Services | Mass Spectrometry Facility | SIU

Southern Illinois University



Mass Spectrometry Facility


Sample Analysis by Facility Personnel

Facility personnel routinely analyze submitted samples (see services listed below). Guidelines and forms for sample submission are found under "Protocols" and "Sample Submission".  Please note that the Facility is not equipped or licensed to handle radioactive and biohazardous samples.

  1. IRMS: Stable isotopes δ13C, δ15N, δ2H and δ18O for both solids and liquids.
  2. GC-MS: Mass spectrometric analysis of mixtures of volatile compounds.
  3. MALDI - TOFMS: Generation of peptide mass fingerprints followed by public database searching or  intact protein molecular weight determination.
  4. MALDI - TOF/TOFMS: The use of collision induced dissociation (CID) to fragment and sequence peptide ions. The MS/MS spectral data can then be searched against public databases for protein identification.
  5. Direct infusion Electrospray MS: Syringe pump used to infuse solution of pure sample for mass spectrometric analysis.  Note: Not appropriate for complex mixtures.
  6. HPLC- Electrospray MS or MS/MS: HPLC separation combined with mass spectrometric (MS) analysis or the use of collision induced dissociation (CID) in various types of MS/MS experiments to detect product ions, to scan for parent ions that form a specific product ion, or to screen for the loss of neutral fragments.

Use of Instruments by Trained Investigators

Instruction on the use of Facility instruments is available. Training involves lecture and hands-on experience with the instruments (usually 2.5 - 8 hours). After approval by the instructor (Application for Training (PDF format)), the investigator is expected to operate the instruments with minimal guidance from Facility personnel.  Refer to "Rates" for the cost of training.

The Facility offers training on gas chromatography - mass spectrometry (GC-MS) and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI TOFMS).  GC-MS allows for the separation and subsequent detection of volatile, small molecular weight compounds (< 800 Da) with the production of electron impact (EI) mass spectra.  MALDI TOFMS is routinely used for the analysis of peptides and proteins.  Peptide analysis is performed on the ABI 4700 Proteomics Analyzer and intact protein analysis is performed on the Bruker Daltonics Microflex.  Both positive and negative ions can be detected on either instrument. These features provide the necessary flexibility to optimize each analytical method for individual samples.