Analysis of Tyrosine and its Halogenated Forms and Tripeptide –Metal Ion Clusters Using Mass Spectrometry
Master of Science
Joong-Won Shin, Ph.D.
Walter Henne, Jr., Ph.D.
Kulugammana Ranmohotti, Ph.D.
The aim of this research project was to measure the differences in proton affinities of tyrosine and its halogenated forms, 3-chlorotyrosine and 3-iodotyrosine. Tandem mass spectrometry was used here to measure the proton affinities. These amino acids were formed as protonated dimers with amino acids of known proton affinity and were introduced into the instrument through electrospray ionization (ESI). Based on the intensities of the protonated amino acids appeared in the mass spectrum when the dimer was isolated and fragmented, the proton affinities of the sample amino acids were calculated.
The research project was on mass spectrometry of mixtures of peptides and metals. A tripeptide was mixed with different metals of certain concentration and were introduced into the instrument through electrospray ionization (ESI) using a syringe pump. Later, the [metal+peptide-H]+ of the tripeptide and the metal ion was isolated and fragmented. This shows how the tripeptide fragments specific to each of the doubly charged metal ion.
Gannamani, Bharathi, "Analysis of Tyrosine and its Halogenated Forms and Tripeptide –Metal Ion Clusters Using Mass Spectrometry" (2014). All Capstone Projects. 87.