The Mass Spectrometry Facility

The mass spectrometry facility currently has two mass spectrometers, a Voyager DE-STR (Applied Biosystems) and a QStar/Pulsar (Applied Biosystems/MDS Sciex). The Voyager DE-STR is a MALDI-TOF (matrix assisted laser desorption ionization with a time of flight analyzer) workstation with delay extraction technology. It has a mass range of up to 500,000 Da for singly charged ions. The QStar/Pulsar is an electrospray ionization mass spectrometer also with a TOF analyzer and can detect masses up to 12000 Da for singly charged ions. Both instruments have high sensitivity (low fmol for peptides) and high resolution (10-50 ppm). In addition, the QStar/Pulsar can perform percursor ion scanning and enhanced pulsing to boost low signals. These features make this instrument well suited for identifying post-translational modifications such as phosphorylation. The facility also is equipped with an Ultimate HPLC system (LC Packings/Dionex) including a zero dead volume solvent switching system and a Famos autosampler. This HPLC system is designed for nanoflow applications (high sensitivity) and is interfaced with the QStar/Pulsar for on-line fragmentation, sequencing and identification of peptides. The facility is capable of analyzing by mass spectrometry proteins, peptides, oligonucleotides, lipids, carbohydrates and small molecules.
Please call (410-614-6968) or email (rcole@jhmi.edu) the director your questions on the application of mass spectrometry to your research objectives.