MS - m or Mr or m/z or what?

Ken Mitchelhill (k.mitchelhill@medicine.unimelb.edu.au)
Fri, 19 Jun 1998 11:48:35 +1000

Colleagues,

I am trying to put a "style page" together for the Journal of Biomolecular
Techniques and am scratching my head a bit about how to represent mass.

The Journal of Biological Chemistry allows the use of two mass terms, "m"
and "Mr" where:

"Molecular mass (symbol m) is expressed in daltons (Da); one dalton is 1/12
of the mass of carbon 12. Molecular weight (Mr, relative molecular mass) is
the ratio of the mass of a molecule to 1/12 of the mass of carbon 12 and is
dimensionless. Hence, it is not correct to express Mr in daltons."

There is no mention of the term "m/z" although I am used to seeing this in
a whole host of mass spectrometric output.

I was curious as to what the feeling out there was with regard to the
"correct" way to express mass in the context of our experiments?

Ken

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Ken I. Mitchelhill
The John Holt Protein Structure Laboratory
St. Vincent's Institute of Medical Research
41 Victoria Parade
Fitzroy 3065 Victoria
AUSTRALIA

Telephone: 61-3-9288 2480
Facsimile: 61-3-9416 2676

Email: k.mitchelhill@medicine.unimelb.edu.au

Laboratory: http://www.medstv.unimelb.edu.au/WWWDOCS/SVIMRdocs/JHPSL.html
ABRF: http://www.abrf.org

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