Fourier Transform MS

[Emiedoo]

Hi All,
Please forgive me for the following questions but I really need some help.
Could someone give me insight into the advantages of using a Fourier Transform Mass Spectrometer in the area of proteomics and metabolomics i.e screening for proteins in serum and urine from humans and animals aswell as extracts from tissues and cells. I am not familiar with this technology.

Secondly if a laboratory wanted to purchase an MS system for the above applications aswell as the ability to screen for small molecule metabolites what type of system would you recommend that will cover the widest number of applications in these areas. What are the advantages of this type of technique over FTMS.

Really grateful for your responses,
Thank you

[AM_france]

Hi Emiedoo,

here are the advantages of FTMS : high resolution (routinely 100 000 until 1 000 000) , high mass measure precision (1 to 10 ppm); high sensitivity (amol) , high dynamic range ; drawback : price.....
in proteomics science, FTMS instruments (LTQ-FT or LTQ orbitrap for example) are considered as rolls royce

[Emiedoo]

Hello AM France, Many thanks for your reply
Thank you for letting me know some of the advantages

"in proteomics science, FTMS instruments (LTQ-FT or LTQ orbitrap for example) are considered as rolls royce"

Please forgive me but what does LTQ and LTQ orbitrap stand for and how briefly are they different??


Also I am new to this but if a laboratory was to choose one of these types of instrument for proteomics/metabolomics work which one or what other less expensive instruments are there that could be considered...

Sorry for all the basic questions but I am a newbie.....Any help would be appreciated

Thanks,
Emiedoo

[leadazide]

LTQ is a linier ion trap from thermo fisher scientific.. The Orbitrap is a "new" type of detector which is added to the LTQ. Please search for Orbitrap on thermo.com for more information. I know the orbitrap is rutinly used for proteonomics in quite a few places.. and the price is more reasonable then a FT-MS

[Kostas Petritis]

With the introduction of Orbitraps I would say that the only advantage of the FTICR is only if you do intact protein analysis where you need very high mass resolutions. In addition to the higher price though, FTICR require liquid nitrogen/Helium making their maintenance more problematic and costly. Finally, FTICR have lower cycle times; if you want high mass accuracy MS/MS it is problematic, and there are mass biases. Again, unless you do intact protein analysis (and in this case you would probably want more than 7T magnet that is currently available from Thermo) it is not worthy to invest to one.

For proteomic/metabolomic applications an Orbitrap or a fast Q-ToF should be the MS detectors of choice...

By the way here is the definition of Orbitrap:

"An ion trapping device that consists of an outer barrel-like electrode and a coaxial inner spindle-like electrode that form an electrostatic field with quadro-logarithmic potential distribution. The frequency of harmonic oscillations of the orbitally trapped ions along the axis of the electrostatic field is independent of the ion velocity and is inversely proportional to the square root of m/z so that the trap can be operated as a mass analyzer using image current detection and Fourier transformation of the time domain signal."

[Emiedoo]

Sorry for the delay in replying. Many thanks for your help with this query.