Exact Mass Measurement

Exact Mass Measurement utilizes the mass accuracy of a mass spectrometer to assign (unambiguously) the elemental composition to an unknow m/s. Depending on the accuracy of the MS and the mass range which was acquired, given certain constraints (i.e. allow only certain elements) a unique elemental composition can be assigned.

With its unsurpassed mass accuracy, hybrid FT instruments are very well suited to analyze the samples in question. Samples can of course be of any nature varying form small organic molecules to intact proteins. For selected applications MS/MS spectra of small molecules can be acquired.

The samples can be analysed by the following platforms:

• ESI-FTMS: Either the LTQ-FT or LTQ-Orbitrap. Samples are typically directly infused, but also EMM can be performed from online LC-MS samples.

Support Modes

All technologies are available in both the User lab mode and FGCZ Analytical Service.

Contacts

Endre Laczko - user lab
Rene Brunisholz - Service ETH
Peter Hunziker - Service UZH

Selected publication

Reinhardt A, Emmenegger C, Gerrits B, Panse C, Dommen J, Baltensperger U, Zenobi R, Kalberer M.
Ultrahigh Mass Resolution and Accurate Mass Measurements as a Tool To Characterize Oligomers in Secondary Organic Aerosols.
Analytical Chemistry 2007

Abbreviations

MS - Mass Spectrometry
MS/MS - Tandem Mass Soectrometry
FTMS - Fourier Transformation Mass Spectrometry
ESI - Electrospray Ionisation
LC - Liquid Chromatography