The Center for Mass Spectrometry consists of four instruments, giving researchers access to a variety of modern mass spectral techniques. An Esquire-LC (Bruker) electrospray ion trap mass spectrometer is used primarily for biopolymer work (polypeptides, proteins, polysaccharides, etc.). Multiple stage tandem capabilities make it perfectly suited for peptide sequencing and structure verification. A REFLEX III (Bruker) MALDI/TOF mass spectrometer is used primarily for characterization of synthetic and biological polymers in a very broad mass range (up to 500,000 Da). A JMS-700 MStation (JEOL) two-sector mass spectrometer has a variety of ionization sources for small molecules (electron impact/chemical ionization, fast atom bombardment, electrospray and field desorption/ionization) and provides high resolution high mass accuracy measurements. It is interfaced with a GC unit and has tandem capabilities. An HP 5989A (Hewlett Packard) GC/MS system (quadrupole mass analyzer) is used for analyses of low molecular weight compounds. (B162 Conte, 577-1528, www.pse.umass.edu/ms/)