Mass Spectrometry Service

Mass Spectrometry Service

The Chemical Analysis Facility currently has 3 instruments, consisting of an LC-MS system and two GC-MS systems. A more detailed description of the instrument capabilities are given below:

Shimadzu LCMS-2010EV – Quadrupole Mass Spectrometer

Key System Components:

  • Binary Gradient HPLC capability
  • Electrospray Ionization (ESI)
  • Atmospheric Pressure Chemical Ionization (APcI)
  • Photo Diode Array Detector
  • 2000 amu quadrupole mass analyser

HPLC Capabilities

  • Acceptable solvents: water, methanol, acetonitrile, most reversed phase solvents,
  • Acceptable modifiers: DMF (10%), TFA, acetic acid, formic acid (all <1%), ammonium hydroxide, tetrabutylammonium hydroxide, HFBA (all < 1mM).
  • Unacceptable solvents: benzene, toluene, pentane, hexane, carbon tetrachloride, carbon disulfide.
  • 2.1 mm and smaller columns preferred.
  • All chromatographic procedures developed should be free of non-volatile buffers,
    surfactants, salts and non-volatile ion pair reagents.

Electrospray Ionization (ESI)

  • Means of delivering nonvolatile analytes into the gas phase for mass analysis.
  • Has the ability to place multiple charges on a single molecule. The multiply charged species are detected by their mass-to-charge ratio.
  • Supports flow rates between 0.001-1.0 mL/min
  • Best used on molecules which are charged in solution or readily accept a charge. Particularly well suited to the analysis of biomolecules.
  • Allows for molecular weight determination of proteins and peptides with molecular weights up to 100 kDaltons; lipids, oligonucleotides and polysaccharides, up to 10 kDaltons.
  • The low mass limit is around 150 Daltons.
  • Provides low picomolar detection limits

Atmospheric Pressure Chemical Ionization (APCI)

  • Useful for small, polar thermally labile compounds.
  • Supports flow rates between 0.05-2.0 mL/min. The molecular weights of the compounds analysed are generally less than 2000 Daltons.

Photo Diode Array Detector (PDA)

  • Allows the simultaneous collection of UV/Vis spectrum and ESI/APcI Mass Spectrum of your compounds, thereby providing additional data to complement your MS data

Quadrupole Mass Analyser

  • Has a mass range for singly charged ions of 10-2000 Daltons with unit resolution across the entire mass range.
  • Has a maximum scan speed 6000 amu/sec (centroid) or 4000 amu/sec (profile).
  • Can detect both positive and negative ions.
  • Can perform a variety of MS experiments that are helpful in determining
    the structure of the molecule—
Back to the top of this page