral Library. In an effort to further characterize organic materials that are amenable to mass spectrometric analysis, we are developing methods to represent chemical constituents, both identified and unidentified, in a mass spectral library. Our objective is to develop tandem mas spectral libraries that include spectra of all species that can be detected by MS and are present in complex biological standard reference materials. Among other applications, these libraries can help to lower the false discovery rates in metabolomics and to find metabolic pathways of 'unknown' components. 
  • Study of the Fragmentation of Small Molecules under Collision Induced Dissociation Conditions: In the course of expanding the NIST library of MS/MS spectra for use in metabolomics, we recorded the spectra of many chemical compounds using electrospray ionization in conjunction with several types of mass spectrometers. The quality control process to incorporate these spectra to the library often involves comparison of spectra from different mass spectrometers and assignment of each peak in the spectrum to a reasonable fragment ion. Frequently, to make sense of the spectrum, a more detailed study of the fragmentation process is needed. In addition to the experimental work, theoretical investigations are carried out to confirm the validity of the fragmentation models. 
NRC Postdoctoral Research Opportunity



Metabolomics Test Materials for Quality Control: A Study of a Urine Materials Suite

Dan Bearden, David A. Sheen, Yamil Simon, Bruce A. Benner Jr., Werickson Fortunato de Carvalho Rocha, Niksa Blonder, Katrice A. Lippa, Richard Beger, Laura Schnackenberg, Jinchun Sun, Khyati Mehta, Amrita Cheema, Haiwei Gu, Ramesh Marupaka, Nagana Gowda, Daniel Raftery
There is a lack of experimental reference materials and standards for metabolomics measurements, such as urine, plasma, and other human fluid samples. Reasons
Created October 9, 2019, Updated December 8, 2022