HYBRID (EBQQ) MASS SPECTROMETER

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This request is for a Hybrid Mass Spectrometer to be part of the Mass Spectrometry Laboratory at the University of Kansas, serving the Departments of Chemistry, Medicinal Chemistry, Pharmaceutical Chemistry, Pharmacology and Toxicology, KU Medical Center and the centers for Biomedical and Bioanalytical Research. The primary need is for increased fast atom bombardment (FAB) capability. This has been an established service lab with growing capability and sample load for 10 years. A total of thirty groups currently use the lab and at 7/12 through the fiscal year the lab has run 1690 samples and will easily reach 2500 by July. This work is being carried out on three facility instruments,a Varian-NUT CH5, a Nermag quadrupole GC/MS system, and a high resolution VG ZAB HS. The Nermag and the ZAB are used for the bulk of the samples. The CH5 (bought in 1970) is obsolete as a FAB instrument. The Nermag is currently saturated in use by probe and GC experiments. The ZAB has reached near saturation with routine exact mass and FAB analysis. Starting in July of 1989 the demand for FAB analysis has increased 6 times from the previous year. FAB work is expected to double again as peptide molecular weight experiments are done in support of four groups just beginning to use mass spectrometry for peptide characterization. The peptide projects involve the identification and localization of modified amino acids in small peptides. The MS/MS capability of the hybrid will be used to provide the sequence information not available in the FAB experiments. The unit mass precursor and fragment ion resolution obtainable with a hybrid in CAD experiments will be vital for peptide projects involving bromine and deuterium labeled peptides. Two groups are currently synthesizing coordination compounds and have been the major FAB users for confirmation of intermediates and final products. Both groups have had mixed success in obtaining molecular ions from their metal containing samples. Frequently demetallated species are observed in the FAB spectra. Similar compounds have been characterized by Field Desroption (FD). The use of FD for coordination compounds provides a soft ionization method that avoids the complications of matrix chemistry.